Abstract
Pediatric autoimmune encephalitis (AE) remains a diagnostic and therapeutic challenge
in resource-poor settings. Minimizing delay in diagnosis and appropriate escalation
of treatment will help reduce both the short- and long-term neurodisabilities. A retrospective
observational study was performed on children consecutively diagnosed with possible
AE and then prospectively followed up in a single tertiary care children's hospital
in Sri Lanka. Serum and cerebrospinal fluid were tested for neuroglial surface-binding
autoantibodies using cell-based assays in majority of these children. Twenty-five
children (mean age 7.6 years, standard deviation = 4) were recruited. In these children,
presenting symptom was psychiatric in 11 children (44%), seizures in 10 (40%), language
regression in 2 (8%), and combination of psychosis and convulsions in 2 (8%). Psychiatric
presentations were more common in older (>6 years) compared with young children (p = 0.001), while neurological presentations were more common in children aged ≤6 years
(p = 0.001). N-methyl-D-aspartate receptor (NMDAR) antibodies were detected in 9 (45%)
and unspecified voltage-gated potassium channel antibodies in 1 (5%) of the 20 tested.
All received intravenous steroids and immunoglobulins; 19 (76%) plasma exchange; 7
(29%) rituximab. Complete/substantial improvement at 3 months occurred in 64%. Pediatric
Cerebral Performance Category score at last review was 1 (normal function for age)
in 43%. Higher proportion of younger children required less intense therapy and had
better recovery (56%). Death (8%), incomplete recovery (71%), and relapses (8%) were
more in older children. Clinical presentation and disease outcomes were different
in children aged <6 years compared with older age group. NMDAR antibody encephalitis
was the commonest AE syndrome identified in this cohort.
Keywords
children - autoimmune encephalitis - NMDAR - antibody - Sri Lanka
