The utility of online haemodiafiltration in methotrexate poisoning.

Summary We report a case of a 56-year-old woman with a high-grade diffuse large B-cell lymphoma who unexpectedly developed toxic plasma levels of methotrexate (MTX) following the first cycle of rituximab-cyclophosphamide, hydroxydanorubicin, oncovin, prednisolone (R-CHOP) with a high-dose MTX chemotherapy protocol. She also developed non-oliguric acute kidney injury secondary to MTX nephrotoxicity. We elected to treat her with online-haemodiafiltration (HDF) and this proved to be efficient with a dramatic response. Rapid clearance of MTX to therapeutic levels was possible within three sessions. Prompt therapy with high-volume online-HDF is an effective choice for rapid MTX clearance and swift reversal of MTX nephrotoxicity.