Age-dependent characteristics and prognostic factors of pediatric anti-N-methyl-d-aspartate receptor encephalitis in a Chinese single-center study.

Abstract

To describe the clinical features and prognosis of pediatric anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis from a single center in northern China. The clinical and laboratory characteristics of hospitalized patients with anti-NMDAR encephalitis, stratified by age, were retrospectively studied. Risk factors including relapse and long-term (follow-up ≥1 year) outcomes were analyzed. A total of 273 patients were included between November 2011 and December 2019, and the average age of onset was 7.5±4.0 years (0.5-15.8 years). Of them, 159（58.2%） were female, and the proportion of females increased with age. Seizures were the most common initial symptom. Movement disorders（86.1%） and psychiatric（82.4%） symptoms were most frequent in the acute phase. In the acute stage, the incidence of movement disorders decreased with age (χ2=10.676, p=0.011), while the proportion of psychiatric symptoms increased with age (χ2=21.85, p<0.001) The recurrence rate was 9.6% (24/250). Demyelination was an independent risk factor for relapse (p=0.006, OR=5.877, 95% CI: 1.658-20.835). Among the 210 patients who were followed up for more than one year, 28 patients had a poor prognosis (mRS ≥3). Onset age (p=0.038，OR=0.844, 95% CI: 0.720-0.991), precursor of viral encephalitis (p=0.007，OR=9.876, 95% CI: 1.878-51.940), and ICU admission (p=0.023，OR=5.924, 95% CI: 1.280-27.064) significantly affected the prognosis. The mortality rate was 2.9%. The characteristics of anti-NMDAR encephalitis in children are age-dependent. Early-onset, the precursor of viral encephalitis, and ICU admission may indicate poor prognosis. Demyelination may be a risk factor for recurrence.