Pontocerebellar hypoplasia caused by the TSEN54 mutation: clinical and electroencephalographic characteristics based on 3 cases

Pontocerebellar hypoplasia caused by the TSEN54 mutation is a severe hereditary disease with an autosomal recessive mode of inheritance, which is characterized by a combination of epileptic encephalopathy, motor disorders in the form of spasticity and hyperknesis, dysphagia and central respiratory failure. At birth there may be multiple joint contractures, muscle hypotonia, and central respiratory failure. Epilepsy occurs in 82 % of cases. Seizures may begin after birth, with an average age of onset of 2.5 years. Various types of seizures are noted (febrile seizures, bilateral tonic-clonic, atypical absence, myoclonic, tonic, focal and atonic seizures), usually resistant to antiepileptic drugs. Magnetic resonance imaging reveals hypoplasia of the pons and cerebellum, which makes it possible to distinguish this disease from cerebral palsy. In the literature there are few descriptions of the clinical picture and electroencephalogram of patients. In this regard, our description of 3 cases of epilepsy and electroencephalographic data in patients with TSEN54 mutation (all female) is of interest to child neurologists and epileptologists.

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