Prevalence of extended-spectrum β-lactamase-producing Gram-negative bacteria in septicaemic neonates in a tertiary care hospital

The present study was undertaken to investigate the high incidence of multiresistant Gram-negative bacilli causing neonatal septicaemia. Samples of neonatal blood from 728 suspected cases were obtained in brain heart infusion broth with sodium polyanethol sulfonate. All Gram-negative rods isolated were subsequently subjected to routine antimicrobial susceptibility testing and tests for extended-spectrum P-lactamase (ESBL) production, as per NCCLS recommendations. ESBL was detected in 86.6% of Klebsiella spp., 73.4% of Enterobacter spp. and 63.6% of Escherichia coli strains. It was also observed that 74.4-80.9% of these ESBL producers were resistant to cefotaxime and 47.6-59.5% were resistant to ceftazidime in routine susceptibility testing. Some ESBL producers (36.3-61.5%) were found to be susceptible to either or both cephalosporins used in this study. It is concluded that indiscriminate use of third-generation cephalosporins may be responsible for the selection of ESBL-producing multiresistant strains in the neonatal intensive-care unit (NICU).