Journal of Pediatric Neurology 2021; 19(02): 113-115
DOI: 10.1055/s-0040-1714105
Case Report

Rett-like Syndrome in a Pediatric Patient—A Challenging Diagnosis

1   Department of Pediatrics, Centro Hospitalar de Vila Nova de Gaia/Espinho, EPE, Vila Nova de Gaia, Portugal
,
Marta Mesquita
2   Department of Paediatrics, Centro Hospitalar Baixo Vouga, Aveiro, Portugal
,
Joana Nunes
3   Division of Neuroradiology, Department of Imaging, Centro Hospitalar de Vila Nova de Gaia/Espinho, Vila Nova de Gaia, Portugal
,
Isabel Alonso
4   UnIGENe and CGPP, IBMC - Institute for Molecular and Cell Biology, i3S - Instituto de Investigação e Inovação em Saúde, University of Porto, Genetyca-ICM, Porto, Portugal
,
Miguel Leão
5   Pediatric Neurology Unit, Department of Paediatrics, Centro Hospitalar Universitário São João, Porto, Portugal
6   Neurogenetics Unit, Department of Medical Genetics, Centro Hospitalar Universitário São João, Porto, Portugal
,
Fátima Santos
7   Neuroscience Unit for Children and Adolescents, Department of Paediatrics, Centro Hospitalar de Vila Nova de Gaia/Espinho, Vila Nova de Gaia, Portugal
,
Marta Vila Real
7   Neuroscience Unit for Children and Adolescents, Department of Paediatrics, Centro Hospitalar de Vila Nova de Gaia/Espinho, Vila Nova de Gaia, Portugal
› Author Affiliations

Abstract

Neurodevelopmental disorders with features overlapping Rett's syndrome frequently remain unexplained in patients without disease-causing variants in MECP2. Variants in IQSEC2 frequently cause nonsyndromic X-linked intellectual disability (XLID), although de novo variants may cause a severe syndrome that resembles Rett and Angelman's syndrome. We report a 7-year-old girl presenting severe neurodevelopmental delay, stereotypic hand movements, hypotonia, autistic-like features, inappropriate laughing/screaming spells, and symmetrical hypomyelination. A whole exome sequencing detected a novel de novo heterozygous truncating variant within the IQSEC2 gene. Variants of IQSEC2 should be considered in patients with Rett–Angelman phenotype spectrum and autistic features when those causes were excluded.



Publication History

Received: 28 January 2020

Accepted: 03 June 2020

Article published online:
10 August 2020

© 2020. Thieme. All rights reserved.

Georg Thieme Verlag KG
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