Niemann-Pick disease type C (NPC) is a rare, progressive genetic disorder that affects the body’s ability to transport cholesterol and other lipids inside cells, leading to their buildup and damage, especially in the brain, liver, and spleen. NPC is a life-limiting disorder. Prognosis depends on age of onset, with earlier onset forms typically progressing more rapidly.

• Cause: Caused by mutations in the NPC1 (most common) or NPC2 gene. These genes are involved in lipid transport within cells. NPC is inherited in an autosomal recessive pattern.

• Features: Highly variable, but may include:

  • Infant/early childhood onset: developmental delays, liver dysfunction (jaundice, enlarged liver/spleen), difficulty feeding.

  • Later onset (childhood to adulthood): progressive neurological decline, problems with coordination (ataxia), vertical gaze palsy (inability to move eyes up/down), speech and swallowing difficulties, seizures, and cognitive decline.

• Diagnosis: Includes genetic testing, filipin staining (in cultured cells to detect cholesterol buildup), and biomarker tests (e.g., oxysterol levels).

• Treatment: No cure. The drug miglustat can slow neurological progression in some patients. Supportive therapies (e.g., physical, occupational, and speech therapy) are essential.