Immunosuppression‐induced leukoencephalopathy from tacrolimus (FK506)

Abstract
Tacrolimus (FK506) has recently been approved for immunosuppressionin organ transplantation, although its use is accompanied by a wide spectrum ofneurotoxic side effects. We describe the clinical, radiological, and pathological features of 3 cases of tacrolimus‐related leukoencephalopathy. The syndrome of immunosuppression‐related leukoencephalopathy is proposed as an uncommon neurological syndrome occurring in patintw with organ transplants involving demyelination, in particular in the parieto‐occipital region and centrum semiovale. Although the syndrome is not associated with a particular (absolute) serum level of tacrolimus, it resolves spontaneously upon decreasing the dose. The tacrolimus‐related syndrome has a similar radiographic and pathologic appearance as the analogous syndrome that occurs in patients taking cyclosporine.