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Reversible bilateral internuclear ophthalmoplegia associated with FK506
M M Lai1, J B Kerrison, N R Miller
1Wilmer Eye Institute, Johns Hopkins Hospital, Baltimore, MD 21287, USA.
Insights
Calcineurin inhibitors like cyclosporin A and FK506 can cause neurological side effects. This patient experienced seizures with cyclosporin A and vision problems with FK506, both resolving after drug withdrawal.
Area of Science:
- Neurology
- Pharmacology
- Transplantation
Background:
- Neurological complications can arise in organ transplant recipients.
- Calcineurin inhibitors are standard immunosuppressants post-transplant.
- Monitoring drug toxicity is crucial in managing transplant patients.
Observation:
- A cardiac transplant patient developed tonic-clonic seizures during cyclosporin A therapy.
- Seizures resolved upon discontinuation of cyclosporin A.
- Later, the same patient experienced diplopia due to bilateral internuclear ophthalmoplegia while on intravenous FK506.
Findings:
- A temporal link was observed between serum FK506 levels and the onset of internuclear ophthalmoplegia.
- Discontinuation of intravenous FK506 resulted in the prompt resolution of neurological symptoms.
Implications:
- This case highlights potential neurotoxicity associated with calcineurin inhibitors.
- Clinicians should consider neurological monitoring in transplant patients receiving these immunosuppressants.
- Understanding drug-specific adverse effects is vital for patient management and safety.
Abstract:
A 50 year old man developed tonic-clonic seizures while receiving cyclosporin A after orthotopic cardiac transplant. The seizures resolved after cessation of cyclosporin A. Thirteen months later, he developed diplopia from bilateral internuclear ophthalmoplegia while receiving intravenous FK506. A temporal association was found between his symptoms and the serum FK506 concentrations. Withdrawal of the intravenous FK506 led to prompt resolution of the bilateral internuclear ophthalmoplegia.
