Microbiology and Antimicrobial Resistance Profile in Patients with Diabetic Foot Sepsis at a Central Hospital in Johannesburg, South Africa

Abstract

<b>Background</b>: Diabetic foot sepsis (DFS) is the leading cause of lower extremity amputations and timely initiation of effective antimicrobial therapy is paramount during its management. This study investigated causative microorganisms and their antimicrobial susceptibility profile in patients with DFS. <b>Materials and Methods</b>: A retrospective review was conducted on patients who were 18-years and older admitted with DFS. Data collected included demographic information, comorbidities, clinical findings, types of specimens collected and results of microscopy, culture, and sensitivity (MC&S), treatment, and outcomes. <b>Results</b>: One hundred and sixty-eight records were found, of which 64.3% were of male patients. The median (IQR) age of males was 58 years (IQR 54-65) compared to 61 years (IQR 54-67) for females. Results of MC&S were available in 63.1% of the records, and <i>E. faecalis</i> was cultured in 16%, <i>P. mirabilis</i> in 10%, and <i>S. aureus</i> in 8% of cases. Amoxicillin/Clavulanic acid was prescribed in 69% of the cases. Resistance to at least one antimicrobial was shown in 88% of <i>S. aureus</i> and 80% of <i>P. mirabilis species</i>. <b>Conclusions</b>: The commonly cultured organisms in patients with DFS were <i>E. faecalis</i> 16%, <i>P. mirabilis</i> 10%, and <i>S. aureus</i>. Amoxicillin/Clavulanic was prescribed empirically in 69% of the cases despite high rates of resistance, and in 37% treatment was not preceded by collection of specimens for MC&S. We therefore recommend collection of specimens for MC&S before initiation of antimicrobial therapy in all patients with DFS.