Nationwide survey of childhood Guillain-Barré syndrome, Fisher syndrome, and Bickerstaff brainstem encephalitis in Japan

A systematic review of the epidemiology of pediatric autoimmune encephalitis: disease burden and clinical decision-making

“…The studies from Denmark and Hong Kong had longer data collection periods (2011–2017 and 2009–2015, respectively) and reported higher incidence estimates, at 4.2 and 2.2 cases per million children per year, respectively ( 18 , 31 ). The four studies that did not report incidence estimates out of the pediatric population included two that reported incidence estimates of NMDAR-AIE in specific ancestral or ethnic subpopulations ( 30 , 32 ), and two that reported incidence estimates of other AIE subtypes, including post-infection AIE among children < 3 years with seizures, and Bickerstaff brainstem encephalitis ( 27 , 29 ).…”

“…All except one study ( 32 ) reported the criteria for defining AIE and/or valid methods for detecting antibodies in serum or cerebrospinal fluid (CSF). Three studies had missing data, which included one with only 50% response rate ( 29 ), one with incomplete reporting of incidence estimates by encephalitis cause ( 28 ), and one with unclear reporting of drop-outs ( 27 ). It was also found that all 11 studies reporting proportion data that were used to generate incidence estimates had conducted robust data analyses that included all patients in the sample ( 11 , 19 , 21–24 , 33–36 , 38 ).…”

“…Two studies reporting incidence estimates for NMDAR-AIE reported only on children in specific ancestral or ethnic subpopulations ( 30 , 32 ). Only three studies reported results for specific AIE subtypes, including GAD-65 AIE and antibody-negative AIE ( 18 ); post-herpes simplex virus (HSV) infection AIE in children with seizures under 3 years ( 27 ), and Bickerstaff brainstem encephalitis ( 29 ). Reporting was sparse and disparate across geographies, with no incidence studies from the US, South America, Africa or Central Asia.…”