Low prevalence of high-dose methotrexate nephropathy in patients with malignancy.

Introduction: Methotrexate is an antifolate medication frequently used in the treatment of malignant and nonmalignant diseases. The usage of high-dose methotrexate was limited to patients with osteosarcoma, Ewing sarcoma, lymphoma, and acute lymphoblastic leukemia. One of the major side effects of high-dose methotrexate is nephropathy. The aim of present study was to determine the renal side effects of high-dose methotrexate in patients with malignancies.

Materials And Methods: In a study of 102 patients with osteosarcoma (n = 72), Ewing sarcoma (n = 15), and lymphoma (n = 15), treated with high-dose methotrexate, clinical and laboratory data including kidney function tests were recorded at baseline and during follow-up visits. The mean duration of follow-up was 6 months.

Results: The mean age of the patients was 19.5 years (range, 5 to 80 years). The total courses of methotrexate therapy were 273 (median, 2.67 per patient). The mean creatinine level was 0.82 mg/dL. Of the 102 patients, 3 (2.9%) developed acute kidney injury with an at risk phase. Another patient (1.0%) developed acute kidney injury and its phase was injury according to the RIFLE criteria. None of the cases were failed and acute kidney injury was alleviated in all of the affected patients.

Conclusions: Our data revealed a low prevalence of acute kidney injury with high-dose methotrexate therapy. In addition, these toxicities were limited to the first and second phases of the RIFLE classification, all of which resolved spontaneously.