[Idiopathic hyperammonemia following allogeneic bone marrow transplantation for refractory lymphoma].

Idiopathic hyperammonemia (IHA) is a rare but serious complication of stem cell transplantation. We report a patient with immunoblastic lymphoadenopathy-like T-cell lymphoma who developed IHA 10 days after allogeneic bone marrow transplantation from an HLA-matched unrelated donor. Despite intensive supportive care, the patient died due to this metabolic disorder two days later. Being mindful of the possibility of IHA in patients who develop confusion and respiratory alkalosis soon after stem cell transplantation would allow earlier treatment and might improve the chance of survival.