Predominance of multidrug-resistant Gram-negative organisms as cause of surgical site infections at a private tertiary care hospital in Mumbai, India.

ABSTRACT

Background: This study aims to study the incidence, microbial aetiology and antimicrobial susceptibility of surgical site infections (SSIs) at a private tertiary care hospital in Mumbai, India, and compare it with previously published data from the same institute as well as literature. Methods: This is a prospective observational study done over 6 years (January 2013-December 2018) at a 750-bed private multi-specialty hospital in Mumbai, India, among all patients undergoing clean and clean-contaminated surgeries. Standard guidelines for preventing, diagnosing and classifying SSIs were followed. The incidence rates of SSI (overall and specialty specific), microbial aetiology and antibiotic susceptibility of SSI were calculated and expressed as percentages. Results: A total of 55,553 patients underwent clean and clean-contaminated surgeries during the study period. The overall SSI rate was 1.0% (555 cases). The SSI rate in clean surgeries was 0.97% and in clean-contaminated surgeries was 1.03%. Sixty-five per cent of SSIs were due to Gram-negative bacilli, 30% were due to Gram-positive cocci and 4% were due to Candida. Klebsiella pneumoniae (19%), Escherichia coli (17%), Pseudomonas aeruginosa (13%), Staphylococcus aureus(12%) and Enterococcus (10%) were the top five organisms. The overall susceptibility rate of the Gram-negative isolates to beta-lactam-beta-lactamase inhibitor combinations was 60% and carbapenems was 73%. The prevalence of methicillin resistance in S. aureus was 44% and coagulase-negative Staphylococcus was 84%. The crude mortality rate was 1%. Conclusions: Although the SSI rate is comparable to established international benchmarks, the predominance of multidrug-resistant Gram-negative organisms is a matter of serious concern.