Effects of the Photodynamic Therapy on microbial reduction of diabetic ulcers in humans

摘要

Diabetes Mellitus is a chronic disease that can lead to lower-limb ulceration. The photodynamic therapy (PDT) is based on light interaction with a photosensitizer capable to promote bacterial death and tissue repair acceleration. This study analyzed the effects of PDT in the repair of human diabetic ulcers, by means of microbiological assessment. The clinical study was composed of 12 patients of both sexes with diabetic ulcers in lower limbs that were divided into two groups, control group (n=6) and PDT group (n=6). All patients were treated with collagenase/chloramphenicol during the experimental period, in which 6 of them have received PDT with methylene blue dye (0.01%) associated with laser therapy (660 nm), dose of 6 J/cm~2 and 30 mW laser power. PDT group received ten treatment sessions. Wounds were evaluated for micro-organisms analysis. It was found a reduction in the occurrence of Staphylococcus aureus in both groups, being that reduction more pronounced in the PDT group. Microbial count was performed on PDT group, showing a statistical difference reduction (p<0.05) when compared before and after the treatment. It is concluded that PDT seems to be effective in microbial reduction of human diabetic wounds, promoting acceleration and improvement of tissue repair quality.