Hallmarks for early recognition of anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis: A case report and review of literature

Abstract

Anti-N-methyl-D-aspartate receptor (Anti-NMDAR) encephalitis is an under-recognized progressive neurological disorder caused by antibodies against the GluN1 (NR1) subunit of NMDA receptors in the brain. It is characterized by the subacute development of neuropsychiatric symptoms, movement disorders and seizures, often evolving into a severe and disabling encephalopathy with detrimental consequences over the functionality of affected individuals. The variable clinical presentation and infrequency with which it is clinically encountered presents a formidable diagnostic challenge in primary care. Initial misdiagnosis as psychiatric disease or infectious encephalitis significantly delays diagnosis and treatment of this medical condition. We present the case of a 34-year-old male who was evaluated after being transferred from a psychiatric institution due to worsening neuropsychiatric symptoms and seizures. Symptoms were preceded by new onset headaches, followed by behavioral changes, movement disorders, and a myriad of symptoms that pointed towards a psychiatric disorder. The non-specific nature of the presenting signs and symptoms of this patient led to initial misdiagnosis and delay of treatment. Thus, recognizing key elements of the patient’s clinical presentation and progression are of paramount importance. Our aim is to highlight key clinical and diagnostic findings that could help clinicians consider anti-NMDAR encephalitis in the differential diagnosis of patients presenting similarly as our patient did, as well as to present a review of literature of this unique neurological condition.