Juvenile Parkinsonism and Cognitive Impairment in a Patient with Compound Heterozygous Variants in the BTD Gene‐ an Unusual Presentation of Biotinidase Deficiency.

This article discusses a case study of a 23-year-old male with juvenile parkinsonism and cognitive impairment due to compound heterozygous variants in the BTD gene, leading to biotinidase deficiency. The patient showed symptoms of stiffness, tremors, delayed development milestones, and cognitive impairments. Treatment with biotin supplementation and dopaminergic therapy showed improvement in motor symptoms but not in cognitive functions. The study highlights the importance of considering biotinidase deficiency in cases of juvenile parkinsonism, especially when accompanied by developmental delays, cognitive impairments, and specific MRI findings. [Extracted from the article]