A case of dopa responsive dystonia due to compound heterozygous TH gene mutation in a Turkish Girl.

A case of dopa responsive dystonia due to compound heterozygous TH gene mutation in a Turkish Girl.

Objectives: Dopa responsive dystonia, also known as segawa syndrome, is a rare autosomal inherited genetic disease with a prevalence of approximately 0.5-1 million. Tyrosine hydroxylase deficiency is called autosomal recessive dopa-responsive dystonia. Fewer than 100 cases have been described so far. An 11-year-old girl with compound heterozygous TH gene mutation-associated dopa-responsive dystonia is presented to raise awareness of this very rare and treatable disease.

Methods: An 11-year-old female patient was admitted to our pediatric neurology outpatient clinic with complaints of gait disturbance and tremor in the hands. There were monotonous speech, depressed mood, bradykinesia, distonic contractions in lower extremities while walking and hand tremor in her neurological examination. These complaints were appeared at the age of nine and worsened in time.

Results: We detected two mutation, c.916C>T p.Arg306Cys likely patogenic and c.1318G>Tp.Ala440Ser variant of unknown significance in TH gene. She was treated with levodopa and benserazide at a dose of 90 mg per day and full recovery was observed in a week.

Conclusions: Mild clinical findings in some cases may cause the diagnosis to be overlooked, and in some, severe findings starting in the neonatal period cause patients to be mistakenly diagnosed with cerebral palsy. In such cases, dopa responsive dystonia should be kept in mind and genetic testing should be performed.
Keywords: dopa-responsive dystonia, Tyrosine hydroxylase deficiency, bradykinesia, depressed mood