Background: Diabetic foot ulcer (DFU) complications are the most common cause of morbidity in diabetic patients. Bioptron light therapy is a new adjuvant therapy for wound healing. This study aimed to investigate the effect of polarized light therapy on the healing and microbial nature of DFUs. Methods: Forty type 2 diabetic patients with Wagner grade 1 or 2 DFUs were randomly assigned to one of two groups: the light therapy group, which received Bioptron light therapy using the Bioptron lamp for 12 min three times per week, plus standard wound care, or the control group, which received standard wound care only. Both interventions were given over a 2-month period. Wound surface area, volume, and ulcer microbial cultures were all measured before and after the study period. Results: There was a significant reduction in ulcer surface area between groups in favor of the light therapy group, with a relative ulcer size reduction of 51.44% ± 23.76% compared with 24.5% ± 9.6% in the control group (p < 0.001). Besides, a significant difference was observed between groups in the microbial cultures (p = 0.02); by the end of the 8th week, the number of patients with negative ulcer culture was 12 (60%) in the light therapy group compared with 3 (15%) in the control group. Conclusions: Bioptron light therapy seems to be an effective therapeutic intervention combined with standard care in decreasing wound size and reducing ulcer microbiota for DFUs. It reduces ulcer bacterial infection and speeds up ulcer healing. Trial registration: ClinicalTrials.gov: NCT04446767.
Keywords: diabetic; foot ulcer; microbiota; polarized light; wound healing.