Phenotypic Isolation and Characterization of Bacterial Isolates and Incidence of Multi-Drug-ResistantStrains from Surgical Site Infected Patients of Tertiary Care Hospital, Tamil Nadu

Background: Most of the clean and contaminated post-operative surgeries have seen in surgeries of orthopaedics, obstetrics and gynaecology etc. Surgical Site Infection (SSI) had third most priority among nosocomial infections.The main aim of the study is to identify the risk factors and the antibiotic susceptibility testing of bacterial pathogens isolated from post-surgical site infection.Materials & Methods: This prospective laboratory-based study was conducted during the period of six months from February to June 2020.In this study, 37 specimens were selected from different clinical department to the bacteriology laboratory for routine analyses and they were immediately inoculated into the basic culture media and the plates were incubated at 37C for 24 hours overnight incubation to observe the growth.According to CLSI guidelines, Kirby Bauer Disc Diffusion method is used for antibiotic susceptibility testing for the bacterial isolates.Results: Out of 37 samples, 30 had bacterial growth (81.0%) which comprises of Gram positive isolates were CONS 7 (23%) S. aureus 4 (14%), and Klebsiella pneumoniae 6 (20%), Pseudomonas aeruginosa 7(23%), E. coli 6 (20%) were gram negative isolates and the remaining seven (19.0%) were no growth.Clindamycin and Penicillin shows 100% resistant to gram positive cocci.Cefepime, Co-trimaxazole and Ciprofloxacin are predominant resistant to gram negative bacilli. Conclusion:This study concludes that post-operative wound infection is one of the frequent nosocomial infections among surgical patients.Most of the patients were affected in the age group 40 -60 years.Continuous monitoring and surveillance of SSI infection is highly recommended.