Carboxypeptidase G2 rescue in delayed methotrexate elimination in renal failure

We report here the case of a 68-year-old woman who presented severe renal f ailure following the first cycle of high dose methotrexate (HDMTX) for the treatment of a cerebral malignant lymphoma. Before HDMTX administration, se rum creatinine value was normal and three days after HDMTX, it reached 457 mu mol/L. Leucovorin rescue, hemodialysis and cholestyramine did not increa se MTX clearance. Because of the persistence of renal failure, and the high risk of important hematological side-effects associated with high MTX plas ma levels, the patient received carboxypeptidase G2 (CPDG2), This allowed M TX plasma levels to decrease by 80% in 15 minutes. No side effects were obs erved and renal function normalized rapidly. In some patients, when high-do se leucovorin associated with hemodialysis and cholestyramine are unable to restore normal MTX clearance, CPDG2 should be considered because it may re present a safe and efficient alternative for the management of MTX intoxica tion.