Tremor-Dominant Pantothenate Kinase-associated Neurodegeneration

Neurodegeneration with brain iron accumulation (NBIA) includes a rare and heterogeneous group of disorders characterized by iron deposition in the basal ganglia. Pantothenate kinase-associated neurodegeneration (PKAN) is the most common NBIA and has 2 main presentations: typical and atypical, the latter rarely presents with tremor. Our reported patients underwent full neurologic examination, standard brain magnetic imaging, and genetic testing for PKAN. Three patients who had "tremor-dominant" PKAN with a relatively benign course were reported, including 1 with dystonic tremor and 2 with parkinsonian tremor. All 3 patients had homozygous mutations in the PANK2 gene and typical eye of the tiger sign on brain imaging. PKAN (and NBIA in general) may be a potential cause of tremor, thus emphasizing the need to consider this diagnosis even in patients with a clinical diagnosis of essential, dystonic, or parkinsonian tremor.