Pancytopenia, mucositis, and hepatotoxicity after intralesional methotrexate injection in a patient treated with peritoneal dialysis

A case of methotrexate toxicity from intralesional treatment of squamous cell carcinoma of the hands in a peritoneal dialysis patient is reported. A 68-year-old Caucasian man receiving peritoneal dialysis for end-stage renal disease complained to his primary care physician of shortness of breath, mouth and hand sores, nausea, and general malaise. Four days before his office visit, the patient received 25 mg of methotrexate intralesionally for refractory squamous cell carcinoma of his hands. The patient had several pustular lesions on both hands. On admission, the patient had a normal complete blood cell count and elevated liver enzyme levels. On hospital day 3, the patient's white blood cell count was 1,300 cells/μL, platelet count was 134,000 platelets/μL, hemoglobin value was 12.4 g/dL, and hematocrit was 37%. Folic acid 1 mg i.v. every six hours and leucovorin 10 mg/m(2) (20 mg) i.v. every six hours was initiated. His serum methotrexate concentration was 0.03 μmol/L on hospital day 6. The leucovorin dosage was increased to 200 mg i.v. every six hours. Platelets were administered, and the patient was switched to four-hour treatments of high-flux membrane hemodialysis for two consecutive days. The patient was discharged on hospital day 14. Mild mucositis was still present, but the patient had improved substantially and was discharged to a rehabilitation facility. A 68-year-old peritoneal dialysis patient who was treated with 25 mg of intralesional methotrexate for squamous cell carcinoma of the hands developed pancytopenia, mucositis, and hepatotoxicity as a result of systemic absorption and prolonged elimination.