Vidarabine-associated encephalopathy and myoclonus.

Area of Science:

• Neurology
• Oncology
• Infectious Diseases

Background:

• A 24-year-old male underwent bone marrow transplantation for chronic myeloid leukemia.
• Nine months post-transplant, the patient developed disseminated herpes zoster.

Observation:

• Vidarabine therapy (10 mg/kg/day) was initiated for disseminated herpes zoster.
• After 7 days, the patient developed encephalopathy and immobilizing myoclonus.
• Mild hepatic dysfunction was noted as a potential risk factor for toxicity.

Findings:

• Neurological adverse events, including encephalopathy and myoclonus, occurred during vidarabine treatment.
• Symptoms persisted and worsened after vidarabine cessation.
• Supportive care, including hydration and chlordiazepoxide, provided symptomatic relief.

Implications:

• Vidarabine may pose a risk of severe neurotoxicity in immunocompromised patients, particularly those with a history of bone marrow transplantation.
• Careful patient monitoring for neurological side effects during antiviral therapy is essential.
• Management strategies for vidarabine-induced neurotoxicity involve supportive care and potential medication adjustments.