Methotrexate-induced epidermal necrosis in a child with osteosarcoma

Abstract

Methotrexate is a folic acid antagonist used to treat psoria-sis, rheumatoid arthritis and neoplasms. It is renally excreted unchanged, at levels of about 90% within 24 hours. Several risk factors for intoxication have been described, including folate deficiency, liver cirrhosis, renal failure or the use of me-dications such as sulfonamides, salicylate and nonsteroidal anti-inflammatory drugs. Adverse cutaneous reactions such as photosensitivity, alopecia, urticaria, mucositis, erythe-ma, desquamation, Stevens-Johnson syndrome (SJS) or toxic epidermal necrolysis (TEN) are well known. Methotrexate epidermal necrosis (MEN) should also be considered because of its severity, its similarity to TEN and the importance of rapidly administering appropriate treatment. Some cases of MEN have been reported in psoriasis patients, in whom the occurrence with an underlying skin disease has been found to be more common.