Abstract
Progressive multifocal leukoencephalopathy (PML) is a rare but often fatal demyelinating disease of the central nervous system (CNS) caused by reactivation of the John Cunningham (JC) virus in immunocompromised individuals, most commonly those with advanced HIV infection. We report the case of a 56-year-old woman initially investigated for possible ovarian malignancy who presented with progressive left-sided weakness, mimicking ischemic stroke. However, the discordance between the clinical presentation and radiological findings prompted multidisciplinary evaluation, which led to the detection of previously unrecognized HIV infection. Subsequent cerebrospinal fluid (CSF) analysis confirmed the presence of JC virus, establishing the diagnosis of progressive multifocal leukoencephalopathy. Despite prompt initiation of antiretroviral therapy, the patient further deteriorated, culminating in death. This case highlights the diagnostic complexity of PML and the importance of considering HIV-related opportunistic infections in atypical neurological presentations.