Probable Autoimmune Encephalitis Presenting With Catatonia in a Young Woman: A Case Report and Review of the Literature.

ObjectiveTo describe a case of probable autoimmune encephalitis initially misdiagnosed as a primary psychiatric disorder.MethodReview and description of probable autoimmune encephalitis presenting with catatonia in a young woman 6 months post-partum.ResultsA young woman was initially admitted to an outside hospital and was diagnosed with a primary psychiatric condition. She was referred for psychiatric inpatient care, but was denied admission due to labile hypertension. After admission to the medical service (and ICU), she responded to a lorazepam challenge, and made a complete recovery after several weeks of combined treatment with IV methylprednisolone, IV immunoglobulin (IVIG), and rituximab, and was discharged with a diagnosis of autoimmune encephalitis.ConclusionAutoimmune encephalitis should be suspected in patients presenting with labile vital signs, family history of autoimmunity, and new psychosis without a prior history of psychiatric problems. Other important diagnostic considerations include neuroleptic malignant syndrome, substance-induced psychosis, or catatonia secondary to post-infectious immune-mediated encephalitis. While a first psychotic break should always be considered, the presence of autonomic instability, catatonia, seizures, or dyskinesias in a young woman postpartum should prompt a thorough medical and neurological work-up.