Ulcerations in chronic plaque psoriasis: A diagnostic clue for acute methotrexate toxicity

An elderly male patient, a known case of psoriasis vulgaris, presented with ulcerations in preexisting psoriatic lesions. The patient had fever with chills and severe pain and burning sensations in the lesions. There was a history of intramuscular methotrexate (Mtx) injection 15 mg followed by oral Mtx 7.5 mg once daily from next day for 5 days. Laboratory investigations revealed severe pancytopenia and abnormal renal and liver function tests. A diagnosis of acute Mtx toxicity was made and started treatment with intravenous leucovorin and subcutaneous granulocyte colony-stimulating factor (filgrastim) for 4 days. The patient responded to the treatment with improvement in skin lesions and laboratory parameters. The present case underlines the importance of patient counseling regarding the dosage schedule of the drugs and their adverse effects. The ulceration of preexisting lesions helps in early diagnosis, evaluation, and initiation of specific therapy.