ANNA-1/Anti-Hu associated opsoclonus myoclonus and epilepsia partialis continua: Case report and literature review

Abstract Background Opsoclonus-myoclonus syndrome is a rare clinical condition that has been associated with neuroblastoma. There are few reported cases of the presence of ANNA-1/anti-Hu antibodies in children with neuroblastoma and opsoclonus-myoclonus, all in children less than 3 years of age. Methods We report the new onset of focal seizures without alteration of consciousness and opsoclonus-myoclonus in an 11-year-old girl with ANNA-1/anti-Hu positivity and a paraspinal ganglioneuroblastoma. A systematic review of the literature searching for pediatric cases of ANNA-1/anti-Hu positivity and malignancy was also performed. Results There were 14 cases identified, 8 of which had opsoclonus-myoclonus. While epilepsia partialis continua has been reported in association with several neuronal autoantibodies, association with ANNA-1/anti-Hu has not been reported. Conclusions This is the first report of epilepsia partialis continua in a pediatric patient with ANNA-1/anti-Hu antibodies and neuroblastoma. Testing for anti-neuronal antibodies should be considered in children presenting with either opsoclonus-myoclonus or atypical epilepsy suggestive of epilepsia partialis continua.