An Unusual Case of GRIN2A Mutation Presenting as Progressive Limbic Encephalopathy in an Adult

The glutamate ionotropic receptor NMDA (N-methyl-D-aspartate) type subunit 2A gene (GRIN2A) encodes the GluN2A subunit of NMDA receptors, which are essential for synaptic plasticity and memory consolidation. Mutations in GRIN2A can disrupt these processes, often affecting the pediatric population and causing various neurological disorders characterized by epilepsy, intellectual disability, and aphasia, among other neuropsychiatric findings. We report an unusual presentation of adult-onset GRIN2A mutation-associated progressive limbic encephalopathy (LE), characterized by rapidly progressive cortical atrophy, seizures, aphasia, and neuropsychiatric abnormalities, which ultimately led to the patient's sudden demise. Further research into GRIN2A mutations will improve our understanding of such presentations, guiding enhancements in diagnostic methods and therapeutic approaches.