Abstract: We reported 3 cases of disseminated flat warts treated with photodynamic therapy combined with CO₂ fractional laser and reviewed related literature. Case 1 had generalized rash on the head, face, trunk, and limbs lasting for 5 years. Case 2 and 3 had multiple papules on the head and face for more than 2 years. The diagnosis of disseminated flat warts was made according clinical manifestations and dermoscopy. After 2-3 treatments of photodynamic combined with CO₂ fractional laser, the skin lesions of 3 patients were completely cleared, without serious adverse reactions and recurrence after follow-up. It showed that the treatment efficiency of fractional laser pretreatment before photodynamic therapy for flat wart was 96.4% by reviewing the literature. This combination therapy with exact effect and mild adverse reactions provided a reference for the treatment of disseminated flat warts.

Key words: disseminated flat wart, photodynamic therapy, CO₂ fractional laser