Reversible tacrolimus-induced neurotoxicity isolated to the brain stem

Diplopia, nystagmus, visual hallucinations, and internuclear ophthalmoplegi a developed in a 30-year-old woman 84 days after she received a matched, un related bone marrow transplant for chronic myeloid leukemia. A regimen of t acrolimus had been administered since the transplantation was performed. MR imaging revealed bilaterally symmetric regions of signal abnormality with abnormal contrast enhancement in the brain stem. No supratentorial abnormal ity was present. Tacrolimus therapy was discontinued, and the symptoms reso lved. MR imaging that was performed 10 days after tacrolimus was discontinu ed showed resolution of the abnormalities.