Niemann-Pick disease type C

This code identifies Niemann-Pick disease type C (NPC), a rare, inherited lysosomal storage disorder characterized by the inability to properly transport and metabolize lipids within cells. This leads to the accumulation of cholesterol and other fatty substances in the brain, liver, spleen, and other organs, causing progressive neurological deterioration and visceral organ involvement.

Assign this code for patients diagnosed with Niemann-Pick disease type C, based on genetic testing, biochemical assays, or clinical presentation confirmed by a physician. This code is appropriate when documentation specifies the "type C" variant of Niemann-Pick disease.

• Differentiate from other Niemann-Pick types (A, B, D) as they have distinct codes.
• Look for documentation of specific genetic mutations (e.g., in NPC1 or NPC2 genes) or characteristic clinical findings like hepatosplenomegaly, ataxia, dystonia, and cognitive decline.
• Code any associated neurological manifestations or organ involvement separately as secondary diagnoses.