Journal of Clinical and Diagnostic Research (Apr 2012)
Prevalence of Extended Spectrum Beta Lactamase (ESBL) Producers among Gram Negative Bacilli from Various Clinical Isolates in a Tertiary Care Hospital at Jhalawar, Rajasthan, India
Abstract
Background and Objectives: The resistance to broad spectrum β-lactams which is mediated by the extended spectrum beta lactamase (ESBL) enzyme is an increasing problem now-a-days. This resistance mechanism has been responsible for nosocomial outbreaks, serious therapeutic failure if it is not detected on time and the outbreak of multidrug resistant, gram negative pathogens that need expensive control measures. As no data was available on the prevalence of ESBL in this region, the current study was undertaken to determine the prevalence of the ESBL producing strains in our hospital based population of Jhalawar. Aim: To know the prevalence of ESBL producing organisms at our tertiary care hospital at Jhalawar. Material and Methods: A total of 219 consecutive, nonrepetitive, gram negative isolates, which were resistant to one of the third generation cephalosporins (cefotaxime, ceftriaxone or ceftazidime) were selected as “Suspicious for ESBL production” as recommended by the Clinical and Laboratory Standards Institute (CLSI). These isolates were confirmed for ESBL production by the double disc synergy test (DDST) and the phenotypic confirmatory disc diffusion test (PCDDT) and they were further confirmed by the E-test ESBL strip randomly. Result: Out of the 219 isolates which were tested, 135 (61.6%) were found to be ESBL producers by PCDDT and 126 (57.5%) were found to be ESBL producers by DDST. Twenty-eight randomly selected isolates were further confirmed by the E-test ESBL strip, which showed a highly significant correlation with PCDDT (p value <0.001). The isolates of Escherichia coli (73.5%) were the most common ESBL producers, followed by Proteus vulgaris (60%), K. pneumoniae (58.1%) and others. The maximum ESBL production was seen in urine (66.4%), followed by pus (57.3%) and others (54.2%). Imipenem (98.5%), piperacillin/ tazobactum (72.6%) and amikacin (64.5%), in the decreasing order, were the most active and reliable agents for the treatment of the infections which were caused by the ESBL producing organisms. Conclusion: There is a high prevalence of ESBL production in our hospital and so, it is essential to report the ESBL production along with the routine sensitivity reports, which will help the clinician in prescribing proper antibiotics. Also, control measures which include the judicious use of antibiotics, antibiotic cycling, the implementation of appropriate infection control measures and the formulation of an antibiotic policy must be done, to prevent the spread of these strains.
