Background: CDC defines surgical site infection as ‘Infections related to operative procedure that occurs at or near surgical incision within 30 days of operative procedure or within one year if the implant is left in situ’. Surgical site infection (SSI) is 3 most frequently reported nosocomial infection (12%-16%) as per National Nosocomial Infection Surveillance (NNIS).
The aim of this study was to investigate the antimicrobial susceptibility pattern of organisms causing SSI.
Materials And Methods: During a two year study period in a tertiary care hospital, 19,127 patients underwent surgeries in various surgical departments. Of these 517 (2.7%) developed surgical site infection. The surgical wounds were classified by CDC & NNIS criteria into 4 classes. Two wound swabs were taken and processed by standard microbiological techniques. Antimicrobial susceptibility along with testing of ESBLs, MBLs, AmpCB lactamases was done for all isolates causing SSI.
Results: Among 19,127 patients, 517 (2.7%) developed SSI. It was highest in patients of perforation peritonitis (11.99%).Among 517 specimens, 340 (65.76%) showed growth and 177 (34.23%) were culture negative. E.coli (23.33%) was the commonest organism isolated followed by Acinetobacter spp. (16%), Klebsiella spp. (15.66%), Pseudomonas spp. (15.33%), S. aureus (10.33%), S. epidermidis(7.3%), Proteus spp. (6.00%) and Citrobacter spp. (2.66%).Staphylococcus spp. were 100 % sensitive to Vancomycin & Linezolid. (27.5%) S. aureus were MRSA and (17.5%) were Inducible Clindamycin resistant (ICR). Enterobacteriaceae isolates showed maximum sensitivity towards Imipenem, Piperacillin-Tazobactam and Amikacin. Klebsiella spp. (40.62%), E.coli (35.89%), Citrobacter spp. (33.33%), Proteus spp. (26.08%) were ESBL producers. Klebsiella spp. (17.18%), E.coli (10.25%), Proteus spp. (11.11%) and Citrobacter spp. (8.69%) were AmpC producers. Acinetobacter spp. (28.57%) was commonest MBL producer followed by Klebsiella spp. (20.31%), Pseudomonas spp. (18.84%), E.coli (15.38%), Proteus spp. (4.43%) & Citrobacter spp. (11.11%).
Conclusion: In sight of the high incidence of MRSA, ESBL and MDR reported in this study, there is a need for continuous monitoring to determine the susceptibility pattern of the common isolates causing SSI and to emphasize precise empirical therapy. Policies on prescription patterns should be reviewed, which will ensure reduced patient morbidity & mortality related to SSIs.