Cytomegalovirus meningoencephalitis in an immunocompetent host with evolution of cystic encephalomalacia

A previously healthy 2-month-old male presented with fever and seizures. Cerebrospinal fluid (CSF) studies, head computed tomography (CT), and brain magnetic resonance imaging (MRI) studies were unremarkable on admission. After a clinical decline on the second day admission due to cerebral edema a repeat head CT showed loss of gray-white matter differentiation indicative of global anoxic injury. A repeat brain MRI on day 5 revealed diffuse restricted diffusion globally, acute infarction of the right posterior inferior cerebellar artery territory, and left frontoparietal leptomeningitis versus cortical laminar necrosis. A repeat LP was done on day 5 and showed a total nucleated cell count of 42 cells/mm^3 with 39% lymphocytes and 61% monocytes, glucose 52 mg/dL. He made steady clinical improvement with supportive care. CMV was detected on the repeat CSF sample using PCR on day 11 and he was started on ganciclovir for CMV meningoencephalitis. CMV should be considered as an etiology for viral meningoencephalitis even in immunocompetent patients. Our case also shows the classic imaging evolution of CMV meningoencephalitis.