Infection in diabetic foot

Abstract

Objectives The present study was carried out to determine the prevalence of aerobic and anaerobic pathogens in diabetic foot infections (DFIs), detect their susceptibility to different antimicrobial agents, investigate the microbiological profiles of DFIs in relation to different grades of Wagner classification, and assess the risk factors for DFIs. Background DFI is the most frequent reason for diabetes-related hospitalization. It develops because of several diabetes-related factors including arterial insufficiency, neuropathy, foot deformities, previous ulcers, previous amputation, and local trauma. Materials and methods The study was carried out on clinical specimens taken from 100 diabetic patients (50 patients had type I insulin-dependent diabetes mellitus (IDDM) and 50 patients had type II noninsulin-dependent diabetes mellitus (NIDDM) and 50 nondiabetic patients with foot infection during the period from May 2011 to July 2012. The specimens were cultured using aerobic and anaerobic microbiological techniques, and antibiotic susceptibility testing was performed according to the methods recommended by the Clinical and Laboratory Standards Institute (CLSI). Multidrug-resistant organisms were detected including oxacillin-resistant and vancomycin-resistant staphylococci and gram-negative bacilli extended-spectrum beta-lactamase producers. Results DFIs were polymicrobial in 76% of cases. Staphylococcus aureus was the most common aerobic isolate (17.6%) (including 74.4% methicillin resistant and 23.1% vancomycin resistant). Peptostreptococcus spp. were the most common anaerobic isolate (39.4%). Extended-spectrum β-lactamase production was detected in 53.4% of Gram-negative bacilli. About 62% of diabetic patients were infected with multidrug-resistant organisms. The risk factors for DFIs were duration of diabetes more than 1 year, random blood sugar of at least 200 mg/dl, trauma, previous ulcer and amputation, and comorbidities related to diabetes. Conclusion Imipenem was the most effective drug against all isolates. Effective glycemic control and educating patients on the prophylactic foot care are of key importance for decreasing DFIs.