Extended Spectrum β-Lactamases among Gram-negative bacteria from an Egyptian pediatric hospital: a two-year experience

Abstract

Background Knowledge of the anti-microbial susceptibility pattern of common pathogens in a given area helps to inform the choice of empirical antibiotic therapy. The aim of this study was to determine the existence and to describe the characteristics of extended spectrum β-lactamase (ESBLs) in a pediatric hospital in Mansoura University, Egypt, to aid in the choice of empirical antibiotic therapy. Method: Between January 2005 and December 2006, blood samples were collected from children suspected to have nosocomial infections in a pediatric hospital in Mansoura. The gram negative isolates were identified, tested for antimicrobial susceptibility and analyzed for presence of ESBL. Results: A total of 1,600 children with suspected septicemia were studied. Gram negative septicemia was identified in 816 cases (45%). The commonest isolated gram negative bacilli was Klebsiella species (38.2%) followed by Enterobacter species (32.4), Serratia species (16.2%) and Burkholderia cepacia (10.3%). The highest susceptibility was for imipenem (74.3%) followed by gentamicin (70.8%), cefoperazone (64.5%) and cefotaxime (63.2%). The highest resistant rate was for cefazolin and ampicillin/sulbactam (75.5% for each), followed by cefuroxime 70.3% and ceftriaxone (63.5%). The ESBL was found in 44.5% for cefotaxime and 50% for ceftazidime by double discs method. Conclusion: This study highlights the emergence of antibiotic resistant gram negative bacilli in a pediatric hospital with special emphasis on extended β-lactamase resistant strains. Our results show that the most appropriate antibiotics to be used for empirical therapy are amikacin and gentamicin.