A cross-sectional study to estimate the prevalence of bacterial pathogens causing surgical site infection in a tertiary care setup

Background: As per CDC updates 2007, post-operative wound infections are very common Health Care-Associated Infection. Aim and Objective: The present was done to surgical site infection in a tertiary care set up in Eastern India. Materials and Methods: The study was conducted in the Department of Microbiology of a tertiary care set up from January to December 2017. The total number of elective and emergency surgeries done during the study period was 298 which included 79 elective (major) and rest, emergency cases. Forty-nine cases were clinically suspected to be postoperative wound infection, studied as per standard microbiology guidelines. Results: Median age was 45 years (Female: 26, Male: 23). From twenty-seven samples, bacterial pathogens were isolated. The most common microorganism was found to be Staphylococcus aureus (13 out of 27, i.e. 48.14%). No polymicrobial involvement was found. Regarding antimicrobial susceptibility pattern, amongst 13 isolated S. aureus, 5 i.e., 45.45% were Methicillin-Resistant S. aureus and all the Staphylococcus isolates were sensitive to Vancomycin and Linezolid. All the Gram-negative isolates were sensitive to colistin. All the isolated Pseudomonas spp., one Klebsiella spp. isolate and one Acinetobacter spp. isolate were carbapenemase producers. Five out of 14 Gram-negative isolates were Extended spectrum beta lactamase (ESBL) (35.71%) whereas three isolates seem to be Amp C beta-lactamase producer(21.42%). 7 of 13 Staphylococcus isolates (53.84%), 4 out of 7 Escherichia coli isolates (57.14%), one Klebsiella spp. And all Pseudomonas as well as Acinetobacter isolates were resistant to fluoroquinolones. Out of the 14 Gram-negative isolates, in more than half of the occasions (8/14, i.e, 57.14%), were either ESBL or Amp C beta-lactamase producer or sensitive to carbapenems. Conclusion: Increased resistance of Gram-negative isolates against beta lactam antimicrobials alarms to select empirical antimicrobials judiciously.