Late-onset neurodegeneration with brain iron accumulation type 1: expanding the clinical spectrum.

We report on two patients with pathologically proven neurodegeneration with brain iron accumulation type 1 (NBIA-1) with late onset and atypical presentations. One patient experienced gradual onset of shuffling gait, rigidity, bradykinesia, and increasing postural instability at age 85 years. He died a few weeks after developing acute hemiballismus at age 90 years. Histopathology revealed marked neuronal loss in the internal segment of the globus pallidum, astrocytosis, axonal spheroids, and extensive iron deposition consistent with NBIA-1. No additional lesions were found to explain the hemiballismus. The second patient experienced fulminant dementia evolving to total disability and death within 2 months. Autopsy showed typical NBIA-1 pathology. We conclude that NBIA-1 pathology can develop at any age, and that the phenotype should be expanded to include late-onset parkinsonism. The relationship to hemiballismus and adult-onset dementia is less clear.