Anti-N-methyl-d-aspartate receptor encephalitis in Māori and Pacific Island children in New Zealand.
To investigate the incidence and severity of anti-N-methyl-d-aspartate (anti-NMDA) receptor encephalitis in children from New Zealand.



A retrospective case series was undertaken of all children (≤18y) diagnosed with anti-NMDA receptor encephalitis from January 2008 to October 2015.



Sixteen patients were identified with anti-NMDA receptor antibodies in the cerebrospinal fluid, three of whom had an associated teratoma. Fifteen children had Māori and/or Pacific Island ancestry. The incidence of anti-NMDA receptor encephalitis in Māori children was 3.4 per million children per year (95% confidence interval [CI] 1.4-7.0) and the incidence in Pacific children was 10.0 per million children per year (95% CI 4.3-19.8) compared with 0.2 per million children per year (95% CI 0.0-1.0) in children without Māori or Pacific Island ancestry. Sixty-seven per cent of children had a good outcome (modified Rankin Score ≤2) at 2 years' follow-up. This compares unfavourably with other cohorts despite a shorter median time to first-line immunotherapy (13d; range 4-89) and a higher proportion of children being treated with second-line therapy (50%).



Māori and Pacific Island children have a higher incidence of anti-NMDA receptor encephalitis and possibly a more severe phenotype. These data suggest a genetic predisposition to anti-NMDA receptor encephalitis in these populations.
Starship Children's Hospital, Auckland, New Zealand.
Hannah F
0000-0002-3449-9298
HF
Jones
The Children's Hospital at Westmead, Westmead, NSW, Australia.
Shekeeb S
SS
Mohammad
Starship Children's Hospital, Auckland, New Zealand.
Peter W
PW
Reed
Leicester General Hospital, Leicester, UK.
Paul P J
PPJ
Dunn
Victoria University, Wellington, New Zealand.
Richard H
RH
Steele
The Children's Hospital at Westmead, Westmead, NSW, Australia.
Russell C
RC
Dale
Starship Children's Hospital, Auckland, New Zealand.
Cynthia
C
Sharpe
D000293:Adolescent; D000359:Aftercare; D060426:Anti-N-Methyl-D-Aspartate Receptor Encephalitis / Q000208:ethnology* / Q000628:therapy; D002648:Child; D002675:Child, Preschool; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D015994:Incidence; D007223:Infant; D008297:Male; D009520:New Zealand / Q000453:epidemiology; D012189:Retrospective Studies; D012720:Severity of Illness Index; D016896:Treatment Outcome