Longitudinal Study of Cognition With Niemann-Pick Disease, Type C

Niemann-Pick Disease, Type C (NPC) is a rare neurodegenerative disorder with a wide clinical spectrum and variable age of onset. Classically, children with NPC demonstrate neurological dysfunction with cerebellar ataxia (an inability to coordinate balance, gait, extremity and eye movements), dysarthria (difficulty speaking), seizures, vertical gaze palsy (ability to move eyes in the same direction) motor impairment, dysphagia (trouble swallowing), psychotic episodes, and progressive dementia. There is no curative treatment for NPC and it is a lethal disorder. The purpose of this protocol is to obtain both baseline and rate of progression data on a clinical and biochemical markers that may later be used as outcome measures in a clinical trial. Specifically, this study will examine and characterize the longitudinal progression of neurocognitive symptoms of NPC with the goal of identifying early markers of disease progression that may be utilized in later trials to evaluate treatment efficacy.