Methotrexate and liver toxicity: role of surveillance liver biopsy. Conflict between guidelines for rheumatologists and dermatologists.

Methotrexate has been used successfully for the treatment of psoriasis since 1951, and over the past decade its use has increased significantly in the treatment of psoriatic arthritis and rheumatoid arthritis. The potential for hepatic toxicity remains a concern to physicians who are increasingly using this drug. The American Association of Dermatology has specific guidelines for monitoring the hepatic toxicity of methotrexate in patients with psoriasis.' These recommend a baseline liver biopsy at or near the beginning of methotr-vataP tri-atmPfnt anti aft-r pinih cilmrilttiup ineQp of 1 . a