Colchicine in the treatment of cutaneous leukocytoclastic vasculitis. Results of a prospective, randomized controlled trial.

BACKGROUND AND DESIGN: Cutaneous leukocytoclastic vasculitis is an inflammatory vascular disease with a variable course. There is no defined therapy for this entity. Contradictory data on the effect of colchicine have been reported. To determine the efficacy of colchicine in cutaneous leukocytoclastic vasculitis, 41 patients were randomly selected to receive oral colchicine, 0.5 mg twice daily, or topical emollients. Response to treatment was judged according to the reduction in the number of lesions. After 1 month, in those patients in whom a complete or no response was achieved, therapy was withdrawn; in those with a partial response, treatment was maintained for the following 2 months. At the end of 3 months, treatment was continued only in those patients in whom a relapse occurred.

RESULTS: Twenty patients in each group completed 1 month of treatment. One patient taking colchicine dropped out because of diarrhea. At the end of the first month of the study, five patients in the control group and four in the colchicine group achieved a complete response. Nine patients who had a partial response (four in the colchicine group and five in the control group) continued to receive treatment for the following 2 months. Three patients in the colchicine group suffered a relapse after discontinuing therapy but experienced remission with reinstitution of therapy. At the end of the 3 month period, 12 patients in the colchicine group and 10 patients in the control group showed no significant response. Complete response was achieved in five patients in the colchicine group and in seven in the control group. At the 1-year follow-up, 10 patients in each group had no clinical evidence of cutaneous vasculitis.

CONCLUSIONS: Colchicine had no significant therapeutic effect in this controlled study. However, the finding that relapse occurred on cessation of colchicine therapy in three complete responders suggests that colchicine can be effective in some patients, despite our negative results.