Progressive Multifocal Leukoencephalopathy in a Patient With Myasthenia Gravis and Thymoma

Progressive multifocal leukoencephalopathy (PML) is a rare and fatal disease caused by JC virus. We report a case of PML which developed in a 61-year-old female patient with myasthenia gravis (MG) and thymoma. After 6 years of immunotherapy and chemotherapy she presented with hand weakness followed by progressive decline of consciousness. Serial brain MRI showed rapidly progressive multifocal white matter changes. The JC virus DNA was detected on cerebrospinal fluid. This is a third report of PML in MG.