Clinical Features, Treatment Strategies, and Outcomes in Hospitalized Children With Immune-Mediated Encephalopathies.

Background: Autoimmune encephalitis (AE) and acute disseminated encephalomyelitis (ADEM) are immune-mediated brain conditions that can cause substantial neurological sequalae. Data describing the clinical characteristics, treatments, and neurological outcomes for these conditions are needed.

Methods: This is a single-center retrospective review of children diagnosed with AE or ADEM over a nine-year period with discharge outcomes measured by the Modified Rankin Score.

Results: Seventy-five patients (23 with ADEM and 52 with AE) were identified. Patients with ADEM had a higher percentage of abnormal magnetic resonance imaging findings (100% vs 60.8%; P < 0.001) and a shorter time from symptom onset to diagnosis (6 vs 14 days; P = 0.024). Oligoclonal bands and serum and cerebrospinal fluid inflammatory indices were higher in patients with AE. Nearly all patients received corticosteroids followed by plasmapheresis or intravenous immunoglobulin, and treatment strategies did not differ significantly between groups. Second-line immune therapies were commonly used in patients with AE. Finally, patients with AE had trends toward longer hospital lengths of stay (21 vs 13 days) and a higher percentage of neurological disability at hospital discharge (59.6% vs 34.8%).

Conclusions: Although patients with ADEM and AE may have similar presenting symptoms, we found significant differences in the frequency of imaging findings, symptom duration, and laboratory and cerebrospinal fluid profiles, which can assist in distinguishing between the diagnoses. Patients in both groups were treated with a combination of immunomodulating therapies, and neurological disability was common at hospital discharge.