Features of premorbid status in patients with Rett syndrome

Fedoseeva I.F.; Goncharenko V.A.; Goncharenko A.V.; Poponnikova T.V.; Pinevich O.S.

doi:https://doi.org/10.17116/jnevro2026126021136

Abstract:

Rett syndrome is a severe, progressive developmental condition of the nervous system. It is linked to the X chromosome and affects mainly girls aged 6 to 18 months. The syndrome is usually caused by pathogenic mutations in the MECP2 gene, which encodes a methyl-CpG-binding protein. The prevalence of the disease is 1:10.000 in the female population. This syndrome is characterized by a progressive course, loss of acquired motor, mental, and speech functions, and multisystem comorbidities. A case of Rett syndrome in a 3-year-old child, confirmed by molecular genetic analysis, is presented. The features of premorbid neurological status are described, including delayed speech development and muscle hypotonia, which require increased attention and additional molecular genetic testing for differential diagnosis, given the phenotypic heterogeneity of Rett syndrome.

Keywords:

Rett syndrome

muscle hypotonia

developmental regression

children

MECP2 gene

Authors:

Fedoseeva I.F.

Kemerovo State Medical University

ORCID: 0000-0003-3692-5673

Goncharenko V.A.

Kemerovo State Medical University

ORCID: 0000-0003-0641-0468

Goncharenko A.V.

Kemerovo State Medical University

ORCID: 0009-0008-8805-6784

Poponnikova T.V.

Kemerovo State Medical University

ORCID: 0000-0003-2894-3062

Pinevich O.S.

Kuzbass Regional Clinical Hospital named after S.V. Belyaev

ORCID: 0009-0006-7778-2540

Received:

05.08.2025

Accepted:

31.08.2025

Close metadata

References:

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