Antimicrobial Susceptibility Profile and Phenotypic Screening of Carbapenem-Resistant Enterobacteriaceae Isolated from Pus Samples at a Tertiary Care Hospital

Introduction: Carbapenem-resistant Enterobacteriaceae (CRE) are important multidrug-resistant pathogens causing wound infections. This study was conducted to assess the antimicrobial susceptibility profile and phenotypic screening of CRE isolated from pus samples.

Materials and Methods: This prospective cross-sectional study was conducted in the Department of Microbiology, Bidar Institute of Medical Sciences, Bidar. A total of 100 non-duplicate Enterobacteriaceae isolates from pus samples were included. Isolates were identified by standard microbiological methods. Antimicrobial susceptibility testing was done by Kirby–Bauer disc diffusion method as per CLSI guidelines. Carbapenem resistance was screened phenotypically using imipenem and meropenem discs.

Results: Wound infection was the most common diagnosis, accounting for 58.0% of cases. Females constituted 78.0%, and the most common age group was 21–40 years (52.0%). Most samples were received from the Obstetrics and Gynaecology department (47.0%). Klebsiella pneumoniae was the most common isolate (28.0%), followed by Escherichia coli (27.0%). CRE was detected in 41.0% of isolates. Piperacillin–tazobactam showed the highest sensitivity (78.0%), while highest resistance was observed against ceftriaxone (70.0%), cefepime (57.0%), and ciprofloxacin (54.0%).

Conclusion: The study showed a high prevalence of CRE among pus isolates. Routine culture, antimicrobial susceptibility testing, rational antibiotic use, and strict infection control measures are essential to reduce the spread of CRE