Cutaneous involvement of dermatomyositis can respond to Dapsone therapy

Background: Dapsone (4,4-diaminodiphenylsulfone) is a sulfone antibiotic used in the treatment of leprosy, but dermatologists more commonly utilize its anti-inflammatory properties particularly directed against leukocytes to treat various bullous disorders, erythema nodosum, pyoderma gangrenosum, Sweet's syndrome, cutaneous vasculitis, and cutaneous forms of lupus erythematosus. The cutaneous manifestations of dermatomyositis are often resistant to antimalarial and immunosuppressive therapies. Methods: Two patients with cutaneous dermatomyositis unresponsive to combination therapy with prednisone, hydroxychloroquine, quinacrine, and immunosuppressive medications had Dapsone added to their therapy. Results: Both patients showed rapid improvement with the addition of Dapsone. Each had an exacerbation of their cutaneous dermatomyositis on Dapsone with withdrawal and subsequent improvement when the Dapsone was reinstituted. Conclusions: Dapsone therapy for cutaneous dermatomyositis may have a wider role inc treatment for these patients refractory to prednisone and antimalarial therapy.