Sitosterolemia familial E78.4

Sitosterolemia (phytosterolemia) is a very rare, autosomal recessive inherited sterol storage disorder characterized by markedly elevated plasma levels of plant sterols. The clinical features of sitosterolemia are xanthomas, premature atherosclerosis, arthritis, and occasionally liver dysfunction and hematologic abnormalities.

Mutation in the ABCG8 or ABCG5 gene at gene locus 2p21

From preschool age, xanthomas and atherosclerosis develop with increased risk of myocardial infarction.

• Xanthomas (tendon xanthomas, xanthelasma)
• Arteriosclerosis with increased risk of myocardial infarction
• Splenomegaly
• Arthralgias and arthritides
• Specific hematologic problems such as thrombocytopenia, hemolytic anemia, and splenomegaly are common (Wang Z et al. 2014).

Clinical picture with tendon xanthomas and xanthelasma. Diagnosis is made by detection of elevated phytosterols in plasma and by molecular genetics.

Phytosterol-reduced diet, anion exchangers (ion exchangers).

1. Bain BJ et al (2016) Phytosterolemia. Am J Hematol 91:643.
2. Shen MF et al. (2022) Clinical and Genetic Analysis of a Family With Sitosterolemia Caused by a Novel ATP-Binding Cassette Subfamily G Member 5 Compound Heterozygous Mutation. Front Cardiovasc Med 9:887618.
3. Wang Z et al (2014) Specific macrothrombocytopenia/hemolytic anemia associated with sitosterolemia. Am J Hematol 89:320-324.