Modern Pediatrics. Ukraine. (2026).2(154): 111-116. doi: 10.15574/SP.2026.2(154).111116
Fomenko N. М., Synoverska О. B., Berezna Т. G., Vovk Z. V., Lazurkevych K. О.
Ivano-Frankivsk National Medical University, Ukraine

For citation: Fomenko NМ, Synoverska ОB, Berezna ТG, Vovk ZV, Lazurkevych K О. (2026). Clinical and genetic features of Rett syndrome (cases from practice). Modern Pediatrics. Ukraine. 2(154): 111-116. doi: 10.15574/SP.2026.2(154).111116.
Article received: Nov 14, 2025. Accepted for publication: Mar 16, 2026.

Rett syndrome is a genetically determined, progressive disorder of the central nervous system characterized by significant neurodevelopmental impairment and pronounced regression (OMIM: 300005; ICD-10: F84.2). Clinical and genetic features of Rett syndrome are presented based on the analysis of current literature data and the authors’ own observations.
Aim – to acquaint a wide range of physicians with modern approaches to the diagnosis of Rett syndrome through the use of clinical-genealogical analysis, phenotype assessment, advanced molecular genetic testing, and innovative treatment methods for this complex genetic disorder.
Clinical cases. Clinical cases personally diagnosed and observed by the authors in the Precarpathian population are thoroughly described. The main clinical and phenotypic criteria of the disease are highlighted, reflecting the staging of the disease progression and prognosis. Photographs of one patient are presented, illustrating the characteristic phenotype and peculiarities of her neuropsychological development. The genetic aspects of the disorder and modern approaches to molecular genetic testing are clearly outlined, with emphasis on the mode of inheritance and the specifics of genetic counseling for families. The discussion covers issues of differential diagnosis, modern treatment strategies, and innovative therapeutic approaches.
Conclusions. Knowledge of the core symptom complex of Rett syndrome, as well as modern approaches to molecular genetic testing and innovative treatment methods, will promote early diagnosis, more effective treatment, and better rehabilitation outcomes for children with this complex disorder. Primary care physicians should pay special attention to cases of delay and regression of psychoneurological development delay and regression in combination with autism spectrum disorders in children who did not have complications in the perinatal period, and promptly refer them for consultation with a neurologist and a geneticist.
The study was conducted in accordance with the principles of the Declaration of Helsinki. Informed consent was obtained from the patients' parents to participate in the study.
The authors declare no conflict of interest.
Keywords: hereditary disease of the central nervous system, MECP2 gene, neurodevelopment, regression, girls.

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