Enhancing wound healing in recalcitrant leg ulcers with aminolevulinic acid-mediated antimicrobial photodynamic therapy.

Chronic leg ulcers effect millions of people around the world. It is imperative to search for effective treatments for such challenging ulcers. We report the success of aminolevulinic acid-mediated antimicrobial photodynamic therapy (A-PDT) to enhance wound healing of chronic ulcers for 3 patients who were refractory to conventional treatments. These ulcers healed after one to three sessions of A-PDT and there was no recurrence for more than 29 months. Interestingly, no bacteria were isolated from the ulcers after A-PDT treatment. In vitro, A-PDT also inactivated all bacteria isolated from the patients. A-PDT conditioned medium containing IL-6 enhanced keratinocyte migration. The results suggest in addition to bactericidal effects, A-PDT also alters the wound microenvironment. A-PDT may be an effective treatment for patients with recalcitrant infected ulcers.