Extended spectrum beta-lactamase producing multidrug resistant urinary isolates from children visiting Kathmandu Model Hospital.

A study was conducted to analyze the status of the multidrug resistant (MDR) isolates producing Extended Spectrum of beta-lactamase (ESBL) among the uropathogens infecting children less than 15 years from November 2010 to April 2011 in the Bacteriology laboratory, Kathmandu Model Hospital. Urine samples received in the laboratory were processed for routine culture. The antimicrobial susceptibility of bacterial isolates was determined following Clinical and Laboratory Standard Institute (CLSI) recommended Kirby-Bauer Disc Diffusion method. The defining criterion in this study for an isolate to be multidrug resistant was resistance to two or more drugs of different structural classes. Isolates were confirmed for ESBL-production by performing the Inhibitor Potentiated Disk Diffusion (IPDD) Test/ Combined Disk Assay for ESBL confirmation. Out of 252 urine samples received in the laboratory, 59(23.41%) showed significant growth of which 54.23% (32/59) were MDR isolates. Additionally, 25 isolates (21 Escherichia coli and 3 Citrobacter freundii and single Enterobacter aerogenes) among them were ESBL producers. Among the first line drugs used against gram negative isolates, Nitrofurantoin was drug of choice; meanwhile among the second line drugs Cefoperazone/Sulbactum was drug of choice, whereas, Cephotaxime, Ciprofloxacin, Norfloxacin and Gentamicin were the drug of choice for Gram positive isolates. Significant association was found between ESBL production and spectrum of drug resistance (p < 0.05).