Beyond the Eye of the Tiger: A Case Report of Adult-Onset Pantothenate Kinase-Associated Neurodegeneration Mimicking Progressive Supranuclear Palsy-Parkinsonism.

Pantothenate kinase-associated neurodegeneration (PKAN) is an autosomal recessive neurodegeneration with brain iron accumulation disorder that usually begins in childhood or adolescence; very late adult presentation can resemble more common atypical parkinsonian syndromes. We report a 54-year-old woman whose neurologic symptoms began insidiously at approximately 47 years of age with gait and balance impairment, retropulsive falls, micrographia, and dysarthria. Dysphagia, choking on liquids, urinary incontinence, and loss of independence evolved later. She had been labeled as having progressive supranuclear palsy (PSP)-parkinsonism and had no clear sustained response to escalating dopaminergic therapy. During the month before admission, dysphagia and microaspiration accelerated, culminating in acute hypoxic and hypercarbic respiratory failure requiring intubation. Review of outside records showed bilateral globus pallidus and putaminal hypointensity on brain magnetic resonance imaging (MRI), a distribution compatible with neurodegeneration with brain iron accumulation in the appropriate clinical context, and markedly reduced DaTscan uptake in both putamina with reduced right caudate uptake. The available MRI summary did not preserve the exact sequence used to demonstrate basal-ganglia hypointensity and did not document a definite eye-of-the-tiger sign; therefore, low signal was not treated as specific for iron in isolation. Outside molecular testing was documented as identifying pathogenic PANK2 variants, supporting the treating team's diagnosis of PKAN, although allele-level nomenclature and zygosity were not retained in the available record. Failed extubation led to tracheostomy and percutaneous endoscopic gastrostomy placement. This case illustrates a PSP-like late-adult PKAN phenotype in which chronology, careful interpretation of basal ganglia MRI abnormalities, and molecular testing redirected the diagnosis.