Determination of Antimicrobial Resistance Pattern and Production of Extended-Spectrum Β-Lactamases amongst Escherichia coli and Klebsiella pneumoniae from Clinical Isolates

Background: the prevalence of antibiotic resistance among extendedspectrum β-lactamase (esbl) producing escherichia coli and klebsiella pneumoniae has been increased markedly in recent years. the present study was done to know the prevalence of esbl production among isolates of e. coli and k. pneumoniae and to study the susceptibility pattern of isolates against different antibiotics. methods: extended-spectrum β-lactamase producing e. coli and k. pneumoniae were isolated from various samples obtained from outdoor and indoor patients of the prathima institute of medical sciences, andhra pradesh, india. they were tested for esbl production by double disc synergy test and resistance to various antibiotics like fluoroquinolones, cephalosporins, aminoglycosides and ß-lactamase inhibitor combinations and susceptibility to carbapenems were determined by kirby-bauer disc diffusion method. results: a total of 94 esbl producing isolates were obtained. of them 60 were e. coli and 34 k. pneumoniae. they were obtained from urine, sputum, pus, wound swabs blood & tracheal aspirates. urine (38.29%) was the main source of esbl-producing isolates from all patients, followed by sputum (34.04%). about 37.23% of these isolates were collected from medical wards and 27.65% were collected from outdoor. all isolates were susceptible to imipenem. the resistance to cephalosporins (1-4 generations) was almost 100%. resistance to aztreonam, ampicillin and co-amoxyclav was also 100%. a high degree of resistance was observed to other antibiotics. conclusion: the highest prevalence of resistance to esbl in e. coli and k. pneumonia is associated with a multitude of infections in hospitalized patients with a significant longer duration of hospital stay, increased morbidity and greater hospital charges. advanced drug resistance surveillance and molecular characteristics of esbl isolates is necessary to guide the proper and judicious antibiotic use.