A rare cause of fatal pulmonary alveolar proteinosis: Niemann-Pick disease type C2 and a novel mutation.

Niemann-Pick disease type C (NPC) is a fatal autosomal recessive lipid storage disease associated with impaired trafficking of unesterified cholesterol and glycolipids in lysosomes and late endosomes. This disease is commonly characterized by hepatosplenomegaly and severe progressive neurological dysfunction. There are two defective genes that cause this illness. One of these genes is NPC1 gene which is the cause of illness in 95% of the patients. The other gene is the rare type NPC2 which is the cause of illness in 5% of the patients. Patients with NPC2 usually present with respiratory distress in early infancy, which is rather unusual with NPC1. This article discusses about a patient who died at an early age from pulmonary involvement and who subsequently was found to have a novel homozygous mutation of NPC2 gene.