Epilepsy and cataplexy in Angelman syndrome. Genotype-phenotype correlations. (September 2016)

• Record Type: Journal Article
• Authors: Granild Bie Mertz, Line; Christensen, Rikke; Vogel, Ida; Hertz, Jens Michael; Østergaard, John R.
• Is Part Of: Research in developmental disabilities. Volume 56(2016:Sep.)
• Page Start: 177
• Page End: 182
• Publication Date: 2016-09
• Subjects: Angelman syndrome -- 15q11.2–q13 -- Epilepsy -- Seizures -- Cataplexy; Developmental disabilities -- Periodicals; Developmentally disabled -- Research -- United States -- Periodicals; Developmentally disabled children -- Education -- Research -- United States -- Periodicals; Developmental Disabilities -- Periodicals; Disabled -- Periodicals; Mental Retardation -- rehabilitation -- Periodicals; Personnes atteintes de troubles du développement -- Recherche -- États-Unis -- Périodiques; Enfants atteints de troubles du développement -- Éducation -- Recherche -- États-Unis -- Périodiques; Développement, Troubles du -- Recherche -- États-Unis -- Périodiques; 616.858800
• DOI: 10.1016/j.ridd.2016.06.002
• Languages: English
• ISSNs: 0891-4222

Abstract

Highlights: All children with AS due to a deletion developed epilepsy. Epilepsy onset occurred significantly earlier among children with deletion compared to children with UBE3A mutation or pUPD. Laughter-induced postural muscle tone loss occurred only among deletion cases. We found no differences in severity of epilepsy between children with Class I or Class II deletions. The drugs most frequently prescribed were benzodiazepines in monotherapy, or a combination of benzodiazepines and valproic acid. Abstract: Background: Angelman syndrome (AS) is a neurogenetic disorder characterized by intellectual disability, epilepsy, and low threshold for laughter. Aims: We investigated the occurrence and severity of epilepsy and laughter-induced loss of postural muscle tone determined by the different genetic subtypes. Methods: This study included 39 children with AS. Deletion breakpoints were determined by high resolution CGH microarray (1 × 1 M Agilent). Clinical data were based on a parent interview and medical record review. Results: All patients with AS based on a deletion had epilepsy. Epilepsy was present in 3/4 children with UBE3A mutation, and 4/5 with pUPD. Onset of epilepsy occurred earlier in deletion cases compared to pUPD or UBE3A mutations cases. Laughter-induced postural muscle tone loss occurred only among deletion cases. We found no differences in severity of epilepsy between children with a larger Class I or a smaller Class II deletions, or between the total group with a deletion compared to children with pUPD or a UBE3A mutation. The drugs most frequently prescribed were benzodiazepines in monotherapy, or a combination of benzodiazepines and valproic acid. Conclusion: Epilepsy is very common in patients with AS, especially in patients with a deletion. Postural muscle tone loss and collapsing during outbursts of laughter were seen in patients with a deletion only.