A clinical case of CNOT3 syndrome in a 10-year-old girl

CNOT3 syndrome is a rare genetic disorder with variable clinical manifestations associated with abnormalities in the 19q13.42 region. The CNOT3 gene encodes a protein involved in the regulation of gene expression and maintenance of RNA stability. Mutations in this gene can lead to multiple disorders, including mental retardation, clinical manifestations from the gastrointestinal tract, and characteristic dysmorphic facial features. In clinical practice, an important aspect is early diagnosis and a multidisciplinary approach to treatment, which may include a gastroenterologist, neurologist, and endocrinologist. In the presented clinical case, a 10-year-old girl was hospitalized in the gastroenterology department with complaints of abdominal pain, nausea, and headaches. She was born from her first pregnancy with normal parameters, but from the age of two she began to manifest atopic dermatitis and perianal dermatitis. In 2019, esophagogastroduodenoscopy revealed distal reflux esophagitis and gastritis. Further examination revealed mental retardation, and the girl is under regular medical observation by a neurologist. Physical examination revealed dysmorphic facial features and hirsutism. Laboratory tests revealed latent iron deficiency, and a normal hormonal profile. Due to excessive hair growth and increased appetite, the girl was referred to an endocrinologist to rule out congenital adrenal cortex dysfunction. Genetic testing revealed a microdeletion in the 19q13.42 region, which is associated with CNOT3 syndrome. This case highlights the importance of an integrated approach to diagnosing and treating children with rare genetic syndromes.

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