Dapsone treatment of folliculitis decalvans

BACKGROUND: Folliculitis decalvans consists of recurrent patchy painful folliculitis of the scalp causing scarring alopecia. The physiopathology of this condition is still unclear, but is likely a manifestation of chronic neutrophilic bacterial folliculitis. Numerous topical and systemic treatments (corticosteroids, antistaphylococcal antibiotics) have been used with variable results. Based on the dapsone antimicrobial activity and its anti-inflammatory action especially directed to the neutrophil metabolism, we treated two patients with severe folliculitis decalvans with this drug. CASE REPORTS: The patients were treated with dapsone at a daily dose of 75 and 100 mg, respectively for 4 to 6 months. After 1 and 2 months, pustular folliculitis progressively cleared, leaving a residual non inflammatory cicatricial alopecia. When maintaining a dapsone dosage at 25 mg/day no relapse occurred during 3 years and 1 year, respectively. No important adverse effect to dapsone was evidenced. After dapsone withdrawal, a moderate relapse of the disease with pruritus and folliculitis occurred after a few weeks in both cases. The disease relapse rapidly cleared after dapsone reintroduction at a daily dose of 25 mg. COMMENTS: Dapsone at moderate dosage was well tolerated and rapidly effective in treating the two cases of folliculitis decalvans. A long term and low dose (25 mg daily) maintenance treatment avoided disease relapses.