Thelansis

  Acid sphingomyelinase (ASM) deficiency (ASMD), a rare lysosomal storage disease, is an autosomal recessive genetic disorder caused by mutations in the SMPD1 gene. ASMD has been classified as; Niemann-Pick disease type A (NPD A) and Niemann-Pick disease type B (NPD B).   More than 180 different SMPD1 mutations are identified in patients with ASMD, including missense, nonsense, frameshift mutations, and splice variants. Diagnoses incidence of ASMD at approximately 0.5 per 100,000 births. NPD A patients have a relatively uniform natural history characterized by severe progressive neurodegeneration in the first year and death typically by three years of age. NPD B has a variable disease course associated with a broad spectrum of disease severity and manifestations. Clinical manifestations of ASMD are hepatosplenomegaly, developmental delay, cherry-red maculae, interstitial lung disease, hyperlipidemia characterized by low high-density lipoprotein (HDL) cholesterol, and t...