Short-term clinical effects of photodynamic therapy with topical 5-aminolevulinic acid for facial acne conglobata: an open, prospective, parallel-arm trial.

Background: Acne conglobata is hardly curable and easily leads to scar formation after treatment using traditional methods.

Aim: To develop a novel way to treat acne conglobata.

Methods: Seventy-five patients with facial acne conglobata were included in this clinical study and divided into either a treatment group (n = 35) to receive photodynamic therapy (PDT) with topical 5% 5-aminolevulinic acid and red light once every 10 days for a month or a control group (n = 40) to receive a Chinese herbal medicine mask plus red light once per week for the same duration. Patients in both groups were given oral viaminate capsules, doxycycline, zinc gluconate, and topical metronidazole. Efficacy was evaluated with respect to symptom score, cure rate, and response rate up to 2 weeks following the final treatment, and time points for assessment included baseline (D0 ), the visit before each treatment (D10 and D20 for the treatment group, and D7 , D14 , and D21 for the control group), and 2 weeks after treatment (D34 for the treatment group and D35 for the control group). Safety was assessed by recording adverse effects.

Results: Treatment with PDT significantly improved acne lesions and reduced scar formation. The treatment group had a significantly lower symptom score, a higher cure rate, and response rate than the control group. No systemic side effects occurred.

Conclusion: The treatment of acne conglobata with PDT is associated with a high cure rate, short treatment period, few side effects, and reduced scar formation. To the best of our knowledge, this is the first report on the treatment of acne conglobata with PDT.