PRKRA-related Dystonia: A Summary of Previously Reported Cases

Abstract

Abstract DYT-PRKRA is a rare autosomal recessive degenerative movement disorder caused by PRKRA mutations. The classical clinical presentation is childhood-onset generalized dystonia with or without parkinsonism symptoms. Limbs and oromandibular muscles are most frequently involved. A review of literature on reports of PRKRA-related dystonia from 2008 to present was conducted through PubMed to provide a synoptic overview of patients’ characteristics regarding this rare condition. Studies were extracted according to the PRISMA protocol, and a total of 15 articles were included in this review summary. The majority of cases were reported in Brazil and Europe, and 84.8% of patients’ symptoms onset before 20 years old. Among the patients, homozygous c.665C > T mutation was the most common PRKRA mutation. Dystonia was generalized in 81.8% of cases, and parkinsonism presentation was observed in 45.5% of patients. Three patients developed dystonia after fever and showed bilateral structure loss of basal ganglia. Four patients’ dystonia improved significantly with vitamin therapy, and four patients demonstrated remarkable dystonia regression in response to deep brain stimulation of globus pallidus interna. Phenotypic heterogeneity in patients’ characteristics was observed in this review, suggesting the possibility of PRKRA-related dystonia being a spectrum disorder. More research is needed to study the underlying etiology and the actual prevalence of PRKRA-related dystonia.