Autoimmune Encephalitis in Acute Care—Pathology, Diagnosis, and Management

Autoimmune encephalitis (AE) is characterized by immune-mediated inflammation of the brain parenchyma, presenting with various neurological syndromes, including but not limited to seizures, altered consciousness, neuropsychiatric symptoms, and movement disorders. A significant proportion of patients with AE develop life-threatening complications that require hospital and potentially ICU admission. These patients present unique diagnostic and therapeutic challenges, presenting with a range of neurological emergencies such as refractory status epilepticus, severe dysautonomia, coma, and respiratory failure. Diagnosis relies on a combination of clinical criteria, detection of autoantibodies in serum and cerebrospinal fluid, neuroimaging, and electroencephalography, though antibody-negative AE poses considerable diagnostic difficulty. Management is centered on prompt initiation of first-line immunotherapies (corticosteroids, plasma exchange, and intravenous immunoglobulin therapy) and escalation to second-line or emerging targeted therapies (e.g., rituximab, cyclophosphamide, IL-6 inhibitors, proteasome inhibitors) in refractory cases, alongside aggressive supportive care for neurological and systemic complications. The prognosis is variable and influenced by factors such as the specific autoantibody, the timeliness of treatment, and the severity of complications. Long-term sequelae, including cognitive and psychiatric impairments, are common among survivors. This review provides a synthesis of current knowledge on AE in acute and intensive care. Given these diagnostic challenges and the potential for severe symptom presentation, the authors believe that this review is an essential addition to the discourse. This review covers pathophysiology, epidemiology, clinical manifestations, diagnostic approaches, immunotherapeutic strategies, management of critical complications, syndrome-specific considerations, prognostication, intensive care unit-related complications, and future research priorities to support optimal care.