Surgical Site Infection at a Central Academic Hospital in Johannesburg: A One-year Audit

Introduction: Surgical site infection accounts for approximately 38% of hospital-acquired infections globally and is associated with increased length of hospitalization and mortality. The aim of the study was to determine the incidence of surgical site infection, causative organisms and factors which were associated with its occurrence at a central hospital in South Africa. Methods: A retrospective review of records of patients who developed surgical site infection over a 12-months period was conducted. Data were extracted from records of weekly morbidity and mortality meetings of the Department of Surgery. Data retrieved included demographic information, co-morbidities, nature of surgery, class of surgical site infection and microscopy, culture and sensitivity results and overall outcome including the length of hospital stay. Results: During the study period 3 005 surgical procedures were performed of which 46.8% were elective operations. A total of 147 records of patients who developed surgical site infection were found. The mean age of these 147 patients who developed surgical site infection was 47.3±17.21 years. The incidence of reported surgical site infection was 4.8% (147/3 005) with 72.6% (93/147) occurring in males. Nineteen of the 147 cases had to be excluded and thus only 128 patient files were suitable for the study. Of patients who developed surgical site infection, 30.5% (39/128) had diabetes mellitus, 21.9% (28/128) had hypertension and 18.8% (24/128) had both diabetes and hypertension, while 15.6% (20/128) of patients were known to be HIV positive. Sixty-four percent (64.1%: 82/128) of the patients who developed SSI had positive culture results and the two most commonly cultured organisms were E. coli (44%, 36/82) and P. aeruginosa (29.3%, 24/82). Conclusion: The overall rate of occurrence of surgical site infection was 4.8% and most of the infections were diagnosed in male patients. The two most commonly cultured organisms were E. coli and P. aeruginosa. Thirty-one percent who had surgical site infection had diabetes mellitus.