Bacterial Profile and Antibiogram of Pathogens Causing Surgical Site Infections at Mnazi Mmoja Hospital in Zanzibar, Tanzania

Abstract

A hospital based cross sectional study was done to determine bacterial profile and antibiogram of pathogens causing surgical site infections at Mnazi Mmoja Hospital in Zanzibar, Tanzania. The study was conducted from May to July 2017. We enrolled a total of 121 patients who underwent different surgical procedures and met study inclusion criteria. Pus swabs were collected and cultured as per standard operating procedures. Bacterial identification was then performed using biochemical tests and Analytical Profile Index test for Enterobacteriaceae (API 20E). Antimicrobial drug susceptibility testing was performed using Kirby Bauer disc diffusion technique. Data were analyzed using Statistical Package for Social Sciences (SPSS) version 21.0. Of 121 patients that were enrolled in the study, 75 (62%) developed surgical site infection (SSI). A total of 106 isolates were recovered from patients with positive culture results. The majority of the isolates, 92/106 (87%) were Gram-negative bacteria. The most predominant bacterium was Pseudomonas aeruginosa, 29/106 (27%) in all surgical Departments. Some of the isolated pathogens were multi-drug resistant (29/106; 27%), including Extended Spectrum Beta Lactamase (ESBL) producers (24/92; 26%), Methicillin Resistant Stahylococcus aureus (MRSA) (3/9; 33%) and Induced Clindamycin Resistance (ICR) strains (2/14; 14%). K. pneumoniae isolates showed the highest resistance towards most tested antibiotics (24.1-100%), and 24% of P. aeruginosa isolates were resistant to meropenem. In conclusion, P. aeruginosa was the most common isolated pathogen from patients with SSI in Zanzibar and the majority of the pathogens showed high resistance to commonly prescribed antimicrobial agents used in the hospital settings.