Anti-N-methyl, D-aspartate receptor (Anti-NMDAR) encephalitis is increasingly being reported among children. It is diagnosed by the presence of antibodies in cerebrospinal fluid (CSF) [1]. Clinical criteria for early recognition include subacute onset of memory deficits, altered mental status and psychiatric symptoms, besides seizures and focal neurological deficits [2]. Appropriate treatment results in a favourable long-term outcome. We describe the presentation, response to treatment and outcome of six children with anti-NMDAR encephalitis.

The age of patients ranged from 2- to 11-years; five out of six patients were girls. Three children had prodromal symptoms (fever, headache and vomiting). All patients presented with seizures and abnormal behaviour. CSF had lymphocytic pleocytosis with normal protein and sugar, and was positive for anti-NMDAR antibody in all patients. EEG and MRI brain did not reveal any specific diagnostic changes. No patient required mechanical ventilation or inotropes. The mean time to improvement was 5 weeks. No patient relapsed during the follow-up period. Expressive aphasia was the last symptom to regress. Two children managed to return to school. There was no mortality. Clinical features and outcome are detailed in the Table I.

TABLE I Clinical Features, Treatment and Outcome of Six Children with Anti-NMDAR Encephalitis

Anti-NMDAR encephalitis was first described in 2007 [1]. A position paper on Autoimmune encephalitis outlines criteria that permit early diagnosis on clinical grounds, given that accurate pathological diagnosis may not be possible in resource-constrained settings [2]. Behavioral abnormality, movement disorders, focal neurological deficits and autonomic disturbances have been described [1,4-8]. In this case series, orofacial dyskinesia and choreoathetosis were diagnostic pointers; life-threatening autonomic disturbances, commonly seen in adults, did not occur. Several options of immunotherapy for this condition have been recommended with varying results [4,5]. This case series is too small to provide a recommendation for optimum treatment.

Armangue, et al. [8], in a series of 20 children, reported a long-term outcome of substantial recovery in 17%, moderate to severe disability in two children, and one death. The median time to improvement was 11.5 days. The last symptoms to improve were related to executive functions. A recent study of Indian children suggests that prepubertal disease is more severe with poor cognitive outcome and persistent psychiatric symptoms [9]. We observed residual behavioral abnormalities, including temper tantrums, emotional lability and insomnia. Reading, writing, memory and speech were affected, which improved over time.

Improved awareness among pediatricians will prompt early recognition and treatment of this devastating disease. Prolonged follow-up for cognitive and psychiatric sequelae is warranted.

Contributors: VMA: clinical management and data collection, study concept and design, and drafted the manuscript; JM: clinical management and follow-up, data collection, concept and design of the study, and drafting and revising the manuscript; PK: clinical management of the cases, concept and design of the study, and critical revision of the manuscript. All authors approved the final version.

Funding: None; Competing interest: None stated.

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8. Armangue T, Titulaer MJ, Málaga I, Bataller L, Gabilondo I, Graus F, et al. Anti-NMDAR encephalitis–clinical analysis and novel findings in a series of 20 patients.　J Pediatr. 2013;162:850-6.