Dopa-responsive dystonia induced by GCH1 gene mutation: a case report

Abstract

Dopa-responsive dystonia（DRD） is an autosomal dominant or recessive dyskinesia, which is pathologically characterized with reduced amount of dopamine in the substantia nigra and striatum. DRD is mainly manifested with dystonian in early childhood. Low-dose levodopa can mitigate relevant symptoms. Guanosine triphosphate cyclohydrolase I （GCH1） gene is the pathogenic gene of DRD. In this article, 1 child diagnosed with DRD induced by GCH1 gene mutation was reported. Gait abnormality was the chief complaint. The child showed dystonic posture when walking. These symptoms were mitigated in the morning and aggravated during night. Gene detection confirmed the incidence of heterozygous mutation of GCH1 gene. The neurological symptoms of this child were basically cured after low-dose levodopa therapy. During 2-year follow-up at Department of Pediatric Neurology, motor function was restored to normal. In clinical practice, the possibility of DRD should be considered for pediatric dystonia with unknown causes. Prompt diagnosis and treatment can significantly improve clinical prognosis and prevent the incidence of disability.

Keywords

• |dopa-responsive dystonia|gch1 gene|levodopa