UC Irvine

The principal toxicities of methotrexate sodium are myelosuppression, oral and gastrointestinal tract mucositis, and hepatitis. Other uncommon toxicities also include liver cirrhosis, interstitial pneumonitis, osteoporosis, alopecia, and immune dysfunction.^1,2 Over the past several years, high-dose methotrexate and leucovorin calcium-containing regimens have been introduced in the treatment of histiocytic lymphoma with an eye toward its cure, and their superior value to conventional regimens has been well demonstrated.^3-5 With high-dose methotrexate therapy, the toxicities have been more frequent and severe, and other side effects such as renal dysfunction, vasculitis, conjunctivitis, rhinorrhea, headache, hypertension, and seizure also have been observed.^2,6,7In this communication, three patients are described in whom the previously unreported side effects of severe multiple bullous dermatosis and onycholysis developed due to high-dose methotrexate and leucovorin calcium administration, which were serious enough to disrupt their chemotherapy schedules.