Adverse Reaction to Methotrexate and Etretinate in a Patient with Psoriasis

ABSTRACT

A 49-year-old Caucasian male patient suffered from fever general weakness and diffuse hair loss on the scalp for 3 days. Skin lesions showed erythematous scaly patches with pustules and erosions on the lower extremities and perianal region, and multiple ulcerations on the labial mucoas. A complete blood cell count revealed thrombocytopenia and leukopenia, which gradually worsened day after day (platelet 29, 000/mm², WBC 1,000/mm³). Candida albicans was isolated from the lesions of the oral cavity and lower extremities. Twelve days prior to the visit, he had taken etretinate Tegison®) P.O.25mg/day, prednisolone P.O. 50mg1dy and methotrexate P.O. 15mg/day for 5 days for the treatment of psoriasis. We presume that these adverse reactions may be synergistic adverse reactions, probably due to methotrexate and etretinate in consideration of the patient's history.