Cat Scratch Disease and Other Bartonella Importance
Transcription
Cat Scratch Disease and Other Bartonella Importance
Cat Scratch Disease and Other Zoonotic Bartonella Infections Bartonellosis, Cat Scratch Fever, Benign Inoculation Lymphoreticulosis, Benign Inoculation Reticulosis, Regional Granulomatous Lymphadenitis, Parinaud Oculoglandular Syndrome, Bacillary Angiomatosis Last Updated: July 2012 Importance Members of the genus Bartonella are maintained in many domesticated and wild animal hosts. Bartonella henselae, the best understood species, infects housecats and other members of the Felidae. Additional species of Bartonella are found in cats, dogs, cattle, rodents, rabbits, bats or other wild and domesticated animals. While the vast majority of these infections are asymptomatic, Bartonella spp. have been implicated occasionally in illnesses in animals. However, proving a causative role is difficult, and at present, their significance as pathogens for animals is unclear. B. henselae is, however, a zoonotic pathogen. In immunocompetent people, this organism usually causes cat scratch disease, a benign, self-limiting illness characterized by fever and regional lymphadenopathy. Occasionally, cat scratch disease may progress to complications such as neuroretinitis, neurological signs, osteomyelitis and other conditions. The complications usually resolve without sequelae in healthy people, although they can be life-threatening in rare cases. Endocarditis is usually the most serious concern. In contrast, B. henselae infections are often severe in immunocompromised individuals, and can be fatal without antibiotic treatment. Other species of Bartonella have also been linked occasionally to human illnesses, with varying levels of evidence for a causative role. Etiology Bartonella spp. are fastidious, pleomorphic, Gram negative rods (bacilli) in the family Bartonellaceae. Some of these organisms were previously classified in the genera Rochalimaea and Grahamella. The Bartonellaceae formerly belonged to the order Rickettsiales, but are now in the α-2 subgroup of the Proteobacteria. More than 20 species of Bartonella have been described in animals, and a number of these organisms are thought to be zoonotic or potentially zoonotic. Among them, only B. henselae is well understood. Two species, B. quintana and B. bacilliformis, are maintained in human populations, and cause illness in people. All Bartonella species are closely related and may cross-react in some serologic assays. Some species, such as B. clarridgeiae and B. rochalimae, are particularly close. Co-infection with more than one species of Bartonella is possible. B. henselae, B. quintana and B. bacilliformis have been established as the causative agents for well-defined syndromes in people. Other species have also been implicated rarely in clinical cases in people or animals. However, proving that a Bartonella infection is the cause of an illness, rather than an incidental finding, can be difficult. In animals, criteria proposed for possible Bartonella involvement include detection of the organism by culture, PCR assay or serology, together with the exclusion of other causes, and response to treatment with a drug that has activity against this organism. If the syndrome is associated with Bartonella infection in other species, this is also suggestive. However, diagnosis can still be challenging, and findings should be interpreted with caution. Bartonella spp. infect erythrocytes and vascular endothelial cells, and asymptomatic bacteremia can be very common, especially in the reservoir hosts. PCR does not prove that viable organisms are present, and contamination with Bartonella spp. in blood or flea dirt may result in false positive results. Serology is particularly problematic, as IgG antibodies to Bartonella can persist for some time after infection, and many healthy animals and humans are seropositive. Conversely, Bartonella spp. are fastidious and can be difficult to culture, antibodies are not always present in infected individuals, and the organism is not always detected by PCR. Bartonella henselae: Cat scratch disease, bacillary angiomatosis and peliosis hepatis Bartonella henselae (formerly Rochalimaea henselae) is thought to cause most cases of cat scratch disease in humans. This organism also causes bacillary angiomatosis and peliosis hepatis, mainly in immunocompromised individuals. It has been implicated in other conditions such as fever of unknown origin. There are two major genotypes of B. henselae: type I (Houston-1) and type II (BA-TF/Marseille). Strain variations exist within these genotypes. There is some evidence that genotypes or strains might vary in their zoonotic potential. © 2012 page 1 of 20 Cat Scratch Disease Cats and other felids are the reservoir hosts, and usually carry the organism asymptomatically. Most human infections are thought to be acquired from housecats. B. henselae can also infect other animal species, and rare cases of human illness have been reported after bites or scratches from dogs. Illnesses in cats and other animals have occasionally been attributed to B. henselae, but proof of a causative role can be elusive. Other Bartonella species maintained in animals Cats are thought to be the reservoir hosts for B. clarridgeiae. This organism has been implicated in rare cases of cat scratch disease in people. It was also detected in a dog with endocarditis, and another dog with hepatopathy. Cats may also be the reservoir hosts for B. koehlerae. This organism appears to be very difficult to isolate. It has been implicated in a few cases of endocarditis in humans and dogs, as well as in rare cases of cat scratch disease. B. vinsonii subsp. berkhoffii is common in dogs and wild canids including coyotes and foxes. Both dogs and coyotes have been suggested as possible reservoir hosts. Most canids appear to be infected asymptomatically, but various illnesses have been attributed to this organism in case reports. In addition, B. vinsonii subsp. berkhoffii has been implicated in a few clinical cases in other animal species and people. B. rochalimae has also been found in dogs and wild canids, including foxes and coyotes, as well as in raccoons and various rodents. This organism has been implicated in rare cases of febrile illness in humans and endocarditis in dogs. Cattle are the reservoir hosts for B. bovis (formerly B. weisii). Although this organism is common in apparently healthy cattle, some authors suggest that it might have a causative role in bovine endocarditis. It has been detected occasionally in other animals. B. chomelii has also been found in cattle. The candidate species B. melophagi infects sheep. It was co-isolated with B. henselae from the blood of one person with a febrile illness. It was also isolated from another individual with symptoms of fatigue and muscle weakness. Numerous Bartonella species have been detected in mice, rats, shrews, ground squirrels, chipmunks, gerbils, jerboas and other rodents. Species that appear to be maintained in rodents include B. vinsonii subsp. arupensis, B. vinsonii subsp vinsonii, B. birtlesii, B. doshiae, B. peromysci, B. phoceensis, B. rattimassiliensis, B. talpae, B. taylorii, B. tribocorum, B. grahamii, B. elizabethae, B. queenslandensis and B. washoensis, among others. Many rodent-associated Bartonella species were formerly classified in the genus Grahamella. Some organisms, including B. vinsonii subsp. arupensis, B. vinsonii subsp vinsonii, B. elizabethae, B. washoensis, B. grahamii, B. rattimassiliensis and B. tribocorum, have been detected in rare cases of endocarditis, ocular disease or other illnesses Last Updated: July 2012 © 2012 in people. B. washoensis was implicated in endocarditis in a dog. The candidate species B. tamiae was cultured from the blood of three patients enrolled in a prospective study to determine the etiology of febrile illnesses in Thailand. The organisms isolated from these patients caused illness in experimentally infected mice. The reservoir host for B. tamiae is not known, although rats have been proposed. B. alsatica infects rabbits. Evidence of infection with this organism was found in two people with endocarditis, as well as an elderly woman with regional lymphadenopathy. All three had close contact with domesticated or wild rabbits. B. capreoli and B. schoenbuchensis have been found in deer. B. capreoli has also been isolated from elk (Cervus elephas), and B. schoenbuchensis was found in a cow. Bartonella DNA from an apparently novel species was detected by PCR in North American river otters (Lontra canadensis). Bartonella species, which appear to be distinct from the organisms found in small mammals, have been detected in a number of bat species. Non-zoonotic organisms: Bartonella quintana and Bartonella bacilliformis Two species of Bartonella are maintained in human populations. B. bacilliformis, which is endemic in areas of South America, causes Oroya fever (Carrión disease) in people. This syndrome is characterized by fever and hemolytic anemia, and is often followed by the development of cutaneous angioproliferative lesions (verruga peruana/ Peruvian wart). B. bacilliformis is not known to affect animals. B. quintana (formerly Rochalimaea quintana) is maintained in human populations, but it has been detected in animals on rare occasions. Notably, DNA from this organism was found in two feral cats and in an asymptomatic woman who had been bitten by one of the cats. In people, B. quintana causes trench fever, a louseborne, self-limited, febrile illness characterized by relapsing fever, malaise, arthralgia and other systemic signs, and often by erythematous macules or papules. B. quintana has also been linked to cases of endocarditis, and it can cause bacillary angiomatosis and peliosis hepatis in immunocompromised individuals. It is not known to cause illness in animals. Geographic Distribution B. henselae occurs worldwide in cats. The prevalence of different genotypes varies with the geographic region. B. henselae type I (Houston-1) is more common than type II in Japan and the Philippines. This genotype is also more prevalent in the eastern U.S., where it represents approximately half of all isolates, than in the western states. B. henselae type II (Marseille) is more common than type I in the western U.S., western Europe (France, Germany, page 2 of 20 Cat Scratch Disease Italy, the Netherlands and the U.K.) and Australia. Within a geographic area, the predominant genotypes in human clinical cases may or may not match the dominant genotypes in cats. Based on serological surveys, Bartonella vinsonii subsp. berkhoffii also appears to be present worldwide. Transmission Bartonella spp. are transmitted between animals by arthropods. Fleas appear to be the vectors for a number of species, but some organisms are spread by other arthropods including sandflies, lice, keds and possibly ticks. Bartonella henselae B. henselae is transmitted between cats by cat fleas (Ctenocephalides felis), probably via flea feces rather than saliva. This organism is reported to survive for 3 days in flea feces, which might result in contamination of the environment. Cats can also be infected experimentally by intravenous or intramuscular injection of feline blood, suggesting that iatrogenic spread (including transmission through blood transfusions) might be possible. Transmission was not reported when cats were in contact, but fleas were absent, indicating that casual contact and the sharing of food or water dishes are not significant sources of exposure. In one experiment, B. henselae was not spread by sexual contact (bacteremic females and uninfected males) or vertically to kittens. B. henselae occasionally infects other animals, and DNA from this organism has been detected in oral swabs from dogs, as well as in dog fleas (Ctenocephalides canis) removed from dogs. Other species of Bartonella Fleas are thought to be important vectors for a number of Bartonella species, including many that are associated with rodents. Although vector competence has not been determined in most cases, the rodent flea Ctenophthalmus nobilis was shown to transmit B. grahamii and B. taylorii between voles in the laboratory. Organisms that have been detected in the cat flea, in addition to B. henselae, include B. clarridgeiae, B. koehlerae and B. quintana. Evidence for Bartonella spp. was also found in other fleas including Pulex irritans found on a pet monkey, Pulex sp. from humans (the latter contained organisms most closely related to B. rochalimae and B. vinsonii subsp. berkhoffii), and P. irritans from the carcasses of red foxes. Other arthropods are also proven or potential vectors for some Bartonella species. B. bacilliformis is transmitted between people by the sandfly Lutzomyia verrucarum. Other Lutzomyia sandflies or other arthropods might also be capable of transmitting this organism, as outbreaks have been reported in areas where Lu. verrucarum is not endemic. The human body louse (Pediculus humanus humanus) is the main vector for B. quintana, but species such as head lice (Pediculus humanus capitis) might also be Last Updated: July 2012 © 2012 able to transmit this organism. DNA from rodent-associated Bartonella spp. has been detected in several species of lice that parasitize these animals. B. henselae and B. schoenbuchensis were found in deer keds (Lipoptena mazamae and Lipoptena cervi), and these organisms are thought to be vectors for B. schoenbuchensis. Sheep keds (Melophagus ovinus) might be important in transmitting B. melophagi. B. bovis DNA was reported in horn flies (Haematobia sp.), and B. henselae DNA in a stable fly (Stomoxys sp.). Bartonella DNA has also been found in the fly Hippobosca equina, bat flies (Trichobius major), bat bugs (Cimex adjunctus) and various mites on rodents and bats, as well as in some arthropods that clearly have no relevance as vectors, such as honeybees (Apis mellifera). It should be noted that evidence of infection does not, by itself, prove that an arthropod is a vector for an organism. The relevance of ticks as vectors for Bartonella is controversial. The possibility of tick-borne transmission was suggested by circumstantial or anecdotal evidence, such as rare case reports of Bartonella infections diagnosed soon after a tick bite. Bartonella spp. including B. henselae, B. vinsonii subsp. berkhoffii, B. quintana, B. washoensis and B. capreoli have been detected in various tick species, mainly by PCR. A few studies found that antibodies to Bartonella were more common in animals or people frequently exposed to ticks, although concurrent exposure to fleas and other vectors could not be ruled out. Three laboratory studies also suggest that ticks might serve as vectors for Bartonella, although they do not prove they are epidemiologically important. In one study, Dermacentor andersoni was shown to transmit B. bacilliformis between monkeys in the laboratory, probably by mechanical transmission. Transstadial transmission of B. henselae was demonstrated in Ixodes ricinus, using an artificial feeding system, and cats inoculated with dissected salivary gland from these ticks became bacteremic. Recently, I. ricinus was shown to act as a biological vector, when it transmitted B. birtlesii (a species found in rodents) between mice in the laboratory. Transmission of zoonotic Bartonella to humans People mainly seem to acquire B. henselae in scratches and bites from cats, although some details of transmission are not completely understood. More than 90% of clinical cases occur in people who have been in contact with cats, most often kittens, and the majority of these patients report having been scratched, bitten or licked. In most cases, B. henselae probably enters the body through a scratch contaminated by flea feces. Organisms in feline saliva may be transmitted to people in bites, or abrasions that are licked by the cat. It is still unproven whether the bacteria in feline saliva come from the cat’s blood, or from flea feces ingested while grooming. However, one recent study found that bacteremic cats were more likely to have Bartonella DNA in oral swabs, compared to nonbacteremic cats. page 3 of 20 Cat Scratch Disease Entry of B. henselae through the eyelid or conjunctiva is thought to account for Parinaud oculoglandular syndrome, a form of cat scratch fever that affects the eye. This could occur when patients rub their eyes after contact with a cat. The authors of one article speculated that cases of hepatosplenic involvement without lymphadenopathy might be caused by ingestion. The possibility of transmission directly from fleas to humans (e.g., through flea bites) has also been proposed, but there is no evidence that this is possible. A few cases of cat scratch disease have occurred after exposure to inanimate objects such as crab claws, thorns, splinters and barbed wire, or after bites or scratches from animals other than cats. In some cases, the bacteria may have come from a cat that licked the wound. Scratches or bites from dogs have been implicated in a small number of B. henselae infections, and DNA from this organism (as well as B. vinsonii subsp. berkhoffii, B. quintana and B. bovis) has been detected occasionally in oral swabs from dogs. There are also a few reports of cat scratch disease associated with monkey bites. In a few cases, there is no history of animal contact, and the source of the organism is uncertain. Human infections with Bartonella species other than B. henselae are poorly understood, although bites or scratches have been implicated in some cases. One infection with B. vinsonii subsp. berkhoffii was diagnosed after a bite from a dog, and another after a bite from a coyote. A veterinarian became infected with B. vinsonii subsp. berkhoffii after a needlestick injury acquired while aspirating a neoplastic mass from a dog. Illness associated with B. alsatica was reported in a woman who had been scratched while butchering a wild rabbit. B. quintana DNA was found by PCR in an asymptomatic woman and in two feral cats, one of which had bitten the woman. In a number of these cases, only circumstantial evidence was available to support the route of transmission. Some animals could not be tested for Bartonella, while the feral cats with B. quintana were exposed to the same environment as the infected woman, and were unavailable for testing until 3 months after the bite. Disinfection Disinfectant susceptibility does not seem to have been published for Bartonella species including B. henselae, B. quintana or B. bacilliformis; however, there is no indication that these organisms are unusually resistant to inactivation. In many cases, bacteria can be disinfected with 70% ethanol, 1% sodium hypochlorite and 2% formaldehyde, as well as phenolic disinfectants, 2% aqueous glutaraldehyde and peracetic acid (0.001% to 0.2%). Physical methods of inactivation are moist heat of 121°C, held for 15 to 30 minutes, and dry heat of 160-170°C for 1-2 hours. Last Updated: July 2012 © 2012 Infection in Humans Incubation Period Cutaneous lesions usually develop at the inoculation site within 7 to 15 days after exposure, and lymphadenopathy is typically seen after 1-3 weeks. However, clinical signs have been reported as soon as 3 days and up to 50 days after exposure. Clinical Signs B. henselae appears to infect some immunocompetent people without causing clinical signs. Most others develop a self-limiting condition called cat scratch disease. Immunocompromised individuals infected with B. henselae may develop a more severe form of cat scratch disease, as well as bacillary angiomatosis and peliosis hepatis. Cat scratch disease In many cases, the first sign of cat scratch disease is the development of one or more small, reddish-brown, erythematous papules, pustules, macules, vesicles or ulcers at the inoculation site. These lesions disappear in 1-3 weeks, and may be mistaken for insect bites; however, they are not usually pruritic. The characteristic solitary lymphadenopathy or (less frequent) regional lymphadenopathy usually develops within a few weeks of exposure. Affected lymph nodes are often painful or tender, and the skin over the nodes can be warm, reddened and indurated. Cellulitis is, however, rare. Occasionally, the nodes may suppurate, especially when they are large. Lymphadenopathy usually lasts for a few weeks to a few months, and occasionally up to a year. Rarely, enlarged lymph nodes may persist longer. Cat scratch disease without lymphadenopathy is possible, but appears to be unusual in young, healthy patients. It is reported to be more common in elderly individuals and transplant patients. Other common symptoms are a low grade fever, malaise and fatigue. The fever usually disappears within 1-2 weeks but fatigue may persist for weeks or months. Less often, there may be other nonspecific signs such as headache, anorexia, vomiting, nausea, weight loss, generalized pain or a sore throat. Complications, systemic signs and atypical presentations are reported to occur in at least 5% and possibly up to 25% of patients, with an increased incidence in the elderly and people who are immunocompromised. Parinaud oculoglandular syndrome is the most common atypical presentation. It is thought to result from inoculation of the organism into the eye. This syndrome is characterized by nonpurulent unilateral conjunctivitis and/or conjunctival granuloma, together with preauricular, submandibular, or cervical lymphadenopathy. It usually resolves in several weeks without permanent damage. page 4 of 20 Cat Scratch Disease Neurological complications are uncommon. Encephalitis, the most common syndrome, has been reported in as many as 4-5% of patients in some series. It typically occurs 1-6 weeks after the classic symptoms, but cases without lymph node involvement, as well as cases preceding lymphadenopathy, have been reported. This condition may progress rapidly to seizures, coma with respiratory depression and other severe signs, but patients usually recover completely without permanent damage. Cranial or peripheral nerve involvement is less common than encephalitis. A wide variety of syndromes, such as transverse myelitis, transient facial nerve paresis, sensory loss, alterations in reflexes and motor deficits may be seen. Some neurological syndromes appear to be rare, and have been documented in only a few case reports in the literature. Ocular complications: Neuroretinitis is an uncommon but well-recognized condition in cat scratch disease. It is characterized by the sudden onset of painless visual loss, usually unilateral. Although the condition is temporary and resolves in months, some patients may have residual defects such as mildly decreased visual acuity, or abnormal color vision or contrast sensitivity. Various other ocular conditions such as anterior uveitis have also been attributed to B. henselae. Subretinal masses have been reported in HIVpositive patients. B. henselae bacteremia can result in endocarditis, most often in people with existing heart valve abnormalities. Disseminated disease with granulomatous hepatitis and/or splenitis has been reported in some patients. The usual signs are a persistent spiking fever and abdominal pain. Chills, weight loss, headache and myalgia may be seen. Lymphadenopathy may or may not be present. In most cases, the lesions and symptoms resolve within 6 months. Arthropathy has been reported in patients infected with Bartonella. The knee, wrist, ankle and elbow joints are most often involved. Arthropathy can persist for weeks after the lymphadenopathy has resolved. Osteomyelitis has been reported rarely. The osteolytic lesions are usually localized to one area, although cases of multifocal disease have been reported. The vertebrae and pelvic girdle are involved most often. The main symptoms are fever with pain and tenderness over the affected bone. Patients with bone involvement have usually recovered completely, although antibiotics were given in most cases. Last Updated: July 2012 © 2012 Various nonspecific rashes are reported infrequently. They are usually nonpruritic and resolve in days to weeks. Pulmonary involvement is rare. In most cases, it was characterized by pneumonia or pleural thickening and/or effusion. Patients have usually recovered completely, with a mean recovery time of 2 months. Other complications or syndromes have also been attributed to B. henselae, based on diagnosis by serology and/or PCR. They include fever of unknown origin, thrombocytopenic purpura (usually transient), hemolytic anemia, vasculitis, monoclonal gammopathy, biclonal gammopathy and glomerulonephritis, as well as soft tissue masses in the mammary gland, the liver or the spleen that may mimic neoplasia. Septic shock was reported in a transplant patient. Some of these complications seem to be rare, and have been documented in only a few case reports. Immunocompetent individuals with cat scratch disease usually recover without antibiotic treatment, and even complications generally resolve without sequelae. Although residual deficits have been reported, this is uncommon. Deaths are very rare. Endocarditis is usually the most serious concern; however, fatal encephalitis was reported in one child. In immunocompromised individuals, the clinical signs may be more severe; complications, bacteremia and atypical presentations are more common; and most cases are treated with antibiotics. Recurrent illness has been described in a few people with severe signs, including a transplant patient. The clinical signs recurred at 4-20 month intervals, and consisted of lymphadenopathy in one patient, lymphadenopathy and fever in another patient, and fever, headache, malaise and weight loss in two others. Bacillary angiomatosis and bacillary peliosis B. henselae can also cause bacillary angiomatosis (epithelioid angiomatosis) and peliosis hepatis. Although rare cases have been reported in immunocompetent individuals, these conditions occur mainly in those who are immunocompromised. Bacillary angiomatosis is a vascular proliferative disease of the skin and/or internal organs. It is most often an AIDS-related disease in people with a very low CD4 count. The most apparent symptoms are one to hundreds of cutaneous papules and nodules, which may resemble granulomas, Kaposi’s sarcoma (violaceous nodules), or lichenoid violaceous plaques. They vary in size from pinhead-sized to 10 cm in diameter. Subcutaneous nodules resembling a common abscess may also be seen. In addition, bacillary angiomatosis can involve the internal organs including the heart, brain, liver, spleen, bone, larynx, page 5 of 20 Cat Scratch Disease lymph nodes and gastrointestinal tract. The symptoms vary with the organ(s) affected, and may include neurological signs, bone pain, weight loss or symptoms related to massive visceral lymphadenopathy. Peliosis hepatis is a rare condition, caused by B. henselae as well as other pathogens, drugs and toxins. It is characterized by vascular proliferation in the liver, which can result in multiple blood-filled cysts and sinusoidal dilatation. The symptoms of peliosis hepatis may include fever, weight loss, abdominal pain, nausea, vomiting, diarrhea and hepatosplenomegaly. In some cases, this condition may be an incidental finding at necropsy. Peliosis hepatis can be seen in some patients with bacillary angiomatosis. based on serology alone. The signs consisted of papules at the inoculation site, fever and regional lymphadenopathy. The organism was not cultured or detected by PCR. Regional lymphadenopathy was associated with B. alsatica infection in an elderly woman who had been scratched while butchering a wild rabbit. Bacteria consistent with Bartonella were identified by Warthin-Starry silver staining in the enlarged lymph node, and these bacteria stained for B. alsatica by immunohistochemistry. PCR on the lymph node was also positive for this organism. Her condition responded to doxycycline. B. rochalimae was isolated from the blood of a person who developed an acute febrile illness with a diffuse macular rash, mild anemia and splenomegaly, soon after returning to the U.S. from a trip to South America. The infection responded to a short course of levofloxacin. A macaque that was inoculated with this organism had bacteremia and a decreased hematocrit. B. washoensis was isolated from the blood of a woman with fever, chills, headache, nausea, joint pain, an episode of vomiting, epigastric and lower left sided abdominal pain, and signs of meningitis. The symptoms improved after treatment with moxifloxacin, but persistent body aches and bone pain were still reported after 2 months. Both B. melophagi and B. henselae were isolated from the blood of a person who developed a relatively large (“hand-sized”), nonpruritic, red, cutaneous plaque, followed by a febrile illness with neutropenia, myalgia, neurological signs and joint pain. The illness waxed and waned at 3-4 week intervals. A heart murmur with mild aortic insufficiency and mild mitral regurgitation were also identified. Babesia microti, Anaplasma phagocytophilum and Borrelia burgdorferi were ruled out. Some improvement was seen with drugs effective for Bartonella (rifampin and azithromycin), but the symptoms did not resolve until cefuroxime was also added. In another case reported in the same paper, B. melophagi was isolated from the blood of a woman who had residual fatigue and muscle weakness, 6 months after an episode of pericarditis of uncertain etiology. No further information was given for the second case. B. tamiae was cultured from the blood of three patients enrolled in a prospective study to determine the etiology of febrile illnesses in Thailand. The clinical signs consisted of fever and nonspecific signs such as fatigue and headache, as well as anemia and mild liver function abnormalities. One patient had a maculopapular Other zoonotic Bartonella Additional zoonotic Bartonella spp. have been reported in people with various illnesses. A number of these case reports are described below. The type of evidence presented for the involvement of Bartonella in the condition, as well as the strength of the evidence, varies between cases. Endocarditis has been attributed to several species of Bartonella, and might also be caused by others. This condition occurs most often in people with pre-existing abnormalities of the heart valves. Most cases have been caused by B. henselae or the human pathogen B. quintana, but culture or PCR evidence has linked B. elizabethae, B. koehlerae, B. vinsonii subsp. berkhoffii, B. vinsonii subsp. arupensis, B. washoensis and B. alsatica to a few cases. Additional cases have been diagnosed based on serology alone. A B. vinsonii subsp. berkhoffii infection was reported in a veterinarian who sustained a needlestick injury while aspirating a neoplastic mass from a dog. There was no evidence of infection 5 days after exposure, but DNA from the organism was detected in the veterinarian’s blood at 34 days, after he reported frequent headaches, fatigue and intermittent paresthesia. B. vinsonii subsp. berkhoffii was also isolated from his blood, and seroconversion occurred. The symptoms resolved after treatment with doxycycline and rifampin. While the evidence suggests that the dog was the source of the infection, this could not be proved. Only one tissue sample was available for testing from the dog, and although B. vinsonii subsp. berkhoffii DNA was detected, it was of a different genotype. Antibodies to B. vinsonii (subspecies not identified) were also found in a child with fever and regional lymphadenopathy, who had been bitten by a dog (of unknown Bartonella status) 3 weeks earlier. B. clarridgeiae was suggested as the cause of cat scratch disease symptoms in at least three people, Last Updated: July 2012 © 2012 page 6 of 20 Cat Scratch Disease rash that had lasted 22 days, while another had a transient petechial rash. The report did not indicate whether the patients responded to antibiotics, or what other agents were ruled out. However, the organisms isolated from all three patients caused illness when inoculated into mice, and DNA was detected in the lesions in these animals. PCR assays detected DNA from B. vinsonii subsp. arupensis, B. elizabethae, B. rattimassiliensis and B. tribocorum in other febrile patients in this study. Further investigations of the latter cases have not been published. B. vinsonii subsp. arupensi was isolated from the blood of a U.S. cattle rancher who had high fever, headache, myalgia and neurological signs. The condition responded to treatment with ceftriaxone and prednisone. The rancher had a history of a relapsing rheumatologic syndrome with vasculitis and neurological signs, which was responsive to corticosteroids. The authors of this study concluded that his symptoms were consistent with his previously diagnosed condition, and the contribution of the Bartonella to the symptoms was uncertain. Communicability There is no evidence that B. henselae infections can be transmitted from person to person by casual contact. B. henselae was cultured from human RBC units that had been inoculated with this organism and stored at 4ºC for 35 days. The authors of this study suggest that blood transfusions might be able to transmit this organism. Diagnostic Tests Cat scratch disease is often diagnosed by the history and physical examination, with supporting evidence from laboratory tests. Providing definitive evidence for the involvement of Bartonella spp. in a medical condition may be difficult. Diagnostic tests for this organism have limitations, and many healthy people are seropositive. Bartonella spp. can sometimes be cultured from blood or tissues; however, these organisms are fastidious and isolation can be difficult. Conventional blood cultures from immunocompetent patients without systemic disease are often negative for B. henselae. Bartonella are usually cultured on specialized media such as fresh chocolate agar or brain–heart infusion agar enriched with blood. Some new media introduced in research laboratories or reported in the literature may increase the probability of detecting these organisms. B. henselae can take from 9 days to 6-8 weeks to form visible colonies. Multilocus sequence typing (MLST) and multiple locus variable number tandem repeat analysis (MLVA) have been used to identify genotypes of B. henselae. Last Updated: July 2012 © 2012 PCR assays are also available, and can differentiate species of Bartonella. PCR is sometimes negative in infected individuals. Serological tests for B. henselae include various indirect immunofluorescence assays and enzyme-linked immunosorbent assays (ELISAs). A fourfold rise in titer or the presence of IgM suggests a recent infection. IgM antibodies to B. henselae have been reported to persist for less than three months, while IgG may be detected for more than two years. Cross-reactions can occur between species of Bartonella. Cross-reactions have also been reported with other organisms such as Chlamydia spp. and Coxiella burnetii. Biopsies are not used routinely for cat scratch disease, but they may be employed in some instances (e.g., when neoplasia must be ruled out). Histopathology is suggestive but not diagnostic. The lesions of cat scratch fever and bacillary angiomatosis differ; cat scratch fever is characterized by stellate abscesses, granulomas and lymphocytic infiltrates, while vascular proliferation is seen with bacillary angiomatosis. Organisms may be detected in tissues with Warthin-Starry silver stain and Brown-Hopps Gram stains. Bartonella spp. are Gram negative, small, curved, pleomorphic rods. Immunostaining has been used to identify the bacteria, especially in research. Imaging studies can aid the diagnosis of hepatosplenic involvement and other complications. Skin testing, using crude lymph node antigens, was employed in the past, but is no longer recommended. This technique was abandoned due to fears of transmitting other infectious agents such as hepatitis viruses. It was also poorly standardized, and less specific and sensitive than serology. Treatment Immunocompetent patients Most cases of cat scratch disease in immunocompetent individuals are self-limiting. Treatment is usually supportive and symptomatic. Suppurating nodes may be aspirated to remove pus and reduce the pain. Severely affected lymph nodes or persistent ocular granulomas are occasionally excised. Although B. henselae is sensitive to a number of antimicrobials in vitro, antibiotics are not consistently effective for cat scratch disease in immunocompetent individuals. Antibiotics (azithromycin) were demonstrated to reduce lymph node size in some patients in one randomized, double blind study, although this drug did not decrease the duration of the illness or have any other effect on clinical signs. Other evidence for antibiotic use in uncomplicated cases is limited or anecdotal, and some studies have demonstrated no benefit. Serious, potentially life-threatening complications, such as Bartonella endocarditis, are treated with antibiotics. Surgical excision and replacement of the involved valve may also be necessary. Patients with non-life-threatening page 7 of 20 Cat Scratch Disease complications are sometimes treated with antibiotics, even when there is no evidence of immunosuppression. This is usually based on the good responses of immunocompromised individuals to these drugs (see below). However, some physicians may recommend only conservative treatment for complications that usually resolve on their own. Morbidity and Mortality Although antibodies to B. henselae are expected to be more common in people exposed to cats, the seroprevalence rates reported in high risk groups vary widely. A study from Poland detected antibodies to B. henselae in 45% of veterinarians, 53% of cat owners and 48% of homeless alcoholics. The seroprevalence rate in veterinarians was 15% in Japan, while a U.S. study found that 7% of veterinarians had antibodies to either B. henselae or B. quintana. In contrast, antibodies to B. henselae were detected in only 2% of people associated with the veterinary profession in Taiwan, although 24% of cats were seropositive. A study from Austria reported that the seroprevalence was 23% in the general population, with no statistically significant correlation between seroprevalence and pet ownership or residence in a rural environment. Similarly, there was no statistically significant difference between people with or without exposure to cats in Greece, where the seroprevalence was 20% in healthy populations. Relatively few surveys have studied exposure to other Bartonella species. Antibodies to B. elizabethae are common in some areas. In Sweden, 14% of healthy blood donors had antibodies to this organism, while approximately 3% had antibodies to B. grahamii and 3% to B. henselae, and no donors were seropositive for B. vinsonii subsp. vinsonii. Antibodies to B. elizabethae were detected in approximately 10% of patients presenting to rural hospitals in Thailand, although only 4% had antibodies to B. henselae and 4% to B. vinsonii subsp vinsonii. Among intravenous drug users in the inner city area of Baltimore, Maryland, 33% had antibodies to B. elizabethae and 11% to B. henselae. One U.S. study reported that 57% of a population with more than 10 years of occupational animal exposure had antibodies to B. henselae, B. quintana or B. vinsonii subsp. berkhoffii. In this study, B. henselae or B. vinsonii subsp. berkhoffii was also detected by PCR (or isolated, in a few cases) in all study participants. The source of the participants was not specified; however, all reported intermittent or nonspecific chronic symptoms such as headache, fatigue, arthralgia, myalgia and ataxia. Exposure to Bartonella spp. Antibodies to B. henselae seem to be relatively common in human populations, and in some studies, most seropositive individuals report no apparent history of cat scratch disease. A number of studies, conducted in several countries, found seroprevalence rates varying from less than 1% to 25% or more in the general population. One study from Italy reported an unusually high rate of reactors: antibodies to B. henselae were detected in approximately 62% of children and adolescents who presented as outpatients to a clinic for health check-ups or minor illnesses, and who had no symptoms that might indicate bartonellosis. In this study, 8.5% of the participants had high titers, suggesting recent or ongoing infections. A study from Chile found antibodies in 13% of children, and 10% of technical and professional workers who cared for cats. Illness Cat scratch disease is not reportable in any country, and the incidence of illness is uncertain. The high seroprevalence in healthy people may indicate that asymptomatic or mild infections with B. henselae are common. One 1993 study, however, estimated that 22,00024,000 cases of cat scratch disease may occur each year in the U.S. Most clinical cases are thought to involve children, although an increasing number have been identified in adults. In the U.S., cat scratch disease is most frequently seen between July and January, with the greatest number of hospitalizations between July and October. In France, one study found that the highest incidence was from September to April, with a peak in April. Seasonality in temperate regions in thought to be caused by the seasonal concentration of births, the acquisition of kittens as pets, Immunocompromised patients B. henselae infections in immunocompromised patients, including bacillary angiomatosis, usually respond well to various antibiotics. Uncomplicated cat scratch disease is treated in most cases, due to the elevated susceptibility to severe illness and complications. Prolonged treatment (4-6 months) has been used in patients who relapse. Prevention Bites and scratches from cats, particularly kittens, should be avoided. Rough play with kittens is inadvisable, and any bites or scratches should immediately be washed with soap and water. Declawing does not appear to affect transmission, but keeping the nails clipped has been suggested by some sources. Cats should be discouraged from licking a person’s skin, particularly the eyes, face and areas with abrasions or other open wounds. Hand washing after contact with a cat might be helpful. The ability of cats to transmit B. henselae is transient, and authorities do not recommend removing them from the household. The efficacy of antibiotics in eliminating B. henselae bacteremia in cats is uncertain (see Treatment in Animals, below). The 2009 Guidelines for Preventing Opportunistic Infections Among HIV-infected Adults and Adolescents note that there is no evidence that routine culture or serological testing of healthy cats for Bartonella provides any benefit for owners. Flea control decreases the risk that household cats will acquire B. henselae or transmit it to other cats. Last Updated: July 2012 © 2012 page 8 of 20 Cat Scratch Disease and peaks in the flea population. Cat scratch disease is not thought to be seasonal in tropical regions. In immunocompetent individuals, cat scratch disease is usually self-limiting and benign, although the symptoms may last for 1-5 months and occasionally longer. Significant illness is reported to occur in 5-10% of cases, usually from neurological signs or multisystem disseminated disease. Nearly all individuals, including those with neurological involvement, recover fully, and deaths are very rare. Endocarditis is usually the most serious complication. It has a reported prevalence of 0-3% in northern and central Europe (studies in France, Germany, Sweden and the U.K.), and 10% or greater in northern Africa. Reinfection seems to be infrequent. Complications, systemic illnesses and bacillary angiomatosis are more likely to develop in people who are immunocompromised. Bacillary angiomatosis and other conditions can be fatal in this population if left untreated. However, most immunocompromised individuals recover fully, provided the disease is treated appropriately. In one review, 28% of solid organ transplant recipients developed localized cat scratch disease, and 72% had disseminated infections. In this study, all patients with cat scratch disease and 19 of 21 patients with disseminated bartonellosis were cured with antibiotics. Two cases of endocarditis were fatal. Infections in Animals Species Affected Bartonella henselae Cats and other felids are the reservoir hosts for B. henselae. Organisms have been detected, by culture or PCR, in domesticated cats, cheetahs (Acinonyx jubatus), African lions (Panthera leo), cougars (Felis concolor; also known as pumas or mountain lions), bobcats (Lynx rufus) and wildcats (Felis silvestris). B. henselae has also been reported occasionally, by PCR or culture, in dogs, horses, cattle, feral pigs, seals, whales and porpoises Armadillos are susceptible to experimental infection. Mice can be infected under some laboratory conditions. Bartonella clarridgeiae and Bartonella koehlerae Cats are thought to be the reservoir hosts for B. clarridgeiae and possibly B. koehlerae. Both organisms have been detected rarely in dogs. DNA from B. koehlerae was found in feral pigs. Bartonella vinsonii subsp. berkhoffii B. vinsonii subsp. berkhoffii infects dogs and wild canids including coyotes (Canis latrans), gray foxes (Urocyon cinereoargenteus) and island foxes (Urocyon litorralis). This organism is thought to maintained in canids, and both dogs and coyotes have been suggested as reservoir hosts. DNA from B. vinsonii subsp. berkhoffii was detected in a horse and in feral pigs. Last Updated: July 2012 © 2012 Bartonella rochalimae B. rochalimae has been found in dogs and wild canids, including red foxes (Vulpes vulpes), gray foxes, island foxes, coyotes and a wolf (Canis lupus), as well as in raccoons (Procyon lotor) and various rodents including rats, shrews and gerbils. Bartonella bovis and Bartonella chomelii Cattle are the reservoir hosts for B. bovis (formerly B. weisii). This organism has been isolated or detected by PCR in a few cats and dogs, and some asymptomatic horses were seropositive. B. chomelii has been found in cattle. Bartonella melophagi B. melophagi has been reported in sheep. Bartonella alsatica B. alsatica has been found in rabbits. Bartonella capreoli and Bartonella schoenbuchensis B. capreoli and B. schoenbuchensis have been detected in deer. B. capreoli has also been isolated from elk (Cervus elephas), and B. schoenbuchensis from a cow. Bartonella species found in rodents Numerous Bartonella species have been detected in mice, rats, voles, shrews, ground squirrels, chipmunks, gerbils, jerboas, jirds and other rodents. Bartonella spp. reported to have rodent reservoir hosts include B. vinsonii subsp. arupensis, B. vinsonii subsp vinsonii, B. birtlesii, B. doshiae, B. peromysci, B. phoceensis, B. rattimassiliensis, B. talpae, B. taylorii, B. tribocorum, B. grahamii, B. elizabethae, B. queenslandensis and B. washoensis, as well as newly proposed species such as B. japonica sp. nov. and B. silvatica sp. nov. B. vinsonii subsp. arupensis, B. elizabethae, B. grahamii, B. taylorii and B. washoensis have also been detected in a few dogs. Many cats in Sweden are seropositive for B. elizabethae. Bartonella tamiae The reservoir host for B. tamiae is not known, although rats have been proposed. Isolates from humans caused illness in experimentally infected laboratory mice. Bartonella quintana B. quintana, a pathogen maintained in human populations, has been reported from a few cats and dogs. Bartonella in other animals Bartonella species or their DNA have also been detected in other mammals including North American river otters, kangaroos, wild badgers (Meles meles) and bats. Incubation Period In experimentally infected cats, cutaneous lesions may appear at the inoculation site within 2 days. Fever was first seen 2 to 16 days after inoculation. page 9 of 20 Cat Scratch Disease Clinical Signs B. henselae infections were reported in two cats with fatal pyogranulomatous myocarditis and diaphragmatic myositis at an animal shelter. Ten cats at this shelter developed fever, lethargy and diarrhea after a litter of flea-infested cats entered the facility. Feline leukemia virus (FeLV), feline panleukopenia virus, and feline immunodeficiency virus (FIV) were ruled out. One kitten died after developing acute respiratory distress, and an 8month-old cat, which had been in contact with the litter, died acutely 2 weeks later. Bacteria were found in inflammatory foci in the heart of both cats, as well as the diaphragm of one cat. These bacteria were identified as B. henselae by immunohistochemistry. PCR detected B. henselae DNA in the heart of one cat, and in multiple tissues including heart and diaphragm of the other cat. B. vinsonii subsp. berkhoffii was detected in lesions from a cat with recurrent osteomyelitis. Salmonella enterica subsp. enterica was also isolated from a bone marrow aspirate. The condition responded to treatment with azithromycin and amoxicillin-clavulanate. A number of studies have investigated whether B. henselae might be associated with stomatitis or gingivitis. In a study from Japan, the incidence of lymphadenopathy and gingivitis was significantly increased in cats seropositive for both FIV and B. henselae, compared to cats with antibodies only to FIV. A Swiss study reported a correlation between seropositivity to B. henselae and stomatitis. In a recent study that examined sick cats presented to a U.S. referral hospital, Bartonella was cultured more often from the blood of cats with gingivostomatitis than cats without this condition, although there was no correlation with seropositivity for B. henselae or B. clarridgeiae. However, one study reported no statistically significant relationship between gingivostomatitis and the prevalence of Bartonella DNA in blood samples, while another found no correlation with DNA in oral swabs. Similarly, a study of healthy shelter cats found no significant correlation between stomatitis and the prevalence of either antibodies to Bartonella spp. or DNA, when pairmatched samples were analyzed. One study reported that the presence of antibodies to B. henselae was correlated with an increased incidence of various unspecified urinary tract diseases. A newer study found a weak association between seropositivity, but not bacteremia, and idiopathic lower urinary tract disease. In this study, there was no correlation with urolithiasis or chronic kidney disease. The importance of Bartonella spp. as pathogens in animals is still unclear. Most infections appear to be asymptomatic. Some experimental infections, case reports and studies have suggested possible links to disease, but other studies have been unable to substantiate a role for Bartonella. Investigations are complicated by the high prevalence of infections in healthy animals, the uncertainties in diagnostic testing for these organisms, and the possibility of co-infection with other microorganisms. Cats Naturally-infected bacteremic cats are usually asymptomatic. Some studies have suggested that B. henselae might be pathogenic under some circumstances, but at present, definitive evidence is lacking. In experimental studies, most cats inoculated with B. henselae remained asymptomatic or had only mild clinical signs. In one experiment, cats developed inflammatory swellings or pustules at the inoculation site. Other clinical signs reported in experimentally infected cats were lymphadenopathy, myalgia and transient fever with lethargy and anorexia during febrile periods. Transient mild behavioral or neurological dysfunction, consisting of disorientation, nystagmus, hypersensitivity to stimuli, decreased responsiveness to environmental stimuli, or increased aggressiveness, as well as mild transient anemia, eosinophilia, and reproductive disorders have also been reported. In a recent study, no cats inoculated intravenously with B. henselae became ill, although bacteremia was detected in all cats. However, 3 of 6 cats exposed to B. henselae-infected fleas developed fever and inappetence. One of these cats was euthanized, as it became severely ill, and myocarditis was found at necropsy. There was some evidence that this cat may have failed to mount an adequate immune response: it had the lowest IgM titer to Bartonella, and was the only cat that did not have detectable IgG to this organism. No clinical signs have been reported in cats inoculated with B koehlerae or B. rochalimae. Two cats inoculated with B. quintana seroconverted with no evidence of bacteremia. A limited number of case reports and case series in naturally infected cats suggest that B. henselae or other Bartonella species might cause disease. Other studies have found no link to illness. A few case reports have attributed cardiac conditions, especially endocarditis, to Bartonella. B. henselae DNA was detected by PCR in the diseased heart valves of two cats that died of endocarditis. B. henselae was also isolated from the blood of a young cat with aortic valve endocarditis, and antibiotic treatment resulted in total resolution of the heart murmur and valvular lesion. Last Updated: July 2012 © 2012 page 10 of 20 Cat Scratch Disease A possible association between B. henselae and uveitis was proposed, after antibodies to this organism were found in the serum and aqueous humor of an immunocompetent cat with uveitis, which responded clinically to doxycycline. In a follow-up study, anti-Bartonella IgG was found in the aqueous humor of 7 of 49 client-owned cats with uveitis, and 0 of 49 healthy shelter cats. Four of 9 experimentally infected cats also had IgG antibodies in the aqueous humor. Uveitis was not correlated with antibodies in the serum. Two newer studies were unable to substantiate a link between uveitis and either seroprevalence or bacteremia. Unexplained cataracts were reported in SPF cats from a commercial vendor within a year after the cats became naturally infected with Bartonella. The relationship between the cataracts and the infection (if any) is not known, and this association may be coincidental. One study found no correlation between neurological signs and B. henselae or B. clarridgeiae bacteremia. There was also no correlation with antibodies to these organisms. Another study detected no difference in seroprevalence or the magnitude of antibody titers to B. henselae, in a comparison of cats with neurological disease, cats with non-neurological illnesses and healthy cats, when age and flea exposure were controlled. However, one retrospective study reported evidence of local antiBartonella antibody production in the central nervous system (CNS). These antibodies were detected in 31% of cats that had neurological signs together with serological or DNA evidence of Bartonella infection. A small number of cats had both B. henselae DNA in the CSF and Bartonellaspecific IgG in the cerebrospinal fluid. The findings are not conclusive, as Bartonella DNA can also be found in the brain of healthy cats; however, the authors suggest that further studies might be warranted. Studies reported no evidence for B. henselae in the lesions from 26 cats with peliosis hepatis, or 14 cats with plasmacytic pododermatitis. One study reported no evidence for Bartonella as a cause of chronic rhinosinusitis in cats. Dogs No clinical signs other than transient fever were reported in dogs inoculated with B. vinsonii subsp. berkhoffii. Two dogs inoculated with B. rochalimae also remained asymptomatic, with the exception of inflammation at the inoculation site. However, Bartonella spp. have been suggested as possible etiologic agents in some case reports. As with cats, it is difficult to establish a Last Updated: July 2012 © 2012 causative role, especially for organisms maintained in dogs, such as B. vinsonii subsp. berkhoffii. Bartonella spp. have been detected, by PCR or culture, in a few cases of endocarditis in dogs. Reported organisms include B. vinsonii subsp. berkhoffii, B. henselae, B. clarridgeiae, B. washoensis, B. quintana and B. rochalimae. B. koehlerae DNA was found in the aortic valve of another dog that died of endocarditis; however, E. coli was also cultured from aortic valve tissue. Additional cases of Bartonella-associated endocarditis have been suggested based on serology alone. B. vinsonii subsp. berkhoffii was implicated in a case of myocarditis. One dog infected with B. vinsonii subsp. berkhoffii developed clinical signs resembling human bacillary angiomatosis, after treatment with immunosuppressive drugs for pancytopenia. The condition was characterized by widespread, round to oval, erythematous, angioproliferative skin nodules. B. vinsonii subsp. berkhoffii DNA was found in the skin lesions, as well as in the blood. Bacteria consistent with Bartonella were also detected in the lesions, although some bacteria were either close to or within the endothelial cells. Azithromycin treatment was effective, with clinical resolution beginning within 2 days of starting the antibiotic. Bartonella spp. DNA was detected in the enlarged submandibular lymph node from a dog that developed fever, facial and cervical edema, and granulomatous lymphadenitis of the left regional lymph nodes, soon after a tick bite to the ear. Bacteria consistent with Bartonella were also detected in the node by Warthin–Starry silver staining. The dog did not have antibodies to Ehrlichia canis, Babesia canis, Rickettsia rickettsii or various fungi, but it was seropositive for B. vinsonii subsp. berkhoffii. Treatment with enrofloxacin for three weeks resulted in resolution of the fever and edema, and decreased lymph node size. Bartonella spp. were detected in a few case reports of liver disease. B. henselae DNA was found in the liver of one dog with peliosis hepatis (blood-filled cysts and cavities in the liver). DNA from this organism was also identified in two dogs with granulomatous hepatitis. Both dogs were treated with antibiotics for bartonellosis. One dog progressed to hepatic cirrhosis in spite of treatment. The other dog improved clinically, although the clinical signs appeared to recur when it was taken off azithromycin. It was apparently stable on this drug for approximately a year, then deteriorated and was euthanized. Other drugs and page 11 of 20 Cat Scratch Disease vitamins had also been administered by the owner. Limited necropsy results suggested death might have been caused by a toxic insult to the liver. B. clarridgeiae DNA was found in the liver of a dog with lymphocytic hepatopathy. This dog responded to treatment with azithromycin (for bartonellosis), prednisone and other drugs, and remained well for a year, but then developed signs consistent with liver failure before being lost to follow-up. In a dog with pyogranulomatous lymphadenitis, arthritis consistent with immune-mediated polyarthropathy, protein-losing nephropathy and conjunctivitis, B. henselae DNA was found in blood samples and in an affected lymph node. The dog had no antibodies to Bartonella or to several other organisms (Anaplasma phagocytophilum, Borrelia burgdorferi, Dirofilaria immitis, Ehrlichia canis and Rickettsia rickettsii), and culture of the joints was negative. The conjunctivitis in one eye initially worsened despite treatment with carprofen, doxycycline, enalapril and an ophthalmic solution containing neomycin, polymyxin, and dexamethasone. However, all clinical signs later resolved after a 6-week course of doxycycline. Another case of pyogranulomatous lymphadenitis attributed to Bartonella was based on positive serology and the detection of B. henselae DNA in blood and lymph nodes, together with negative bacterial and fungal cultures and the exclusion of seroreactivity to various fungi and Anaplasma phagocytophilum, Borrelia burgdorferi, E. canis, and R rickettsii. The dog was treated with a number of antibiotics over the course of the illness. Initial treatment with enrofloxacin, metronidazole and carprofen was unsuccessful; however, the clinical signs later resolved with a 7-day course of enrofloxacin and carprofen. When signs recurred 4 months later, the dog was treated for Bartonella with azithromycin and doxycycline. This resulted in limited improvement, but the clinical signs resolved with the addition of an immunosuppressive dose of prednisone. B. henselae and B. vinsonii subsp. berkhoffii were both isolated from the blood of a 4-year-old dog with a 2-year history of joint pain progressing to pelvic limb ataxia and refusal to walk. B. vinsonii subsp. berkhoffii was isolated from joint fluid. The condition was partially responsive to non-steroidal anti-inflammatory medications, and became progressively worse despite treatment with antibiotics for bartonellosis, including two 7-week courses of azithromycin. Bartonella spp. were still isolated from the blood and synovial fluid after treatment. Last Updated: July 2012 © 2012 Other case reports in the literature describe the isolation of B. vinsonii subsp. berkhoffii, or its detection by PCR, in syndromes as diverse as neoplasia, seroma after a traumatic injury, and panniculitis. One retrospective survey reported the diagnostic findings in sick dogs that also had antibodies to B. vinsonii subsp. berkhoffii. The diagnoses encompassed a diverse group of conditions, with most syndromes reported in only one to a few dogs. They included endocarditis, myocarditis, lymphadenitis, polyarthritis, cutaneous vasculitis, meningoencephalitis and other neurological syndromes, immune-mediated hemolytic anemia/immune thrombocytopenia, and ocular signs (anterior uveitis, chorioretinitis, ocular hemorrhage, and retinal detachment associated with hypertension). Thrombocytopenia was detected in approximately half of the dogs, and anemia in a third. A wide variety of antibiotics were used, and most but not all cases responded to treatment. After treatment, titers to Bartonella were no longer detected in the subset of cases where titers were measured. Whether Bartonella had a role in any of the cases was not established. In one case report, B. vinsonii subsp. berkhoffii DNA was found in a granulomatous nasal mass from an afebrile dog with rhinitis and proteinlosing nephropathy. No bacteria could be identified in the lesion by any technique, including Warthin–Starry silver staining. The dog had antibodies to both B. vinsonii subsp. berkhoffii and Ehrlichia canis, and E. canis DNA was detected in the blood 9 months after the mass was removed. The clinical signs resolved after removal of the mass and treatment with doxycycline for 30 days. In a recent case control study of dogs with idiopathic rhinitis, no dogs had antibodies to B. henselae or B. vinsonii subsp berkhoffii, and there was no evidence for these organisms by PCR. This study does not rule out the possibility that some cases of rhinitis are caused by Bartonella, but suggests that it is not a common etiology. Cattle The effect of Bartonella infections in cattle, if any, is unknown. Because B. bovis is very common in some herds, it is difficult to attribute clinical signs to this organism. B. bovis was suggested as the cause of endocarditis in two older cows. These animals had high antibody titers to this organism, and DNA was detected in the lesions. One study of a dairy herd suggested that adverse effects on health and reproductive success are uncommon. In this herd, there was no correlation between bacteremia and milk yield, milk cell count or various parameters of reproductive success. Fewer page 12 of 20 Cat Scratch Disease bacteremic cows retained the placenta, and the interval from calving to first artificial insemination was shorter. Horses Four horses inoculated intradermally with an equine isolate of B. henselae developed injection site reactions (mild edema, sensitivity and pruritus, sometimes accompanied by purulent drainage), and had mild, nonpainful, unilateral enlargement of the regional lymph node, without fever. Three of the horses also had mild to moderate limb edema. One of these horses had evidence of concurrent infection with B. vinsonii subsp. berkhoffii, apparently acquired during the experiment. In the same experiment, four horses inoculated intradermally with a bovine isolate of B. bovis had milder injection site reactions consisting of sensitivity and mild edema. Two horses developed mild, unilateral, nonpainful regional enlargement of the regional lymph node, two horses had nonpruritic urticaria, and one horse had mild colic and mild hind limb edema. However, only one horse had evidence of infection with B. bovis (transient low titers to this organism). Possible involvement of B. henselae was suggested in a few case reports: B. henselae DNA was detected in the tissues of an aborted equine fetus that had necrosis and vasculitis in multiple tissues. Gram-negative bacteria, which stained with Warthin-Starry silver stain and labeled with a monoclonal antibody to B. henselae, were found in many of the inflammatory lesions. No known agents of equine abortion could be detected in this fetus. The mare had no history of clinical signs or prior abortions. Other mares on the same farm successfully carried foals to term. In one report, B. henselae was detected in blood samples from a horse with chronic arthropathy and another horse with vasculitis. Whether Bartonella had any role in these conditions is unclear. The horse with vasculitis had a high antibody titer to Streptococcus equi, and was diagnosed as having purpura hemorrhagica. In the horse with chronic arthropathy, the clinical signs did not resolve after treatment with antibiotics effective against Bartonella. Rodents Experimentally infected rodents have remained asymptomatic in some studies. Granulomatous hepatitis was the only necropsy lesion in rodents inoculated with large numbers of bacteria. However, the incidence of fetal death and placental vasculitis was increased in mice infected with B. birtlesii. Inoculation of mice with two B. tamiae isolates from humans resulted in axillary and inguinal lymphadenopathy, ulcerative skin lesions and subcutaneous masses on the thorax. Myocarditis, lymphadenitis with vascular necrosis, and granulomatous hepatitis and nephritis were reported at necropsy. Mice Last Updated: July 2012 © 2012 inoculated with another human isolate of B. tamiae (from a patient with less severe symptoms) developed dermatitis and granulomas in the kidneys, but did not have lymphadenitis. Non-human primates In one experiment, simian immunodeficiency virus (SIV)-infected macaques inoculated with B. henselae remained asymptomatic. These monkeys did not become bacteremic or seroconvert. In another experiment, two macaques became febrile and developed subcutaneous purple-red spots at the inoculation site. The significance of this finding is unclear, as B. henselae was not recovered from the regional lymph nodes and the animals did not seroconvert. Communicability B. henselae does not seem to be transmitted between cats by casual contact, in the absence of fleas. Infected cats can infect humans with B. henselae, via scratches and bites. Other animal species also seem to be able to transmit Bartonella to humans. Diagnostic Tests A number of tests can be used to detect infection with Bartonella spp. Culture of blood or other tissues is the most definitive method; however, organisms cannot always be isolated from infected animals. Bartonella spp. may be easier to culture from some hosts (e.g., B. henselae in cats) than others. Even in cats, several attempts may be necessary to detect bacteria in the blood, as bacteremia can be intermittent. Bartonella spp. are fastidious, and isolation requires specialized media such as fresh chocolate agar or brain–heart infusion agar enriched with blood. Visible colonies of B. henselae usually develop in 9 days to 6-8 weeks. Some new media introduced in research laboratories or reported in the literature may improve isolation of Bartonella spp., especially in species other than the reservoir hosts. In specialized laboratories, genotypes of B. henselae can be identified by multilocus sequence typing and multiple locus variable number tandem repeat analysis. PCR assays are commonly used to detect Bartonella spp. in research, and may be available in some laboratories. One sensitive technique employs isolation in a Bartonella α-Proteobacteria growth medium (BAPGM) based enrichment culture, followed by multiplex real-time PCR. Contamination with flea feces on the skin, or other sources of Bartonella organisms or DNA, can cause false positive results in PCR tests and culture. PCR inhibitors may be present in some biological samples. Immunocytochemical and immunohistochemical methods can detect Bartonella spp. in lesions. These tests may not be available outside research laboratories. Serological tests for B. henselae include immunofluorescent antibody, ELISA and immunoblotting (Western blotting); however, there is only limited page 13 of 20 Cat Scratch Disease experience with immunoblotting. In cats with uveitis, tests should include the demonstration of intraocular Bartonellaspecific antibody production. False-positive test results appear to be common in all serological assays, and authors recommend the use of serology in conjunction with blood culture or PCR testing. Some infected cats and dogs do not have antibodies to Bartonella, although the organism can be identified in blood and/or tissues by culture or PCR. Conversely, IgG antibodies to Bartonella can persist in infected animals even after the infection has been cleared. Treatment Treatment is usually recommended only for animals that are ill. Antibiotic resistant isolates of Bartonella spp. have occasionally been reported. Routine treatment of asymptomatic, bacteremic cats is not recommended as a method of zoonosis prevention. No treatment regimen is proven to be consistently effective in eliminating B. henselae bacteremia in cats, although some antibiotics have apparently been successful in individual animals. Documenting clearance of the organism is difficult, because bacteremia fluctuates. Routine treatment might also promote the generation of antibiotic-resistant strains. Animals that have eliminated the organism, including cats, may be reinfected with other Bartonella species, and sometimes by different genotypes or strains. Prevention Flea control decreases the risk of B. henselae transmission between cats. One experiment specifically examined a once-a-month flea control product (topical imidacloprid and moxidectin). In this experiment, six treated cats did not become infected with B. henselae after exposure to infected fleas, but six untreated cats became bacteremic. When using cats as blood donors, the possibility of transmission from infected animals should be considered. Infection with many Bartonella species is not well understood; however, arthropods are thought to be involved in all cases, and vector control should decrease transmission. Morbidity and Mortality Clinical cases do not seem to occur frequently in animals, but asymptomatic infections with Bartonella spp. are common, especially in reservoir hosts. Cats and other Felidae Asymptomatic infections with B. henselae are very common in cats. In studies from the U.S., Brazil, Ireland, the U.K., eastern Australia and other locations, the prevalence of bacteremia in cats varied from 3% to greater than 40%, and was as high as 70-72% in some populations by PCR. Bartonella DNA was detected in the saliva of a few percent of cats in some studies, but up to 60% in others. Young cats are more likely to be bacteremic than older animals. Feral cats are also more likely to be infected with Last Updated: July 2012 © 2012 B. henselae than pet cats. Bacteremia can last for weeks to months, and the number of bacteria in the blood can fluctuate greatly during this time. Intermittent B henselae or B clarridgeiae bacteremia was reported to persist for almost 15 months in some experimentally infected cats, with relapses occurring irregularly at one to 4.5 month intervals. Intermittent bacteremia has been reported for as long as 3 years in naturally infected cats, although it is possible that these cats were reinfected. Seasonality has been reported in temperate climates. In a study from the U.S., more than twice as many cats were reported to be bacteremic in September compared to June. While bacteremia is more common in young cats, older cats are more likely to be seropositive. Seroprevalence tends to be higher in warm, humid regions, where fleas are more common. In one 1995 survey, the overall seroprevalence in U.S. cats was 28%, with rates varying from a low of 4-7% in the Midwest, Rocky Mountain-Great Plains region and Alaska, to 34% in the Pacific Northwest, 37% in the south-central plains, 40% in coastal California, 47% in Hawaii and 55% in the Southeast. Internationally, studies using a variety of tests reported seroprevalence rates of 27% to 68% in the Philippines, eastern Australia, Brazil, Ireland, Italy and Turkey, and 1% or less in Sweden and Norway. More than 80% of the cats in some animal shelters may have antibodies to B. henselae. Antibodies to B. henselae are also common in other captive and wild members of the Felidae. In California zoos, antibodies to this organism were reported in 17% of cats of the genus Panthera (lions, tigers, leopards and jaguars), 18% of cheetahs and 47% of small wild cats of the genus Felis. Approximately 53% of wild bobcats and 35% of wild cougars tested in California, 18% of wild Florida panthers, and 28% of wild cougars from Texas were also seropositive. Overall, antibodies to B. henselae were found in 19% of cougars and 23% of bobcats in North, Central and South America. Among lions and cheetahs captured in Africa between 1982 and 2002, 5.2% of the lions and 5.9% of the cheetahs were bacteremic with B. henselae or an unidentified Bartonella, and antibodies to B. henselae were found in 17% of the lions and 31% of the cheetahs. In South Africa, another study reported antibodies to B. henselae in 29% of lions tested. B. clarridgeiae is thought to be less common in cats than B. henselae. This organism accounted for approximately 10% of the isolates from bacteremic cats in the U.S., and 30% in France and the Philippines. Another study reported that 21% of cats in the U.S. had B. clarridgeiae DNA in the blood, and 35% had DNA from B. henselae. In one study of shelter cats, however, antibodies to B. henselae were found in 8% of Michigan cats and antibodies to B. clarridgeiae in 18%, while 39% of California cats were seropositive for B. henselae and 52% for B. clarridgeiae. A survey of cats in Sweden reported that 25% were seropositive for B. elizabethae. B koehlerae is thought to be rare. page 14 of 20 Cat Scratch Disease Canidae Similarly to B. henselae in cats, seroconversion to B. vinsonii subsp. berkhoffii is reported to be lower in temperate than tropical regions. In various surveys, the seroprevalence in dogs was 1% in North Carolina, 12% in rural north-coastal California, 10% in Israel, 5% in Greece, 9% on Reunion Island, and as high as 65% in some areas of sub-Saharan Africa. Within some individual kennels, the seroprevalence can be as high as 93%. One study reported that, on average, approximately 9% of U.S. military working dogs had antibodies to B. vinsonii subsp. berkhoffii, with the highest seroprevalence in dogs from the southern and northeastern states, and low rates in dogs from the Midwest and mountain states. In a study from Turkey, antibodies to this organism were found in 3% of urban stray dogs, and 12% of shepherd and farm guard dogs in rural areas. In Morocco, the seroprevalence was 4% in pet dogs, and 36-47% in stray dogs, varying by region. Some surveys examined serum samples submitted from sick animals. In several studies from the U.S., the prevalence of antibodies to B. vinsonii subsp. berkhoffii in sick dogs ranged from less than 0.5% to as high as 11%. In Thailand, 38% of the sick dogs examined were seropositive, but DNA was not detected in any dog by PCR. One survey did not find antibodies to B. vinsonii subsp. berkhoffii in any serum samples submitted for diagnostic testing in southern Ontario and Quebec, Canada. Other species of Bartonella can also infect dogs. Overall Bartonella spp. seroprevalence was reported to be 10% in dogs from Colombia, 8% in Brazil, 5% in Sri Lanka and 0% in Vietnam. In various surveys worldwide, antibodies to B. henselae were found in 3–35% of dogs. One study from the US reported that 10% of the healthy dogs examined, and 27% of the sick dogs, were seropositive for this organism. Another U.S. study found antibodies to Bartonella spp. in approximately 3% of samples from sick dogs, with the vast majority of these dogs reacting to B. henselae, B. clarridgeiae or multiple species, and fewer than 0.5% reacting to B. vinsonii subsp. berkhoffii alone. Among wild canids, antibodies to B. vinsonii subsp. berkhoffii were detected in approximately 12% of gray foxes in West/ Central Texas; 10% of island foxes on Santa Rosa Island, California; and 35% or 76% of coyotes in California. Approximately 28% of the coyotes in the latter study had evidence of bacteremia, by PCR. Antibodies to B. rochalimae were found in 33% of gray foxes in West/Central Texas, 43% of gray foxes in northern California and 31% of island foxes on Santa Rosa Island. Cattle Infection with B. bovis seems to be common in cattle, especially beef breeds. One survey from North Carolina reported that 95% of the cattle tested were seropositive for B. bovis. Another study from the same state detected Bartonella DNA in 82% of beef cattle. In California, Bartonella bacteremia was found in 81–96% of beef cattle and 17% of dairy cattle. B. bovis was detected in 0.2% of Last Updated: July 2012 © 2012 dairy cows and 42.5% of beef cattle in Taiwan. In France, this organism was found in the blood of 59% of the animals in one dairy herd, with the highest prevalence (93%) in heifers. Despite the high prevalence, there were no adverse effects on reproductive function or health in this herd. Rodents and other small mammals Bartonella spp. may be common among wild rodents in urban locations. In urban Los Angeles, California, Bartonella DNA was found in 68% of blood samples from wild rats, and 44% of the PCR-positive blood samples were also culture positive. B. rochalimae was detected in 19% of these rats, and B. tribocorum in 58%. Several other rodent-associated species were also identified by PCR. Bartonella spp. can also be common in other wild animals, such as rabbits. One study detected Bartonella spp. in blood samples from 26% of exotic small mammals imported into Japan as pets. The prevalence was much higher in animals that had been captured from the wild (37%), compared to animals from breeders (approximately 3%). In animals bred for the pet trade, Bartonella was found only in Siberian chipmunks (Tamias sibiricus) from China. Among pet rodents captured from the wild, bacteremia was detected in approximately 39% of animals in the family Muridae, and 44% in the family Sciuridae, while no organisms were found in animals from the families Octodontidae and Erinaceidae. High prevalence was reported in the bushy-tailed jird, Sekeetamys calurus; (100%); large Egyptian gerbil, Gerbillus pyramidum (90%), greater Egyptian jerboa, Jaculus orientalis (81%), and lesser Egyptian jerboa, J. jaculus (75%). In contrast, the prevalence was only 10% in the Cairo spiny mouse (Acomys cahirinus). Post Mortem Lesions Lymphadenomegaly, inoculation site lesions and myocarditis were reported in some cats experimentally infected with B. henselae or B. clarridgeiae. Histopathologic lesions included lymph node hyperplasia, splenic follicular hyperplasia, lymphocytic cholangitis, and foci of lymphocytic, pyogranulomatous or neutrophilic inflammation in the liver, spleen, lungs, kidneys and heart. Some cats had small foci of hepatic or splenic necrosis. Granulomatous hepatitis has been reported in experimentally infected rodents. Mice inoculated with two human isolates of B. tamiae had myocarditis, lymphadenitis with vascular necrosis, and granulomatous hepatitis and nephritis at necropys. Mice inoculated with another human isolate of B. tamiae had dermatitis and granulomas in the kidneys, without lymphadenitis. Various lesions including endocarditis, granulomatous lesions, and bacillary angiomatosis, as well as areas of vasculitis and necrosis in an aborted fetus, have been reported in naturally infected animals with syndromes attributed to Bartonella. However, as this organism was not proven to be the cause of these syndromes, it remains possible that the lesions were not caused by Bartonella. page 15 of 20 Cat Scratch Disease Internet Resources Centers for Disease Control and Prevention (CDC) http://www.cdc.gov/healthypets/diseases/catscratch.ht m eMedicine.com - Cat scratch disease http://www.emedicinehealth.com/cat_scratch_disease/a rticle_em.htm http://emedicine.medscape.com/article/214100overview eMedicine.com - Bacillary angiomatosis http://emedicine.medscape.com/article/1051846overview Public Health Agency of Canada. Pathogen Safety Data Sheets http://www.phac-aspc.gc.ca/lab-bio/res/psds-ftss/indexeng.php The Merck Manual http://www.merck.com/pubs/mmanual/ The Merck Veterinary Manual http://www.merckvetmanual.com/mvm/index.jsp References Acha PN, Szyfres B (Pan American Health Organization [PAHO]). Zoonoses and communicable diseases common to man and animals. Volume 1. Bacterioses and mycoses. 3rd ed. WashingtonDC: PAHO; 2003. Scientific and Technical Publication No. 580. Cat-scratch disease; p. 78-81. Amersham Health. Peliosis hepatis [online]. The Encyclopaedia of Medical Imaging Volume IV:1. Available at: http://www.amershamhealth.com/medcyclopaedia/medical/vol ume%20IV%201/PELIOSIS%20HEPATIS.ASP.* Accessed 12 Oct 2004. Angelakis E, Billeter SA, Breitschwerdt EB, Chomel BB, Raoult D. Potential for tick-borne bartonelloses. Emerg Infect Dis. 2010;16(3):385-91. Bai Y, Cross PC, Malania L, Kosoy M. Isolation of Bartonella capreoli from elk. Vet Microbiol. 2011;148(2-4):329-32. Bai Y, Kosoy MY, Diaz MH, Winchell J, Baggett H, Maloney SA, Boonmar S, Bhengsri S, Sawatwong P, Peruski LF. Bartonella vinsonii subsp. arupensis in humans, Thailand. Emerg Infect Dis. 2012;18(6):989-91. Beard AW, Maggi RG, Kennedy-Stoskopf S, Cherry NA, Sandfoss MR, DePerno CS, Breitschwerdt EB. Bartonella spp. in feral pigs, southeastern United States. Emerg Infect Dis. 2011;17(5):893-5. Bemis DA, Kania SA. Isolation of Bartonella sp. from sheep blood. Emerg Infect Dis. 2007;13(10):1565-7. Ben-Ami R, Ephros M, Avidor B, Katchman E, Varon M, Leibowitz C, Comaneshter D, Giladi M. Cat-scratch disease in elderly patients. Clin Infect Dis. 2005 1;41(7):969-74. Bhengsri S, Baggett HC, Peruski LF, Morway C, Bai Y, Fisk TL, Sitdhirasdr A, Maloney SA, Dowell SF, Kosoy M. Bartonella seroprevalence in rural Thailand. Southeast Asian J Trop Med Public Health. 2011;42(3):687-92. Last Updated: July 2012 © 2012 Billeter SA, Levy MG, Chomel BB, Breitschwerdt EB. Vector transmission of Bartonella species with emphasis on the potential for tick transmission. Med Vet Entomol. 2008;22(1):1-15. Breitschwerdt EB. Feline bartonellosis and cat scratch disease. Vet Immunol Immunopathol. 2008;123(1-2):167-71. Breitschwerdt EB, Blann KR, Stebbins ME, Muñana KR, Davidson MG, Jackson HA, Willard MD. Clinicopathological abnormalities and treatment response in 24 dogs seroreactive to Bartonella vinsonii (berkhoffii) antigens. J Am Anim Hosp Assoc. 2004;40:92-101. Breitschwerdt EB, Kordick DL. Bartonella infection in animals: carriership, reservoir potential, pathogenicity, and zoonotic potential for human infection. Clin Microbiol Rev. 2000;13: 428-38. Breitschwerdt EB, Maggi RG, Sigmon B, Nicholson WL. Isolation of Bartonella quintana from a woman and a cat following putative bite transmission. J Clin Microbiol. 2007;45(1):270-2. Breitschwerdt EB, Maggi RG, Varanat M, Linder KE, Weinberg G. Isolation of Bartonella vinsonii subsp. berkhoffii genotype II from a boy with epithelioid hemangioendothelioma and a dog with hemangiopericytoma. J Clin Microbiol. 2009;47(6):1957-60. Brenner EC, Chomel BB, Singhasivanon OU, Namekata DY, Kasten RW, Kass PH, Cortés-Vecino JA, Gennari SM, Rajapakse RP, Huong LT, Dubey JP. Bartonella infection in urban and rural dogs from the tropics: Brazil, Colombia, Sri Lanka and Vietnam. Epidemiol Infect. 2012:1-8. [Epub ahead of print] Buchmann AU, Kempf VA, Kershaw O, Gruber AD. Peliosis hepatis in cats is not associated with Bartonella henselae infections. Vet Pathol. 2010;47(1):163-6. Celebi B, Taylan Ozkan A, Kilic S, Akca A, Koenhemsi L, Pasa S, Yildiz K, Mamak N, Guzel M. Seroprevalence of Bartonella vinsonii subsp. berkhoffii in urban and rural dogs in Turkey. J Vet Med Sci. 2010;72(11):1491-4. Chaloner GL, Harrison TG, Coyne KP, Aanensen DB, Birtles RJ. Multilocus sequence typing of Bartonella henselae in the United Kingdom indicates that only a few, uncommon sequence types are associated with zoonotic disease. J Clin Microbiol. 2011, 49(6):2132-7. Chang CC, Lee CC, Maruyama S, Lin JW, Pan MJ. Cat-scratch disease in veterinary-associated populations and in its cat reservoir in Taiwan. Vet Res. 2006;37(4):565-77. Chen TC, Lin WR, Lu PL, Lin CY, Chen YH. Cat scratch disease from a domestic dog. J Formos Med Assoc. 2007;106(2 Suppl):S65-68. Cherry NA, Liebisch G, Liebisch A, Breitschwerdt EB, Jones SL, Ulrich R, Allmers E, Wolf P, Hewicker-Trautwein M. Identification of Bartonella henselae in a horse from Germany. Vet Microbiol. 2011;150(3-4):414-5. Cherry NA, Maggi RG, Cannedy AL, Breitschwerdt EB. PCR detection of Bartonella bovis and Bartonella henselae in the blood of beef cattle.Vet Microbiol. 2009;135(3-4):308-12. Chinnadurai SK, Birkenheuer AJ, Blanton HL, Maggi RG, Belfiore N, Marr HS, Breitschwerdt EB, Stoskopf MK. Prevalence of selected vector-borne organisms and identification of Bartonella species DNA in North American river otters (Lontra canadensis). J Wildl Dis. 2010 ;46(3):947-50. page 16 of 20 Cat Scratch Disease Chmielewski T, Podsiadły E, Tylewska-Wierzbanowska S. Presence of Bartonella spp. in various human populations. Pol J Microbiol. 2007;56(1):33-8. Chomel BB, Kasten RW. Bartonellosis, an increasingly recognized zoonosis. J Appl Microbiol. 2010;109(3):743-50. Chomel BB, Kasten RW. Henn JB, Molia S. Bartonella infection in domestic cats and wild felids. Ann NY Acad Sci. 2006;1078: 410–15. Chomel BB, Kasten RW, Williams C, Wey AC, Henn JB, Maggi R, Carrasco S, Mazet J, Boulouis HJ, Maillard R, Breitschwerdt EB. Bartonella endocarditis: a pathology shared by animal reservoirs and patients. Ann N Y Acad Sci. 2009;1166:120-6. Colton L, Zeidner N, Lynch T, Kosoy MY. Human isolates of Bartonella tamiae induce pathology in experimentally inoculated immunocompetent mice. BMC Infect Dis. 2010;10:229. Comer JA, Flynn C, Regnery RL, Vlahov D, Childs JE. Antibodies to Bartonella species in inner-city intravenous drug users in Baltimore, Md. Arch Intern Med. 1996;156(21):2491-5. Cotté V, Bonnet S, Le Rhun D, Le Naour E, Chauvin A, Boulouis HJ, Lecuelle B, Lilin T, Vayssier-Taussat M. Transmission of Bartonella henselae by Ixodes ricinus. Emerg Infect Dis. 2008;14(7):1074-80. Crissiuma A, Favacho A, Gershony L, Mendes-de-Almeida F, Gomes R, Mares-Guia A, Rozental T, Barreira J, Lemos E, Labarthe N. Prevalence of Bartonella species DNA and antibodies in cats (Felis catus) submitted to a spay/neuter program in Rio de Janeiro, Brazil. J Feline Med Surg. 2011;13(2):149-51. Davis CP. Cat scratch disease (CSD or cat scratch fever). eMedicine.com; 2009. Available at: http://www.emedicinehealth.com/cat_scratch_disease/article_ em.htm. Accessed Jan 2012. De Souza Zanutto M, Mamizuka EM, Raiz R Jr, de Lima TM, Diogo CL, Okay TS, Hagiwara MK. Experimental infection and horizontal transmission of Bartonella henselae in domestic cats. Rev Inst Med Trop Sao Paulo. 2001;43:257-61. Diniz PP, Beall MJ, Omark K, Chandrashekar R, Daniluk DA, Cyr KE, Koterski JF, Robbins RG, Lalo PG, Hegarty BC, Breitschwerdt EB. High prevalence of tick-borne pathogens in dogs from an Indian reservation in northeastern Arizona. Vector Borne Zoonotic Dis. 2010;10(2):117-23. Diniz PP, Wood M, Maggi RG, Sontakke S, Stepnik M, Breitschwerdt EB. Co-isolation of Bartonella henselae and Bartonella vinsonii subsp. berkhoffii from blood, joint and subcutaneous seroma fluids from two naturally infected dogs. Vet Microbiol. 2009;138(3-4):368-72. Dowers KL, Hawley JR, Brewer MM, Morris AK, Radecki SV, Lappin MR. Association of Bartonella species, feline calicivirus, and feline herpesvirus 1 infection with gingivostomatitis in cats. J. Feline Med. Surg. 2010;12:314–21. Duncan AW, Maggi RG, Breitschwerdt EB. Bartonella DNA in dog saliva. Emerg Infect Dis. 2007;13(12):1948-50. Ebani VV, Bertelloni F, Fratini F. Occurrence of Bartonella henselae types I and II in Central Italian domestic cats. Res Vet Sci. 2012;93(1):63-6. Last Updated: July 2012 © 2012 Eremeeva ME, Gerns HL, Lydy SL, Goo JS, Ryan ET, Mathew SS, Ferraro MJ, Holden JM, Nicholson WL, Dasch GA, Koehler JE. Bacteremia, fever, and splenomegaly caused by a newly recognized Bartonella species. N Engl J Med. 2007 7;356(23):2381-7. Ferrés G M, Abarca V K, Prado D P, Montecinos P L, Navarrete C M, Vial C PA. [Prevalence of Bartonella henselae antibodies in Chilean children, adolescents and veterinary workers].Rev Med Chil. 2006;134(7):863-7. Ficociello J, Bradbury C, Morris A, Lappin MR. Detection of Bartonella henselae IgM in serum of experimentally infected and naturally exposed cats. J Vet Intern Med. 2011;25(6):1264-9. Florin TA, Zaoutis TE, Zaoutis LB. Beyond cat scratch disease: widening spectrum of Bartonella henselae infection. Pediatrics. 2008;121(5):e1413-25. Foley JE, Brown RN, Gabriel MW, Henn J, Drazenovich N, Kasten R, Green SL, Chomel BB. Spatial analysis of the exposure of dogs in rural north-coastal California to vector borne pathogens. Vet Rec. 2007;161(19):653-7. Fouch B, Coventry S. A case of fatal disseminated Bartonella henselae infection (cat-scratch disease) with encephalitis. Arch Pathol Lab Med. 2007;131(10):1591-4. Gary AT, Webb JA, Hegarty BC, Breitschwerdt EB. The low seroprevalence of tick-transmitted agents of disease in dogs from southern Ontario and Quebec. Can Vet J. 2006;47(12):1194-200. Gerrikagoitia X, Gil H, García-Esteban C, Anda P, Juste RA, Barral M. Presence of Bartonella species in wild carnivores of northern Spain. Appl Environ Microbiol. 2012;78(3):885-8. Gillespie TN, Washabau RJ, Goldschmidt MH, Cullen JM, Rogala AR, Breitschwerdt EB. Detection of Bartonella henselae and Bartonella clarridgeiae DNA in hepatic specimens from two dogs with hepatic disease. J Am Vet Med Assoc. 2003 1;222(1):47-51, 35. Gundi VA, Billeter SA, Rood MP, Kosoy MY. Bartonella spp. in rats and zoonoses, Los Angeles, California, USA. Emerg Infect Dis. 2012;18(4):631-3. Guptill L. Bartonellosis. Vet Microbiol. 2010;140(3-4):347-59. Guptill L. Feline bartonellosis. Vet Clin North Am Small Anim Pract. 2010;40(6):1073-90. Guzel M, Celebi B, Yalcin E, Koenhemsi L, Mamak N, Pasa S, Aslan O. A serological investigation of Bartonella henselae infection in cats in Turkey. J Vet Med Sci. 2011;73(11):1513-6. Hajjaji N, Hocqueloux L, Kerdraon R, Bret L. Bone infection in cat-scratch disease: a review of the literature. J Infect. 2007;54(5):417-21. Hawkins EC, Johnson LR, Guptill L, Marr HS, Breitschwerdt EB, Birkenheuer AJ. Failure to identify an association between serologic or molecular evidence of Bartonella infection and idiopathic rhinitis in dogs. J Am Vet Med Assoc. 2008;233(4):597-9. Henn JB, Chomel BB, Boulouis HJ, Kasten RW, Murray WJ, BarGal GK, King R, Courreau JF, Baneth G. Bartonella rochalimae in raccoons, coyotes, and red foxes. Emerg Infect Dis. 2009;15(12):1984-7. page 17 of 20 Cat Scratch Disease Henn JB, Gabriel MW, Kasten RW, Brown RN, Koehler JE, MacDonald KA, Kittleson MD, Thomas WP, Chomel BB. Infective endocarditis in a dog and the phylogenetic relationship of the associated "Bartonella rochalimae" strain with isolates from dogs, gray foxes, and a human. J Clin Microbiol. 2009;47(3):787-90. Henn JB, Liu CH, Kasten RW, VanHorn BA, Beckett LA, Kass PH, Chomel BB. Seroprevalence of antibodies against Bartonella species and evaluation of risk factors and clinical signs associated with seropositivity in dogs. Am J Vet Res. 2005;66(4):688-94. Henn JB, Vanhorn BA, Kasten RW, Kachani M, Chomel BB. Antibodies to Bartonella vinsonii subsp. berkhoffii in Moroccan dogs. Am J Trop Med Hyg. 2006;74(2):222-3. Hjelm E, McGill S, Blomqvist G. Prevalence of antibodies to Bartonella henselae, B. elizabethae and B. quintana in Swedish domestic cats. Scand J Infect Dis. 2002;34(3):192-6. Inoue K, Kabeya H, Shiratori H, Ueda K, Kosoy MY, Chomel BB, Boulouis HJ, Maruyama S. Bartonella japonica sp. nov. and Bartonella silvatica sp. nov., isolated from Apodemus mice. Int J Syst Evol Microbiol. 2010;60(Pt 4):759-63. Inoue K, Maruyama S, Kabeya H, Hagiya K, Izumi Y, Une Y, Yoshikawa Y. Exotic small mammals as potential reservoirs of zoonotic Bartonella spp. Emerg Infect Dis. 2009;15(4):526-32. Jacomo V, Kelly PJ, Raoult D. Natural history of Bartonella infections (an exception to Koch’s postulate). Clin Diagn Lab Immunol. 2002;9:8-18. Jameson P, Greene C, Regnery R, Dryden M, Marks A, Brown J, Cooper J, Glaus B, Greene R. Prevalence of Bartonella henselae antibodies in pet cats throughout regions of North America. J Infect Dis. 1995;172(4):1145-9. Jeanclaude D, Godmer P, Leveiller D, Pouedras P, Fournier PE, Raoult D, Rolain JM. Bartonella alsatica endocarditis in a French patient in close contact with rabbits. Clin Microbiol Infect. 2009;15 Suppl 2:110-1. Johnson R, Ramos-Vara J, Vemulapalli R. Identification of Bartonella henselae in an aborted equine fetus.Vet Pathol. 2009;46(2):277-81. Jones SL, Maggi R, Shuler J, Alward A, Breitschwerdt EB. Detection of Bartonella henselae in the blood of 2 adult horses. J Vet Intern Med. 2008;22(2):495-8. Juvet F, Lappin MR, Brennan S, Mooney CT. Prevalence of selected infectious agents in cats in Ireland. J Feline Med Surg. 2010;12(6):476-82. Kaewmongkol G, Kaewmongkol S, Fleming PA, Adams PJ, Ryan U, Irwin PJ, Fenwick SG. Zoonotic Bartonella species in fleas and blood from red foxes in Australia. Vector Borne Zoonotic Dis. 2011;11(12):1549-53. Kaiser PO, Riess T, O'Rourke F, Linke D, Kempf VA. Bartonella spp.: throwing light on uncommon human infections. Int J Med Microbiol. 2011;301(1):7-15. Kamoi K, Yoshida T, Takase H, Yokota M, Kawaguchi T, Mochizuki M. Seroprevalence of Bartonella henselae in patients with uveitis and healthy individuals in Tokyo.Jpn J Ophthalmol. 2009;53(5):490-3. Kim YS, Seo KW, Lee JH, Choi EW, Lee HW, Hwang CY, Shin NS, Youn HJ, Youn HY. Prevalence of Bartonella henselae and Bartonella clarridgeiae in cats and dogs in Korea. J Vet Sci. 2009;10(1):85-7. Last Updated: July 2012 © 2012 Kosoy M, Bai Y, Lynch T, Kuzmin IV, Niezgoda M, Franka R, Agwanda B, Breiman RF, Rupprecht CE. Bartonella spp. in bats, Kenya. Emerg Infect Dis. 2010;16(12):1875-81. Kosoy M, Bai Y, Sheff K, Morway C, Baggett H, Maloney SA, Boonmar S, Bhengsri S, Dowell SF, Sitdhirasdr A, Lerdthusnee K, Richardson J, Peruski LF. Identification of Bartonella infections in febrile human patients from Thailand and their potential animal reservoirs. Am J Trop Med Hyg. 2010;82(6):1140-5. Kosoy M, Morway C, Sheff KW, Bai Y, Colborn J, Chalcraft L, Dowell SF, Peruski LF, Maloney SA, Baggett H, Sutthirattana S, Sidhirat A, Maruyama S, Kabeya H, Chomel BB, Kasten R, Popov V, Robinson J, Kruglov A, Petersen LR. Bartonella tamiae sp. nov., a newly recognized pathogen isolated from three human patients from Thailand. J Clin Microbiol. 2008;46(2):772-5. Kumasaka K, Arashima Y, Yanai M, Hosokawa N, Kawano K. Survey of veterinary professionals for antibodies to Bartonella henselae in Japan. Rinsho Byori. 2001;49(9):906-10. Lappin MR, Griffin B, Brunt J, Riley A, Burney D, Hawley J, Brewer MM, Jensen WA. Prevalence of Bartonella species, haemoplasma species, Ehrlichia species, Anaplasma phagocytophilum, and Neorickettsia risticii DNA in the blood of cats and their fleas in the United States. J Feline Med Surg 2006;8:85-90. Leibovitz K, Pearce L, Brewer M, Lappin MR. Bartonella species antibodies and DNA in cerebral spinal fluid of cats with central nervous system disease. J Feline Med Surg. 2008;10:332-7. Lin JW, Hsu YM, Chomel BB, Lin LK, Pei JC, Wu SH, Chang CC. Identification of novel Bartonella spp. in bats and evidence of Asian gray shrew as a new potential reservoir of Bartonella. Vet Microbiol. 2012;156(1-2):119-26. Lynch T, Iverson J, Kosoy M. Combining culture techniques for Bartonella: the best of both worlds. J Clin Microbiol. 2011;49(4):1363-8. Magalhães RF, Pitassi LH, Salvadego M, de Moraes AM, BarjasCastro ML, Velho PE. Bartonella henselae survives after the storage period of red blood cell units: is it transmissible by transfusion? Transfus Med. 2008;18(5):287-91. Maggi RG, Kosoy M, Mintzer M, Breitschwerdt EB. Isolation of candidatus Bartonella melophagi from human blood. Emerg Infect Dis. 2009;15(1):66-8. Maguiña C, Guerra H, Ventosilla P. Bartonellosis. Clin Dermatol. 2009;27(3):271-80. Maillard R, Grimard B, Chastant-Maillard S, Chomel B, Delcroix T, Gandoin C, Bouillin C, Halos L, Vayssier-Taussat M, Boulouis HJ. Effects of cow age and pregnancy on Bartonella infection in a herd of dairy cattle. Clin Microbiol. 2006;44(1):42-6. Maillard R, Petit E, Chomel B, Lacroux C, Schelcher F, VayssierTaussat M, Haddad N, Boulouis HJ. Endocarditis in cattle caused by Bartonella bovis. Emerg Infect Dis. 2007;13(9):1383-5. Márquez FJ. Molecular detection of Bartonella alsatica in European wild rabbits (Oryctolagus cuniculus) in Andalusia (Spain). Vector Borne Zoonotic Dis. 2010;10(8):731-4. page 18 of 20 Cat Scratch Disease Massei F, Messina F, Gori L, Macchia P, Maggiore G.High prevalence of antibodies to Bartonella henselae among Italian children without evidence of cat scratch disease. Clin Infect Dis. 2004;38(1):145-8. McGill S, Wesslén L, Hjelm E, Holmberg M, Auvinen MK, Berggren K, Grandin-Jarl B, Johnson U, Wikström S, Friman G. Bartonella spp. seroprevalence in healthy Swedish blood donors.Scand J Infect Dis. 2005;37(10):723-30. Morales SC, Breitschwerdt EB, Washabau RJ, Matise I, Maggi RG, Duncan AW. Detection of Bartonella henselae DNA in two dogs with pyogranulomatous lymphadenitis. J Am Vet Med Assoc. 2007;230(5):681-5. Mosbacher ME, Klotz S, Klotz J, Pinnas JL. Bartonella henselae and the potential for arthropod vector-borne transmission. Vector Borne Zoonotic Dis. 2011;11(5):471-7. Nakamura RK, Zimmerman SA, Lesser MB. Suspected Bartonella-associated myocarditis and supraventricular tachycardia in a cat. J Vet Cardiol. 2011;13(4):277-81. Namekata DY, Kasten RW, Boman DA, Straub MH, SipersteinCook L, Couvelaire K, Chomel BB. Oral shedding of Bartonella in cats: correlation with bacteremia and seropositivity. Vet Microbiol. 2010;146(3-4):371-5. Nervi SJ. Cat scratch disease. eMedcine.com; 2011 Nov. Available at: http://emedicine.medscape.com/article/214100overview. Accessed Jan 2012. Ohad DG, Morick D, Avidor B, Harrus S. Molecular detection of Bartonella henselae and Bartonella koehlerae from aortic valves of Boxer dogs with infective endocarditis. Vet Microbiol. 2010;141(1-2):182-5. Oliveira AM, Maggi RG, Woods CW, Breitschwerdt EB. Suspected needle stick transmission of Bartonella vinsonii subspecies berkhoffii to a veterinarian. J Vet Intern Med. 2010;24(5):1229-32. Oskouizadeh K, Zahraei-Salehi T, Aledavood S. Detection of Bartonella henselae in domestic cats' saliva. Iran J Microbiol. 2010;2(2):80-4. Palmero J, Pusterla N, Cherry NA, Kasten RW, Mapes S, Boulouis HJ, Breitschwerdt EB, Chomel BB. Experimental infection of horses with Bartonella henselae and Bartonella bovis. J Vet Intern Med. 2012;26(2):377-83. Pappalardo BL, Brown T, Gookin JL, Morrill CL, Breitschwerdt EB. Granulomatous disease associated with Bartonella infection in 2 dogs. J Vet Intern Med. 2000;14(1):37-42. Pappalardo BL, Correa MT, York CC, Peat CY, Breitschwerdt EB. Epidemiologic evaluation of the risk factors associated with exposure and seroreactivity to Bartonella vinsonii in dogs. Am J Vet Res. 1997;58:467–471. Pearce LK, Radecki SV, Brewer M, Lappin MR. Prevalence of Bartonella henselae antibodies in serum of cats with and without clinical signs of central nervous system disease. J Feline Med Surg. 2006;8(5):315-20. Pennisi MG, La Camera E, Giacobbe L, Orlandella BM, Lentini V, Zummo S, Fera MT. Molecular detection of Bartonella henselae and Bartonella clarridgeiae in clinical samples of pet cats from Southern Italy. Res Vet Sci. 2010;88(3):379-84. Perez C, Hummel JB, Keene BW, Maggi RG, Diniz PP, Breitschwerdt EB. Successful treatment of Bartonella henselae endocarditis in a cat. J Feline Med Surg. 2010;12(6):483-6. Last Updated: July 2012 © 2012 Pérez C, Maggi RG, Diniz PP, Breitschwerdt EB. Molecular and serological diagnosis of Bartonella infection in 61 dogs from the United States. J Vet Intern Med. 2011;25(4):805-10. Piérard-Franchimont C, Quatresooz P, Piérard GE. Skin diseases associated with Bartonella infection: facts and controversies. Clin Dermatol. 2010;28(5):483-8. Pons I, Sanfeliu I, Cardeñosa N, Nogueras MM, Font B, Segura F. Serological evidence of Bartonella henselae infection in healthy people in Catalonia, Spain. Epidemiol Infect. 2008;136(12):1712-6. Probert W, Louie JK, Tucker JR, Longoria R, Hogue R, Moler S, Graves M, Palmer HJ, Cassady J, Fritz CL. Meningitis due to a "Bartonella washoensis"-like human pathogen. J Clin Microbiol. 2009;47(7):2332-5. Psarros G, Riddell J 4th, Gandhi T, Kauffman CA, Cinti SK. Bartonella henselae infections in solid organ transplant recipients: report of 5 cases and review of the literature. Medicine (Baltimore). 2012;91(2):111-21. Public Health Agency of Canada. Pathogen Safety Data Sheet – Bartonella bacilliformis. Pathogen Regulation Directorate, Public Health Agency of Canada; 2011 Aug. Available at: http://www.phac-aspc.gc.ca/lab-bio/res/psds-ftss/bartonellabacilliformis-eng.php. Accessed 1 Jul 2012. Public Health Agency of Canada. Pathogen Safety Data Sheet – Bartonella henselae. Pathogen Regulation Directorate, Public Health Agency of Canada; 2011 Aug. Available at: http://www.phac-aspc.gc.ca/lab-bio/res/psds-ftss/bartonellahenselae-eng.php. Accessed 1 Jul 2012. Public Health Agency of Canada. Pathogen Safety Data Sheet – Bartonella quintana. Pathogen Regulation Directorate, Public Health Agency of Canada; 2011 Aug. Available at: http://www.phac-aspc.gc.ca/lab-bio/res/psds-ftss/bartonellaquintana-eng.php. Accessed 1 Jul 2012. Quimby JM, Elston T, Hawley J, Brewer M, Miller A, Lappin MR. Evaluation of the association of Bartonella species, feline herpesvirus 1, feline calicivirus, feline leukemia virus and feline immunodeficiency virus with chronic feline gingivostomatitis. J Feline Med Surg 2008;10:66–72. Regnery R, Tappero J. Unraveling mysteries associated with catscratch disease, bacillary angiomatosis, and related syndromes. Emerg Infect Dis. 1995;1:16-21. Reis C, Cote M, Le Rhun D, Lecuelle B, Levin ML, VayssierTaussat M, Bonnet SI. Vector competence of the tick Ixodes ricinus for transmission of Bartonella birtlesii. PLoS Negl Trop Dis. 2011;5(5):e1186. Rheault MN, van Burik JA, Mauer M, Ingulli E, Ferrieri P, Jessurun J, Chavers BM. Cat-scratch disease relapse in a kidney transplant recipient. Pediatr Transplant. 2007;11(1):105-9. Rolain JM, Boureau-Voultoury A, Raoult D. Serological evidence of Bartonella vinsonii lymphadenopathies in a child bitten by a dog. Clin Microbiol Infect. 2009;15 Suppl 2:122-3. Rolain JM, Rousset E, La Scola B, Duquesnel R, Raoult D. Bartonella schoenbuchensis isolated from the blood of a French cow. Ann N Y Acad Sci. 2003;990:236-8. Schaefer JD, Kasten RW, Coonan TJ, Clifford DL, Chomel BB. Isolation or detection of Bartonella vinsonii subspecies berkhoffii and Bartonella rochalimae in the endangered island foxes (Urocyon littoralis). Vet Microbiol. 2011;154(1-2):1359. page 19 of 20 Cat Scratch Disease Schaefer JD, Moore GM, Namekata MS, Kasten RW, Chomel BB. Seroepidemiology of Bartonella infection in gray foxes from Texas. Vector Borne Zoonotic Dis. 2012;12(5):428-30. Schwartz RA. Dermatologic manifestations of bacillary angiomatosis. eMedicine.com; 2012 Feb. Available at: http://emedicine.medscape.com/article/1051846-overview. Accessed 12 Jul 2012. Solano-Gallego L, Bradley J, Hegarty B, Sigmon B, Breitschwerdt E. Bartonella henselae IgG antibodies are prevalent in dogs from southeastern USA. Vet Res. 2004;35:585–595 Stiles J. Bartonellosis in cats: a role in uveitis? Vet Ophthalmol. 2011;14 Suppl 1:9-14. Stojanovic V, Foley P. Infectious disease prevalence in a feral cat population on Prince Edward Island, Canada. Can Vet J. 2011;52(9):979-82. Sykes JE, Westropp JL, Kasten RW, Chomel BB. Association between Bartonella species infection and disease in pet cats as determined using serology and culture. J Feline Med Surg. 2010;12(8):631-6. Tea A, Alexiou-Daniel S, Arvanitidou M, Diza E, Antoniadis A. Occurrence of Bartonella henselae and Bartonella quintana in a healthy Greek population. Am J Trop Med Hyg. 2003;68(5):554-6. Telford SR 3rd, Wormser GP. Bartonella spp. transmission by ticks not established. Emerg Infect Dis. 2010;16(3):379-84. Tsai YL, Chomel BB, Chang CC, Kass PH, Conrad PA, Chuang ST. Bartonella and Babesia infections in cattle and their ticks in Taiwan. Comp Immunol Microbiol Infect Dis. 2011;34(2):179-87. Van der Heyden TR, Yong SL, Breitschwerdt EB, Maggi RG, Mihalik AR, Parada JP, Fimmel CJ. Granulomatous hepatitis due to Bartonella henselae infection in an immunocompetent patient. BMC Infect Dis. 2012;12:17. Varanat M, Broadhurst J, Linder KE, Maggi RG, Breitschwerdt EB. Identification of Bartonella henselae in 2 cats with pyogranulomatous myocarditis and diaphragmatic myositis. Vet Pathol. 2012;49(4):608-11. Vayssier-Taussat M, Le Rhun D, Bonnet S, Cotté V. Insights in Bartonella host specificity. Ann N Y Acad Sci. 2009;1166:127-32. Vermeulen MJ, Herremans M, Verbakel H, Bergmans AM, Roord JJ, van Dijken PJ, Peeters MF. Serological testing for Bartonella henselae infections in The Netherlands: clinical evaluation of immunofluorescence assay and ELISA. Clin Microbiol Infect. 2007;13(6):627-34. Welch DF, Carroll KC, Hofmeister EK, Persing DH, Robison DA, Steigerwalt AG, Brenner DJ. Isolation of a new subspecies, Bartonella vinsonii subsp. arupensis, from a cattle rancher: identity with isolates found in conjunction with Borrelia burgdorferi and Babesia microti among naturally infected mice. J Clin Microbiol. 1999;37(8):2598-601. Yager JA, Best SJ, Maggi RG, Varanat M, Znajda N, Breitschwerdt EB. Bacillary angiomatosis in an immunosuppressed dog. Vet Dermatol. 2010;21(4):420-8. Yamamoto, K, Chomel BB, Kasten RW, Hew CM, Weber DK, Lee WI. Experimental infection of specific pathogen free (SPF) cats with two different strains of Bartonella henselae type I: A comparative study Vet Res. 2002;33:669 –684. Last Updated: July 2012 © 2012 Zarraga M, Rosen L, Herschthal D. Bacillary angiomatosis in an immunocompetent child: a case report and review of the literature. Am J Dermatopathol. 2011;33(5):513-5. *Link defunct as of July 2012 page 20 of 20