Prevalence Of Surgical Site Infections And Their Antibiotic Susceptibility Pattern In A Tertiary Care Hospital

Abstract

BACKGROUND: Surgical site infections are responsible for the increasing cost, morbidity and mortality related to the surgical operations and continues to be a major problem even in the hospitals with the most modern facilities and standard protocols of preoperative and antibiotic prophylaxis. Reduction in the infection rate to a minimal level could have significant benefits in terms of both patient comfort and medical resource used. The common pathogenic bacteria in surgical site infections include Staphylococcus aureus, Pseudomonas, Enterococcus, Escherichia coli, Klebsiella, Citrobacter, Acinetobacter. Staphylococcus aureus form a part of normal flora and can be isolated from the nose of the health care individuals. With increase in Multi Drug Resistant Organisms, there is paucity in data regarding surgical site infections caused by these organisms in our hospital.

 AIMS AND OBJECTIVES: To study the incidence of surgical site infections in a tertiary care hospital in South India taking only clean and clean contaminated wounds.

To identify the pathogens responsible for surgical site infections and to study their antibiotic sensitivity patterns.

 MATERIALS AND METHODS: The study was conducted in the Department of Microbiology at a tertiary care hospital in Mangalore. Total of 50 operated cases done during the study period of 3 months were included, where only clean and clean contaminated cases were taken into consideration. Pus sample was collected from each patient with the help of two sterile swabs under aseptic precautions, one for the staining and other for the culture. A direct Gram stain smear of the specimen was examined. The pus swab was inoculated onto Blood agar and MacConkey agar and incubated at 37^oC for 24-48 hours. The isolates were identified by standard method and antibiotic susceptibility testing was be done by Kirby Bauer disc diffusion method as per CLSI.

 RESULTS: The prevalence of Surgical Site Infections was found to be 18% (n=9). Among 9 cases of SSIs, 7 were culture positive (78%). The maximum number of SSIs were seen in patients in the age group of 21- 40 (33.33%) and in the age group of 41- 60 (33.33%); more cases in males - 5 cases (55.55%) and 4 were females (44.45%) were reported. The most common organism causing SSIs was Escherichia coli - 3 isolates (42.90%), Staphylococcus aureus - 3 isolates (42.90%) and 1 isolate was Pseudomonas aeruginosa (14.20%). 2 among 3 Escherichia coli were Extended Spectrum Beta-Lactamase (ESBL) producers. Antimicrobial sensitivity pattern of Escherichia coli, showed 100% sensitivity towards antibiotics- cefoperazone - sulbactam, piperacillin/tazobactam, imipenem, meropenem and colistin. All 3 Escherichia coli isolates were 100% resistant for ampicillin, amoxyclav, ciprofloxacin and ofloxacin. Among the 3 Staphylococcus aureus isolates 2 were methicillin resistant Staphylococcus aureus (MRSA). All 3 isolates of Staphylococcus aureus showed 100% sensitivity for cotrimoxazole, vancomycin, teicoplanin and linezolid. Pseudomonas aeruginosa showed 100% sensitivity for all the antibiotics.

 CONCLUSION: The consequences of Surgical Site Infections (SSIs) can greatly impact patients and the healthcare system. Prevention of SSIs, requires various infection prevention control approaches targeting pre-operative, intra-operative and post- operative cases. Infection prevention control measures should be strictly adhered to by patients and healthcare workers. Strict Antimicrobial Stewardship protocol needs to be followed to prevent and control SSI.