Dermatomyositis induced by drug therapy: a review of case reports.

Abstract

Drugs have occasionally been implicated in dermatomyositis (DM) onset. We sought to review case reports of drug-induced DM. Articles were gathered from MEDLINE and bibliographies of acquired reports. Causality was assessed using World Health Organization criteria. Clinical characteristics, management, and resolution were examined. In 70 reported cases, 50% of patients were female and the median age was 57 years. Hydroxyurea was implicated in 51% of cases. All cases had pathognomonic (76%) or compatible (24%) cutaneous findings. Hydroxyurea cases lacked myositis, but myositis was described in 79.4% of nonhydroxyurea cases. Drug causality was probable (25.7%) or possible (74.3%), but not certain in any case. Most patients had underlying pathology associated with DM (44% had malignancy; 16% had rheumatoid arthritis). Of the sample, 84.3% had improvement of DM after discontinuation of the drug. Case reports may emphasize unusual findings. Further work is needed to differentiate drug effects from underlying, predisposing factors.