Cyclosporin-associated central nervous system toxicity after allogeneic bone marrow transplantation.

Five of 64 recipients of HLA-identical sibling marrow allografts who were given cyclosporin (CSP) to minimize graft-versus-host disease posttransplant had a serious neurological illness thought to be due to CSP. Characteristic clinical features included a motor spinal cord syndrome, a cerebellar-like syndrome, and mental confusion. All five recovered when the CSP dose was reduced or the drug was stopped.