Idiopathic Basal Ganglia Calcifications: An Atypical Presentation of PKAN

BackgroundWe report a patient with pantothenate kinase–associated neurodegeneration presenting as idiopathic basal ganglia calcifications, previously known as Fahr's disease.MethodsA teenage girl presented with slowly progressive dystonia. Her brain magnetic resonance imaging scan revealed T1 and T2 hypointensities in both globus pallidi, and no eye-of-the-tiger sign. Computed tomography showed dense globus pallidi calcifications. Metabolic evaluation was negative. The patient was diagnosed with idiopathic basal ganglia calcifications, a poorly understood syndrome of unknown cause. Whole exome sequencing was performed.ResultsThe patient was found to have two mutations in the pantothenate kinase 2 (PANK2) gene that have been previously associated with pantothenate kinase–associated neurodegeneration: a paternally inherited p.G521R and maternally inherited p.T528M. No deleterious changes were identified in genes associated with idiopathic basal ganglia calcifications or dystonia.ConclusionsPantothenate kinase–associated neurodegeneration should be considered in patients with idiopathic basal ganglia calcifications, especially when findings are confined to the globus pallidus.