DETECTION OF CARBAPENEMASE PRODUCING GRAM NEGATIVE BACTERIA IN A TERTIARY CARE HOSPITAL, CHATTOGRAM

Dr. Sharmin Akhtar* and Professor Dr. Md. Ehsanul Hoque

ABSTRACT

Background: The global dissemination of carbapenemase in Gram negative bacteria is a severe public health concern worldwide because of their resistance to most antibiotics. Carbapenemase-producing Gram negative isolates are usually extensively drug resistant, and infections caused by these pathogens with significant morbidity and mortality present a serious clinical challenge. Aim & Objectives: This study was conducted to determine the prevalence of carbapenemase producers in urine and wound-swab along with antimicrobial resistance patterns of these organism. Methodology: Nonduplicate Gram negative bacteria were included in this study from inpatients of Chittagong Medical College Hospital. Antimicrobial susceptibility was done among Gram negative isolates. The modified carbapenem inactivation method was performed to see carbapenemase producers among meropenem resistant isolates. Finally carbapenemase genes were detected by multiplex PCR. Result: Among 300 samples 171 culture positive isolates showed 22.80% Escherichia coli, 26.90% Klebsiella spp., 38.01% Pseudomonas spp., 11.11% Acinetobacter spp. and 1.69% Proteus spp. Antimicrobial susceptibility tests revealed that the ciprofloxacin (78.36%), ampicillin (98.2%), ceftriaxone (71.34%), cefuroxime (77.77%), and ceftazidime (70.76%) were the most resistant, while amikacin (18.71%), pipercillin-tazobactam (25.73%), and meropenem (27.38%) had the lowest resistance. Among Gram negative isolates 21.63% were found to be carbapenemase producers by mCIM and 25% carbapenemase genes were detected by multiplex PCR. Multiplex PCR showed blaNDM gene in 86.04% isolates, bla-VIM in 2.32%, blaKPC+blaNDM+blaOXA-48 in 6.97%, blaKPC+blaOXA-48 in 2.32% and blaNDM+blaOXA-48 in 2.32% isolates. Conclusion: The study shows that rapid dissemination of blaNDM in Bangladesh demands the effective measures along with antibiotics policies in hospital which combact the spread of resistane strains. Moreover accurate detection of the genes related with carbapenemase production by molecular method like multiplex PCR overcome the limitation of phenotypic method.

Keywords: Modified carbapenem inactivation method, New Delhi metallo-beta-lactamase, Oxacillinase, Verona Integron-encoded metallo-beta-lactamase, Multiplex Polymerase Chain reaction.