An unusual complication of immunosuppression in myasthenia gravis: progressive multifocal leukoencephalopathy.

We present a 44-year-old female patient with generalised myasthenia gravis who developed progressive multifocal leukoencephalopathy. She was receiving high dose corticosteroids, azathioprine 200mg daily and high dose intravenous immunoglobulin during relapses. Two months after thymectomy she presented with progressive cognitive decline, asymmetric quadriparesis and ataxia. Two months later she was bedridden. Cranial MRI showed large asymmetric T2 and FLAIR hyperintense lesions in cortical and subcortical structures. Positive CSF PCR of JC virus confirmed the diagnosis. The patient survives with severe sequela which confirms slow progression as typical in nonAIDS cases. This is the second case of progressive multifocal leukoencephalopathy in a myasthenic patient.