Niemann-Pick disease type A
Findings
No curated finding names Niemann-Pick disease type A yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
Niemann-Pick disease type A is a very severe subtype of Niemann-Pick disease, an autosomal recessive lysosomal disease, and is characterized clinically by onset in infancy or early childhood with failure to thrive, hepatosplenomegaly, and rapidly progressive neurodegenerative disorders.
Definition from the Mondo Disease Ontology (MONDO:0009756), read 2026-09-29. CC BY 4.0.
- Onset and course
- Infantile onset
HPO, annotations 2026-09-02
Features
40 features
What the disease is reported to present with, and how often among people who have it — never how often a feature means the disease. HPO, annotations 2026-09-02.
- Cherry red spot of the maculaHPOHP:0010729
- 10 of 10 reported patients
- Frequent (30% to 79% of cases)
- Decreased acid sphingomyelinase activityHPOHP:0034300
- Obligate (100% of cases)
- Delayed CNS myelinationHPOHP:0002188
- 3 of 3 reported patients
- Developmental regressionHPOHP:0002376
- 10 of 10 reported patients
- Elevated circulating alanine aminotransferase concentrationHPOHP:0031964
- 10 of 10 reported patients
- Elevated circulating aspartate aminotransferase concentrationHPOHP:0031956
- 10 of 10 reported patients
Show the remaining 28
- Skeletal muscle atrophyHPOHP:0003202
- 10 of 10 reported patients
- Abnormal pulmonary interstitial morphologyHPOHP:0006530
- Very frequent (80% to 99% of cases)
- Elevated circulating hepatic transaminase concentrationHPOHP:0002910
- Very frequent (80% to 99% of cases)
- Elevated tissue sphingomyelin concentrationHPOHP:6000292
- Very frequent (80% to 99% of cases)
- Failure to thrive in infancyHPOHP:0001531
- Very frequent (80% to 99% of cases)
- HepatosplenomegalyHPOHP:0001433
Genes
1 gene
Germline variants in the gene encoding each protein, as classified by GenCC submitters, each in their own words. Limited, disputed and refuted submissions are listed too.
- SMPD1HGNC:11120
- Definitive · G2P · Autosomal recessive · 2017
- Strong · Genomics England PanelApp · Autosomal recessive · 2020
- Strong · PanelApp Australia · Autosomal recessive · 2025
- Supportive · Orphanet · Autosomal recessive · 2021