NEUROPHYSIOLOGIC EVALUATION OF CYCLOSPORINE TOXICITY ASSOCIATED WITH BONE-MARROW TRANSPLANTATION

Introduction - Cortical blindness, a rare form of cyclosporine (CSA) n eurotoxicity, has previously been described in only nine bone marrow t ransplant (BMT) recipients. Methods - Our institution averages 35 allo geneic BMT's per year. In the past year we have seen two women with re versible cortical blindness secondary to CSA toxicity. Results - Age ( years) (Case 1; Case 2): 32; 22. Day post-BMT: 41; 50. Peak CSA level (ng/ml): 1159; 632. Both had a history of renal toxicity requiring adj ustment of CSA dosage. MRI - both with diffuse white matter changes. E EG-both with moderate to severe generalized slowing. Visual evoked pot entials were markedly prolonged in both. Auditory evoked potentials: m inimally abnormal; normal. Somatosensory evoked potentials - both norm al. Prompt improvement occurred with discontinuation of CSA. Followup neurophysiologic evaluations were normal, however structural changes r emained on MRI. Conclusion - As neurophysiologic studies closely follo w the clinical status they should be included in the evaluation and fo llowup of CSA neurotoxicity.