Urinary Tract Infections How to diagnose and when to treat:

Urinary Tract Infections
How to diagnose and when to treat:
Evidence based answers for the
primary care physician
KRIST IN N IEREN BERG, M D
S W E D I S H FA M I LY M E D I C I N E R E S I D E N C Y – F I R S T H I L L
R 3 TA L K S : M AY 9 , 2 0 1 4
Declarations
 None.
Objectives
 Review the epidemiology of UTIs
 Define how to properly diagnose cystitis ,




pyelonephritis, and asymptomatic bacteriuria
Review the evidence behind antibiotic treatment
Overview of care of the pregnant woman
What to do about recurrent UTI
Further areas of investigation
Definitions
 Uncomplicated UTI: acute cystitis or pyelonephritis occurring in
healthy premenopausal, nonpregnant women with no history of
abnormal urinary tract
 Complicated UTI: infections in patients with functional,
metabolic, or anatomical conditions that may increase risk of infection
or treatment failure / serious outcomes
 Acute Cystitis: Infection of the urinary bladder (lower urinary
tract)
 Acute pyelonephritis: infection of the kidney (upper urinary
tract)
Epidemiology
 UTI: Most commonly occurring bacterial
infection in the outpatient setting. ~50% of women
by age 30
 Estimated incidence 10-15%
 average of 6 days of discomfort, leading to ~ 7
million outpatient visits / year, estimated costs >
$1.5 billion!
 Risk factors: Sexual intercourse, spermicide, new
sexual partner in past year, previous UTI, family hx
of UTI
Pathogenesis
 Colonization of vaginal introitus by uropathogens
from fecal flora > ascension via urethra to bladder
 Pyelonephritis: occurs when pathogen ascends to
kidneys via ureters
 E. Coli causes 75-95% of all uncomplicated UTI
Acute Cystitis: Diagnosis
 History: New onset of frequency and dysuria, with
absence of vaginal discharge or irritation: PPV 90%
 Physical exam: usually normal. 10-20%
suprapubic tenderness.
 Labs: urine dip vs. urinalysis with urine
microscopy.



Nitrites and LE most accurate indicators of acute
uncomplicated cystitis in symptomatic women
Culture recommended only if suspected pyelo, recurrence,
atypical symptoms, or complicated infection
Colony count of > 103 CFU / mL is diagnostic > other studies
showing use of 102 in women with classic symptoms.
Urine Dip: what’s that again?
 Leukocyte Esterase: indicates presence of
bacteria. Sensitivity up to 96%, specificity up to 87%
 Nitrite: Found in nitrate reducing bacteria: fairly
good at detecting enterobacteriaceae. Not as
sensitive, but very specific (up to 98%)
Microbiology
 Main cause is E.Coli (75-95%)
 Other enterobacteriaceae (proteus, klebsiella) or Staph




saprophyticus.
Contaminants include lactobacilli, enterococci, GBS, or
coag neg staph
Resistance rates > 20% common for ampicillin
Fluoroquinolone resistance generally < 10% but
increasing over past decade
Use of TMP-SMX in past 3-6 months or international
travel: independent risk factors for bacteria resistance,
concern if > 20%
Diagnosis of Pyelonephritis
 History: variable with similar symptoms of cystitis
but may additionally have fever, chills, flank pain,
N/V
 Physical exam: Fever, tachycardia, CVAT (any
signs of sepsis)
 Labs: Urinalysis and Urine culture


Urine culture > 104 cfu/mL indicates clinically relevant
bacteriuria
Imaging not needed generally if clinical response within 72
hours.
Treatment of Pyelonephritis
 OUTPATIENT tx: Ok for those with mild to moderate illness who
can be stabilized with rehydration, and follow up with close supervision.
Ciprofloxacin: 500mg BID x 7 days
Ciprofloxacin 1000mg ER x 7 days or
Levofloxacin 750mg x 5 days
Trimethoprim-sulfamethoxazole DS BID x 14D
 INPATIENT tx: severe illness, high fever, pain, inability to hydrate
or take oral meds, pregnancy, or concern about compliance.

- initial IV abx (fluoroquinolone, aminoglycoside, extended spectrum cephalosporin or
penicillin, or carbapenem. Regimen tailored to susceptibility results.
 Treatment response within 48 hours
Self-diagnosis and telephone management
 Studies indicate that if a woman has 2 symptoms of
UTI, without vaginal discharge or irritation she has >
90% chance of having UTI
 Numerous studies have looked at treatment of UTI
over the phone.
 Randomized trial in 2001: similar symptoms and
patient satisfaction
 Retrospective cohort study of > 4,000 women
showed that it was safe to treat as outpatient but up
to 20% women require office evaluation within 6
weeks.
Outcomes of telephone based treatment
UTI in men
UTI in men
 Usually considered complicated because majority occur
in infants or elderly associated with urologic
abnormalities
 Small number occur in men age 15-50. (5-8 / 100,000
men per year)
 Labs: Recommended UA and culture.

104 CFU/ml is diagnostic.
 Men with recurrent UTI > undergo evaluation for
prostatitis
 Treatment:


TMP-SMX BID, Cipro BID / daily, Levo daily. (7-14 days)
Do not use nitrofurantoin or beta-lactams due to poor tissue
concentrations > less effective for occult prostatitis.
Asymptomatic Bacteriuria
 Diagnosis
 >105 CFU/mL in asymptomatic women collected in 2
consecutive voided specimens
 1 clean catch needed for men
 Single catheterized specimen > 102 for men or women.
 Screening: in pregnant women (more to follow),
before urologic procedures
 Treatment: 3-7 days.
 Prevalence: 2-7% in healthy young pregnant or nonpregnant women.
What to do in Pregnancy?
Asymptomatic bacteriuria in pregnancy
 Increases risk of complications:
 20-30x increased risk of pyelonephritis
 More likely for premature delivery and low birth weight
 Screen: at least once in early pregnancy > treated if positive.
 Periodic screening after therapy (per ACOG 3rd trimester)
 No recommendation for screening for culture-negative women in later pregnancy
(consider in high risk women)
 Treatment:
 Decreases risk of pyelo from 20-35% > 1-4%
 No determined duration of treatment (3-7 days)
 Fluoroquinolones contraindicated
 TMP-SMX: avoid during 1st trimester > category C
 Nitrofurantoin: 100mg BID x 5 days > category B (50-100mg qhs > suppression)
 Amoxicillin: 500mg BID 3-7 days > category B
 Augmentin: 500mg BID 3-7 days > category B
 Cephalexin: 500mg BID 3-7 days. > category B
 Test of cure
Cystitis in pregnancy
 Diagnosis: Should perform urine culture
 103 CFU/mL
 Treatment:
 Nitrofurantoin 100mg BID x 5 days
 Cefpodoxime 100mg BID x 3-7 days
 Augmentin 500mg BID x 3-7 days
 Fosfomycin 3g x 1
 TMP-SMX DS BID x 3 days (avoid in 1st trimester or term)
 Amoxicillin 500mg BID x 7 days
 Suppressive therapy: bacteria persists after 2 or more courses, or
for recurrent infection


Nitrofurantoin 50-100mg qhs
Cephalexin 250-500mg qhs
 GBS: treated as GBS carriers and receive prophylactic abx during
labor.
Pyelonephritis in pregnancy
 Pathogenesis:

Pressure on bladder, smooth muscle relaxation, immunosuppression
of pregnancy, increased plasma volume
 Treatment:





Hospitalization and IV abx until afebrile x 48 hours
3rd generation cephalosporins favored over 1st /2nd gen
Avoid aminoglycosides due to ototoxicity
Carbapenems > effective vs ESBL
Complete 10-14 days tx
 Recurrence:



Occurs in 6-8% or women > treat with prophylaxis
Nitrofurantoin 50-100mg qhs
Cephalexin 250-500mg qhs
Recurrent UTI
Recurrent UTI: Symptomatic UTI that follows resolution of an
earlier episode, usually after appropriate treatment
Relapse: Symptomatic recurrent UTI with the same organism <
2 weeks after treatment.
Reinfection: Either recurrent UTI with previously isolated
bacteria with a negative intervening culture, OR a recurrent UTI
caused by a 2nd bacterial isolate. > 2 weeks after treatment.
*Most are due to REINFECTION with same organism.
 Epidemiology: In college women > 25% will have recurrence within
6 months, ~ 3% will have > 1 recurrence. In all women: ~35-50%
recurrence within 1 year.
 Diagnosis: Obtain urine culture
Recurrent UTI
 Treatment: same as for regular UTI > consider test of cure
 Prophylaxis: consider if 2UTIs in 6 months or 3 in 1 year.
6-12 mo tx will reduce rate of relapse.
 Postcoital prophylaxis results in less abx use.
 Cranberry juice / probiotics: Lacking randomized trials.
Recurrent UTI
What are the bugs at Swedish?
Effect of stewardship intervention on adherence to UTI
/ pyelo guidelines in ED setting
 ED chose to use UTI orderset as a quality indicator
 Feedback given to ED doc by ID and stewardship
 Primary outcome > adherence to IDSA guideline
 Secondary outcome > total days of abx, fluoroquinolones for
cycsitis, diagnositic accuracy.
Outcomes of stewardship interventions
 Improved adherence to guidelines with minimal resources
 Decreased unnecessary days of abx use
 Reduced overuse of fluoroquinolones
 No change in UTI diagnostic accuracy
Swedish ED smartset… not so smart?
 Labs: not possible to obtain UA without culture if
indicated, blood culture available, but no PCT

No wet mount, GC/CT
 Treatment: amoxicillin, cefpodoxime, azithro, doxy,
erythro, levo, nitrofurantoin, phenazopyridine,
bactrim (no specification re: duration)
 No delineation of complicated vs. uncomplicated,
cystitis vs. pyelonephritis
 Appropriate inpatient supplemental orders
Take Home Points
 Cephalosporins are NOT first line for UTI treatment
 Beware of Bactrim resistance > 20%
 Reserve use of fluoroquinolones in cystitis
 If resistance pattern unknown in pyelo > good to
treat with 1 dose CTX
 Antibiotic stewardships and ordersets > could be
helpful in helping to follow treatment guidelines.
 Treating over the phone may not cause harm to
patient, but could worsen collateral damage!
References
1.
Gupta K, Hooton T, et al. International Clinical Practice Guidelines for the Treatment of Acute Uncomplicated
Cystitis and Pyelonephritis in Women: A 2010 Update by the Infectious Diseases Society of America and the
European Society for Microbiology and Infectious Diseases. Clinical Infectious Diseases. 2011;52(5):103-120.
2. Coglan R and Williams M. Diagnosis and Treatment of Acute Uncomplicated Cystitis. American Family Physician.
2011;84(7):771-776.
3. Schauberger C, Merkitch K, et al. Acute Cystitis in Women: Experience with a Telephone-Based Algorithm.
Wisconsin Medical Journal. 2007;106(6):326-330.
4. Barry HC, Hickner J, et al. A rnadomized control trial of telephone management of suspected urinary tract
infection in women. Journal of Family Practice. 2001;50(7):589-594.
5. Vinson D and Queensberry C. The Safety of Telephone Management of presumed cystitis in women. Arch Intern
Med. 2004;164(9):1026-1029.
6. Nicolle L, Bradley S, et al. Infectious Diseases Society of America Guidelines for Diagnosis and Treatment of
Asymptomatic Bacteriuria in Adults. Clinical Infectious Diseases. 2005;40:643-654.
7. Kodner C and Gubton E. Recurrent Urinary Tract Infections in Women: Diagnosis and Management. American
Family Physician. 2010;82(6)638-643.
References Cont’d
8. Delzell J and Lefevre M. Urinary Tract Infections During Pregnancy. American Family Physician. 2000;61(3):713-720
9. Hooton T, Bradley S, et all. Diagnosis, Prevention, and Treatment of Catheter-Associated Urinary Tract Infection in Adults:
2009 International Clinical Practice Guidelines from the Infectious Diseases Society of America. Clinical Infectious
Diseases. 2010;50:625-663.
10. Bilir F, Akdemir N, et al. Increased serum procalcitonin levels in pregnant patients with asymptomatic bacteriuria. Annals
of Clinical Microbiology and Antimicrobials. 2013;12:25-30.
11. Ha Y, Kang C, Wi Y, et al. Diagnostic usefulness of procalcitonin as a marker of bacteremia in patients with acute
pyelonephritis. Scandinavian Journal of Clinical and Laboratory Investigation. 2013; 1-5
12. 12. Sugimoto K, Adomi S, et al. Procalcitonin as an indicator of urosepsis. Research and Reports in Urology. 2013:5
77-80.
13. 13. Park J, Wee J, et all. Serum procalcitonin level for the predication of severity in women with acute pyelonephritis in
the ED: value of procalcitonin in acute pyelonephritis. The American Journal of Emergency Medicine. 2013;31:10921097.
14. 14. Hecker M, Fox C. et al. Effect of a Stewardship Invervention on Adherence to Uncomplicated Cystitis and
Pyelonephritis Guidelines in an Emergency Department Setting. Plos One. 2014;9(2):1-8.