COMPARISON OF TREATMENT OUTCOMES IN DIABETIC FOOT INFECTIONS USING DEEP TISSUE CULTURE AND SURFACE SWAB CULTURE

Abstract

Background: Diabetic foot infections are a major cause of morbidity, prolonged hospitalization, and lower limb amputations among patients with diabetes mellitus. Surface swab cultures may not reliably represent deep tissue pathogens, whereas deep tissue cultures are considered more specific. Comparing treatment outcomes based on these culture techniques may help optimize management strategies and improve healing outcomes in diabetic foot infections. Aim: To compare the outcomes of diabetic foot infections treated based on deep tissue culture versus swab culture. Materials and Methods: This prospective comparative study was conducted in the Department of General Surgery over a duration of 10 months. A total of 56 patients with diabetic foot infections were included in the study and randomly divided into two groups of 28 patients each. Group A patients received treatment guided by deep tissue culture sensitivity, while Group B patients were managed according to swab culture sensitivity reports. Wound assessment included ulcer grade, presence of discharge, necrosis, cellulitis, and signs of systemic infection. Appropriate antibiotics were administered. Outcome measures included wound healing rate, duration of hospital stay, need for surgical intervention, infection resolution, and amputation rate. Statistical analysis was performed using appropriate tests, and p-value less than 0.05 was considered statistically significant. Results: Majority of patients belonged to the age group of 51–70 years, accounting for 35 (62.5%) cases, with male predominance observed in 38 (67.9%) patients. Wagner grade II and III ulcers constituted most diabetic foot lesions. Polymicrobial growth was more commonly identified in deep tissue cultures compared to swab cultures. Concordance between swab and deep tissue culture organisms was observed in only 17 (60.7%) cases. Complete wound healing was achieved in 19 (67.9%) patients in the deep tissue culture group compared to 11 (39.3%) patients in the swab culture group (p = 0.03). Mean duration of hospital stay was significantly lower in Group A (11.2 ± 3.4 days). Major amputation was required in 2 (7.1%) patients in the deep tissue culture group and 6 (21.4%) patients in the swab culture group. Conclusion: Deep tissue culture-guided management was associated with superior clinical outcomes compared to swab culture-guided therapy in diabetic foot infections. Deep tissue culture should be considered the preferred microbiological method in the management of diabetic foot infections.