Successful treatment of a leg ulcer occurring in a rheumatoid arthritis patient under leflunomide therapy

ABSTRACT Objective  We report the case of a leg ulcer in a rheumatoid arthritis (RA) patient under treatment with leflunomide, discuss the influence of the drug on the aetiopathogenesis of the ulcer and describe its successful treatment. Case summary  A 68‐year‐old woman with a 12‐year history of RA developed a leg ulcer after 4 months of leflunomide treatment. Other ulcerogenic factors were ruled out. There were some clinical hints for rheumatoid vasculitis. The ulcer was resistant to ambulant conservative phase adapted wound bed preparation and a split skin transplantation failed. After omission of leflunomide and washout procedure with cholestyramine a second split skin transplantation resulted in complete healing. Discussion  Leflunomide inhibits the division of activated T cells and thus inhibits among others the production of proinflammatory cytokines and the adhesion of cells to the endothelium. These mechanisms may partly explain the possible influence of leflunomide on the perpetuation of the ulcer. Until now, occurrence of vasculitis and leg ulcers has been described in one case each for the novel immunomodulator leflunomide. No successful treatment of a leg ulcer under leflunomide has been described yet. Omission of leflunomide and a washout treatment in our case led to a complete healing. This may indicate a critical role of leflunomide in the maintenance of this slow healing ulcer. Conclusions  An association between leflunomide intake, occurrence of leg ulcers in RA patients and delayed wound healing should be considered.