|EDITORIAL ON SPECIAL ARTICLE
|Year : 2022 | Volume
| Issue : 2 | Page : 53-54
Carbapenem resistance testing – A challenge in India
Ranganathan N Iyer
Department of Clinical Microbiology Infections and Infection Control, Gleneagles Global Hospitals, Hyderabad, Telangana, India
|Date of Submission||26-Nov-2022|
|Date of Decision||28-Nov-2022|
|Date of Acceptance||30-Nov-2022|
|Date of Web Publication||13-Dec-2022|
Ranganathan N Iyer
Gleneagles Global Hospitals, Near District Collector's Office Lakdi Ka Pul, Hyderabad - 500 004, Telangana
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Iyer RN. Carbapenem resistance testing – A challenge in India. J Acad Clin Microbiol 2022;24:53-4
Carbapenemase-producing Enterobacterales have emerged as the most dangerous pathogens causing invasive infections, particularly bloodstream infections in immunosuppressed patients. These organisms have the ability to produce a range of serine and metallo-beta-lactamase enzymes coded for by genes. These have helped the organisms evade the immune mechanisms of the host and have led to increased morbidity and mortality. A few agents such as Tigecycline, Colistin and Fosfomycin have been tried either alone or in combination for the management of these recalcitrant infections with variable success. This is because there has been documented resistance to all these agents in recent times that limit their use.,
Conventional susceptibility testing has only conferred marginal benefit in the management of patients infected with these pathogens. This is particularly so when there is a coproduction of multiple resistance enzymes and the interaction of many resistance mechanisms. Hence, the detection of the resistance genes that confer the ability to elaborate carbapenemase enzymes has become important in directing both the laboratory and the clinical departments towards appropriate rescue antimicrobial therapy of these patients.
Clinical microbiology practice in India differs from one part of the country to another, based on the patient number served by the laboratory and facilities for extended and rapid diagnostic testing available with the laboratory to name a few variables. The detection of carbapenemases, thus, varies from one laboratory to another. This impacts the surveillance data gathered from different parts of the country which lack uniformity and are not consistent. India has a range of clinical microbiology laboratory facilities from state government-run hospital-based laboratories, to hospital-based as well as stand-alone laboratories in the private sector. These laboratories understandably would have different capabilities for the detection of mechanisms of antimicrobial resistance in infectious pathogens. In addition, many laboratories are not accredited for such testing facilities and do not exercise internal quality control.
In the present study conducted by Raja et al., a serious attempt was made to gather data on the prevalence of carbapenemases in clinical practice, and the way these enzymes are detected by clinical laboratories, all of which impact patient care. Questionnaires prepared and sent across to many laboratories across the country were met with a response from 20 laboratories, predominantly in South India. It was surprising and disturbing to note that the testing for susceptibility to carbapenems is not uniform in the country. Many laboratories resorted to testing either Imipenem or Meropenem susceptibility, with fewer laboratories demonstrating an ability to test Ertapenem, Imipenem and Meropenem. The study observed this variation despite all the participating centres being hospital-based clinical microbiology laboratories, out of working hours microbiology service was available in only 16 centres out of the 20 included in the study. It is a challenge if not an impossibility to elucidate resistance mechanisms such as AmpC with an overactive efflux pump or deficient porin channels when all the carbapenems are not tested in clinical laboratories. Despite coming in the second position after Enterobacterales, Acinetobacter baumannii posed a major problem in almost all hospitals with a number of isolates elaborating carbapenemases. Genotypic data and analysis were available from three centres and the major genotype detected were NDM, OXA-48 and even KPC, although this is an unusual finding in India. Urine followed by respiratory tract specimens was the major source of these pathogens.
The implementation of an antimicrobial policy was evidenced in most of the centres participating in the study barring three centres that appear to have specific rather than general overall antibiotic policies tailored to specific requirements in these hospitals. A robust antibiotic policy with implementation may be possible only when equally robust data on the prevalence of carbapenem resistance and carbapenemase gene detection are available.
Carbapenem-resistant organisms have become endemic in India and the facilities for testing, detection and elucidation of resistance mechanisms are vital for a strong antimicrobial stewardship and infection prevention programme in all hospitals across the country. It is equally important for a uniform range of agents to be tested in clinical laboratories across the country. Greater emphasis may be required in the future on the mechanisms of resistance in A. baumanii and the management of the same. It is a fervent hope that this uniform testing reporting of all aspects of carbapenem resistance would pave the way for better management of recalcitrant infections in the future.
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