Clinical analysis of 103 children with Angelman syndrome

Objective To investigate the correlation between clinical phenotype, electroencephalogram (EEG) characteristics and genotype in children with Angelman syndrome(AS). Methods A total of 103 children with AS at Department of Neurology, Children′s Hospital of Fudan University from June 2017 to June 2018, were included in this study.The information of clinical characteristics, EEG manifestations, genotypes as well as the epileptic outcome were collected retrospectively.The correlations between clinical phenotype, genotype, and epileptic outcome were evaluated. Results (1) Of the 103 cases, 48 were male (46.6%) and 55 were female (53.4%). (2) Genotypes on AS critical region were maternal chromosome 15q11.2-q13 [86.4%(89/103 cases)], paternal uniparental disomy [3.9%(4/103 cases)], imprinting defects [1.9%(2/103 cases)], and mutations in the maternal copy of UBE3A [7.8%(8/103 cases)]. (3) Apparent happy demeanor or smile and general developmental delay were observed in all AS children.Dyskinesia accounted for 98.1% (101/103 cases), followed by oral movement or suck disorders [97.1%(100/103 cases)] and abnormal posture [67.0%(69/103 cases)]. The proportion of acquired small head circumfe-rence or microcephaly, flat occiput or occipital groove and wide-spaced teeth were 61.2%(63/103 cases), 85.4%(88/103 cases) and 44.7%(46/103 cases), respectively.(4) Behavioral problems like fascination with water, sleep problems and feeding difficulties were found in 86.4%(89/103 cases), 89.3%(92/103 cases) and 85.5%(88/103 cases) of the children, respectively.Sleep disorders [94.4%(84/89 cases) vs.57.1%(8/14 cases)] and feeding difficulties [93.3%(83/89 cases) vs.35.7%(5/14 cases)] were more frequently seen in children with maternal absence group, compared those with no absence, and the differences were statistically significant (all P<0.05). (5) Epilepsy was present in 77.7% (80/103 cases) of children with onset age varying from 8 to 72 months and 80.8% (59/73 cases) were developing seizures prior to 3 years old.Children with maternal absence showed more multiple seizure types than those with no absence[41.7%(32/68 cases) vs.0(0 case)], and the difference was statistically significant(P<0.05). Children with well-controlled epilepsy had more atonic seizure, compared with those with poorly controlled seizure [48.3%(14/29 cases) vs.18.5%(4/27 cases)], and the difference was statistically significant(P<0.05). Conclusions Sleep disorders, feeding difficulties in infancy and multiple seizure types are more commonly seen in AS children with maternal absence.Atonic seizure is easier to be controlled over other types of seizures. Key words: Angelman syndrome; Clinical phenotype; Genotype; Epilepsy