TREATMENT OF DERMATOMYOSITIS WITH METHOTREXATE

Background: No published data exist on the incidence of liver fibrosis in patients with dermatomyositis treated with methotrexate. Objective : Our purpose was to examine the efficacy, steroid-sparing potential, and side effects of methotrexate in patients with dermatomyositis and to report liver biopsy results in four patients. Methods: A retrospect ive review of all cases of dermatomyositis treated with methotrexate i n a dermatology and rheumatology referral practice was conducted.Resul ts: Of the 10 cases reviewed, seven were of dermatomyositis whereas th ree were of amyopathic dermatomyositis (ADM). Nine patients received o ral methotrexate. One patient received intravenous methotrexate. Impro vement of cutaneous disease occurred in seven (100%) of the patients w ith dermatomyositis and in two (66%) of those with ADM; myositis impro ved in four (57%) of the patients with dermatomyositis. The initial pr ednisone dose was halved after an average of 18 weeks of methotrexate therapy in the patients with dermatomyositis and 13 weeks in the patie nts with ADM. Methotrexate-related side effects occurred in six (86%) of the patients with dermatomyositis and in one (33%) of the patients with ADM. Of the four patients who had liver biopsies, two (50%) showe d mild hepatic fibrosis, resulting in discontinuation of the drug. Bot h patients in whom fibrosis developed had preexisting steroid-induced diabetes mellitus. Conclusion: Although methotrexate is an effective t reatment for dermatomyositis, side effects are common. Patients with d iabetes mellitus should be closely monitored for toxic effects on the liver.