Rapidly progressive dementia in tacrolimus neurotoxicity: rare but reversible

Tacrolimus is an immunosuppressant agent widely used in organ transplantation. Neurotoxicity due to tacrolimus is frequently reported in the literature with varied presentations from tremors to leukoencephalopathy. Drugs used to prevent graft rejection can cause significant morbidity.

A 65-year-old male developed rapidly progressive dementia shortly after liver transplantation. Imaging revealed abnormal signal intensities, symmetrically involving bilateral caudate head and putamen with diffusion restriction mimicking CJD. Blood levels of tacrolimus were repeatedly normal. He improved completely over 4-6 weeks after stopping tacrolimus.

Tacrolimus is used on a daily basis in most post-transplantation patients. Neurotoxicity related to the medications must be kept in the differential list while investigating rapidly progressing dementia. This case highlights the importance of suspecting tacrolimus toxicity even with therapeutic drug levels.