Profile in Pan European Networks Science & Technology â Issue 14
Transcription
Profile in Pan European Networks Science & Technology â Issue 14
PROFILE INFECTIOUS DISEASES A NEED FOR GLOBAL ACTIONS Alongside appropriate antibiotic usage, rapid diagnosis of multidrug-resistant bacteria may limit their spread and save lives, explains Youri Glupczynski, professor of clinical microbiology at the Université catholique de Louvain ntibiotics are one of the most important therapeutic discoveries in medical history. They have revolutionised the treatment of patients with bacterial infections and have contributed to reducing the mortality and morbidity of bacterial diseases. Unfortunately, antibiotics have been liable to misuse, and they are often unnecessarily prescribed for viral infections against which they have no effect. Similarly, when diagnoses are not accurately made, which too often still occurs in current medical practice, broad-spectrum antibiotics (i.e. antibiotics that kill a large proportion of various bacteria and not only the bacteria responsible for the disease) are prescribed because the causative micro-organism is not known. Misuse of antibiotics leads to the emergence and selection of resistant bacteria. It has become the reality that doctors in Europe and worldwide sometimes now face situations where infected patients cannot be treated adequately because the bacterium responsible is totally resistant to available antibiotics. A Youri Glupczynski, professor of clinical microbiology at the Université catholique de Louvain, heads the National Reference Centre in Belgium for the surveillance of multi-resistant Gramnegative organisms (Enterobacteriaceae, Pseudomonas and Acinetobacter spp). In the following, he outlines the aims of his current research into tackling multidrug-resistant bacteria (MDRB) and his hopes for the future. Focus of interests The main field of our laboratory research focuses on the development and validation of novel diagnostic tools for the rapid diagnosis of MDRB, mostly carbapenemase-producing Enterobacteriaceae (CPE). The Enterobacteriaceae compose part of the commensal human gut flora and are often the cause of community and healthcare-associated infections. Klebsiella pneumoniae and Escherichia coli are two bacteria that belong to the Enterobacteriaceae family. Klebsiella pneumoniae is a common cause of Gram-negative urinary, respiratory tract and bloodstream infections. Escherichia coli is the most frequent cause of bloodstream, community and hospital-acquired urinary tract infections reported worldwide and one of the most common global food-borne pathogens. Treatment of infections due to CPE has become more challenging since a large percentage of these bacteria have become resistant to many and sometimes all antibiotics to which they were once susceptible. CPE have increasingly spread in Europe over recent years. In 2013, only a minority of countries in the EU reported no cases of CPE, and 146 Pan European Networks: Science & Technology 14 Youri Glupczynski several others that had only reported sporadic occurrences of CPE in 2010 were witnessing regional or inter-regional spread, or even an endemic situation. Classically, the detection of MDRB from clinical or screening specimens from patients may take up to three to four days by conventional microbiological methods, which may be too long to wait before providing appropriate treatment to patients with severe infection and which may also lead to secondary crosstransmission of these bacteria to other persons (mostly through healthcare personnel during nursing activities because of inadequate hand hygiene practice). The second main focus of research is to provide novel understanding of the epidemiology (i.e. the reservoirs and modes of transmissions of MDRB) and to gain insights into the patient’s individual risk factors and the dynamic of diffusion of these organisms in different human health sectors (hospitals, long term facility care and the primary care level in the community). The implementation of an integrated surveillance laboratory network (including both hospital and private laboratories) coupled with the development of early warning systems aims to implement welladapted strategies (barrier precautions, good hand hygiene practice) for prevention of cross-transmission of CPE within and between the different human healthcare sectors. Most important advances In close collaboration with the Public Health Institute, the laboratory has been able to organise a structured active surveillance of MDRB in Belgium since 2010. Since antimicrobial resistance is a global issue, our current programme focuses on the situation not only in hospitals but also in nursing homes. My laboratory co-ordinated a multicentric survey carried out in 2011 (to be repeated in May 2015) to assess the prevalence and the www.paneuropeannetworks.com PROFILE INFECTIOUS DISEASES laboratories. In collaboration with an industrial partner (CorisBio Concept), the group developed an immunochromatographic test (lateral-flow assay) for rapid identification of OXA-48 and KPC carbapenemase-producing organisms using monoclonal antibodies targeting specific regions of the carbapenemase proteins (OXA-48 and KPC K-SeT). In combination with the BYG electrochemical sense screening, this immunochromatographic assay will render possible the precise identification of CPE isolates from culture colonies in less than one hour. Clinical validation of these two assays is currently on-going in the setting of a multicentric survey with reference laboratories in several countries (France, UK, Germany, Spain and Greece). Rapid diagnosis of infection caused by MDRB may improve patient management and save lives risk factors of asymptomatic carriage of MDRB in 3,000 residents from 60 nursing homes in Belgium. This study showed that low functional status of residents (i.e. lack of independency for practising common activities of daily life) and exposure to antibiotics (within the last three months) were strong predictors for colonisation by MDRB (especially Enterobacteriaceae). Microbiological characterisation also showed close relatedness between MDRB found in nursing home residents and in hospitalised patients, suggesting cross-transmission and hence emphasising the need for global co-ordination of the surveillance of MDRB within and between nursing homes and hospitals. The implementation of a large network including more than 100 laboratories (out of a total of 140) also allowed for improvement of diagnostic practices through education activities (organisation of external quality assessments, education workshops, and onsite training sessions). A collaborative network could also successfully be implemented with healthcare providers on the field, and this has proved very useful to standardising practices at the local and regional level. Our group’s final ambition is to create and develop simple diagnostic tests that may speed up the identification of MDRB. We believe that early accurate laboratory diagnoses may prove useful for better patient management (in improving antibiotic usage) and may ultimately save lives. Hope for the future The global expansion of MDRB is a multifaceted problem which will require vast and versatile solutions. Tackling the burden of antimicrobial resistance will require comprehensive interventions involving a wide range of sectors of society: policy makers, healthcare, education, industry, environmental agencies, veterinary medicine, research and other areas. While the new EU framework programme has placed emphasis on supporting research and innovation in health, the area of prevention is not at the top of the agenda in most countries where it remains insufficiently funded. A co-ordinated effort should be made in order to reduce inequalities between healthcare systems in Europe, and alongside innovative laboratory diagnostic tests and the development of antibiotics with new mechanisms of action, emphasis should be put more on surveillance system design and guidance on infection prevention and control measures for MDRB – research areas that are clearly underfunded. Current developments Our research group is currently involved in the development of several new diagnostic tools aiming at the rapid and specific detection of CPE using innovative approaches. One such assay (BYG test) uses electrochemical sense technology (electrochemical portable USB station and activated disposable miniature electrodes counting eight electrochemical cells). This assay allows for the detection of carbapenem hydrolysis and is able to detect all different types of CPE isolates from culture colonies within 30 minutes. This simple technology is prone to multiplexing, hence potentially allowing the development of a novel rapid antimicrobial susceptibility method in the laboratory (in vitro assessment of susceptibility to antibiotics by conventional methods takes 18-24 hours). The identification of the exact type of carbapenemases (which may be needed for epidemiology purposes) is mostly based on molecular techniques targeting specific DNA sequences present in the bacteria (carbapenemaseencoding genes). These tests are expensive and necessitate skilled personnel ,hence limiting their use to only a small number of Youri Glupczynski, MD, PhD Professor of Clinical Microbiology, Université Catholique de Louvain Head of National Reference Laboratory for Antimicrobial Resistance CHU Dinant Godinne UCL tel: +32 81423245 [email protected] [email protected] http://www.uclouvain.be/ https://nrchm.wiv-isp.be/fr/default.aspx http://www.nsih.be/surv_carba/carbapenemase_fr.asp Reproduced by kind permission of Pan European Networks Ltd, www.paneuropeannetworks.com © Pan European Networks 2015 www.paneuropeannetworks.com Pan European Networks: Science & Technology 14 147