Cerebellar ataxia, vertical supranuclear gaze palsy, sensorineural deafness, epilepsy, dementia, and hallucinations in an adolescent male.

We encountered an adolescent male with cerebellar ataxia since age 11, difficulty in vertical gaze from age 2, leg weakness since age 10, and partial epilepsy since age 8. At age 14, he developed visual and auditory hallucinations, as well as mild sensorineural deafness. He was evaluated as having a mitochondrial disorder. No common mitochondrial DNA mutations were detected in the blood. Muscle biopsy revealed nonspecific changes and normal respiratory chain enzyme complexes. He developed progressive cognitive decline leading to diagnosis of dementia at age 15, and intractablepartial epilepsy persisted despite treatment with multiple anticonvulsants. He also had progressive dysphagia requiring gastrostomy tube for nutrition. He required many other diagnostic investigations for neurodegenerative disorders, but was eventually confirmed as having Niemann-Pick disease type C with excessive free cholesterol using filipin staining and zero activity for cholesterol esterification in fibroblast as well as two pathogenic mutations in the NPC1 gene.