To highlight the common presenting symptoms, diagnostic workup and effectiveness of treatments used in various types of autoimmune encephalitis (AE) in children. 

AE is an increasingly recognized cause of encephalitis in which one’s own antibodies target neuronal antigens, leading to an inflammatory CNS disease that presents with a range of neuropsychiatric symptoms, seizures and/or abnormal movements. Despite the limited number of case reports and series of pediatric AE, it is the third most common cause of encephalitis in this population.

Pediatric patients evaluated at UCSF for AE between February 2015-July 2018 were identified from the clinic database. Data were collected from chart review.

Twelve patients were identified with AE [median age at presentation was 10 years (range 2-18), 77% females]. The most common type of encephalitis was steroid-responsive encephalopathy associated with thyroiditis (SREAT) (n=5), followed by anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis (n=3) and glial fibrillary acidic protein (GFAP)-associated encephalitis (n=1). Three of the patients had antibody-negative AE. Only one of the patients with SREAT had a medical and family history of autoimmune disease. The most common presenting symptoms included changes in behavior (58%) and seizures (67%). Brain MRI abnormalities were only seen in 3 patients (NMDAR and GFAP). All patients were surveilled for malignancy, none was identified. Over 90% of patients showed improvement following initial immunotherapy, i.e. IVIG or pulse steroids. 68% of patients also received a 2^nd line immunotherapy treatment (rituximab and/or cyclophosphamide). One patient with NMDAR encephalitis died within 65 days of initial presentation despite treatment with pulse steroids, IVIG, plasmapheresis, cyclophosphamide and rituximab. None of the other patients have shown complete recovery or return to baseline function after a median follow-up of 21 months.

AE has a diverse presentation in children. Although there is generally good response to therapy, significant residual deficits may remain.