Young-onset parkinsonism in a Hong Kong Chinese man with adult-onset Hallervorden-Spatz syndrome.

Neurodegeneration with brain iron accumulation (NBIA) is a heterogeneous group of disorders varied in genetic etiologies, clinical presentations, and radiological features. NBIA is an iron homeostasis disorder with progressive iron accumulation in the central nervous systems and is clinically characterized by extrapyramidal movement abnormalities, retinal pigmentary changes, and cognitive impairment. Panthothenate kinase-associated neurodegeneration (Hallervorden-Spatz disease) is the commonest disorder of NBIA with a prevalence of one-three per million.