Extended Spectrum B-Lactamase (ESBL) and Metallo B-Lactamase (MBL) Production in Gram-Negative Bacteria isolated from Urinary Tract Infection Patients.

Abstract

Background: The rate of infections caused by Morganella species is reported to be affected by difficulties in their isolation. Enterobacter, species, Citrobacter freundii, Serratia marcescens, and Morganella morganii are the major pathogens involved in hospital acquired infections. All of them are extensively reported in the infections of urinary tract, respiratory tract, cutaneous disorders, catheter associated infections and infections of the central nervous system.Objective: To investigate the frequency of ESBL producing bacteria in Urinary Tract Infection. Material and Methods: A cross-sectional study of 200 urine samples was collected from the outdoor patient departments of Khyber Teaching Hospital Peshawar through consecutive sampling technique during April, 2019 to June 2019. The urine samples were collected and then cultured on selective media i.e., Cysteine Lactose Electrolyte Deficient Agar (CLED) and on MacConkey agar plates. Isolates were identified by conventional morphological and biochemical tests while antibiotic susceptibility was analyzed by “Agar disc diffusion method” using different antibiotics and their zone of inhibition was measured. Results: Total 200 samples processed, 125 (62.5%) isolates, including 67 (53.6%) females, tested positive for the growth of Gram-negative bacteria. Among the identified species, 76 (60.8%) isolates produced ESBLs, with Escherichia coli accounting for 32.6%, Enterobacter for 23.2%, and Morganella species for 12.0%. Moreover, 77 (61.6%) of the isolates were found to be MBL positive, with 30 (24.0%) of them being E. coli, 28 (22.4%) being Enterobacter, and 19 (15.2%) being Morganella spp. The isolates formed a zone of inhibition like a clover leaf and demonstrated a sensitivity of 85 (68%) to antibiotics in the carbapenem class, such as imipenem and meropenem. Cefoparazone/Sulbactam 80 (64.0%), Ofloxacin 79 (63.2%), and Amikacin 78 (62.4%) were the next three antibiotics with high sensitivity. Ampicillin 106 (84.8%) showed the highest resistance, followed by Nitrofurantoin 84 (67.2%) and Ceftriaxone 79 (63.2%), in that order. Conclusion: The study indicated that ESBL-producing bacteria were present frequently among UTI patients. Most of the isolates exhibited strong carbapenem class antibiotic sensitivity. The findings of this study may contribute to the formulation of tactics to lower the incidence of ESBL-producing UTI.Keywords: Antibiotics resistance, Gram Negative bacteria, Plasmid-mediated enzymes, UTI.