National Center for Advancing and Translational Sciences Genetic and Rare Diseases Information Center, a program of the National Center for Advancing and Translational Sciences

Sitosterolemia


Other Names:
Retention of dietary cholesterol and abnormal retention of non-cholesterol sterols in the body; Phytosterolemia; Plant sterol storage disease
Categories:
Sitosterolemia is a rare inherited condition in which plant sterols accumulate in the blood and tissues. Plant sterols, including sitosterol, stigmasterol, and campesterol, are fatty substances found in vegetable oils and nuts. Individuals with sitosterolemia have extremely high levels of sitosterol (30 to 100 times higher than normal), along with mildly to moderately elevated levels of cholesterol in their blood. These plant sterols and cholesterol build up in the arteries, leading to premature thickening of the artery walls and early heart disease. Affected individuals may also develop small yellowish growths called xanthomas on or under the skin and in the tendons.[1][2] Sitosterolemia is caused by mutations in the ABCG5 or ABCG8 gene. The condition is inherited in an autosomal recessive pattern.[1][2][3] Treatment involves restricting foods that are high in plant and shellfish sterols, and taking medications that decrease the concentration of these products in the blood.[2][3]
Last updated: 4/12/2016

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Showing of 17 |
Medical Terms Other Names
Learn More:
HPO ID
Percent of people who have these symptoms is not available through HPO
Abdominal pain
Pain in stomach
Stomach pain
[ more ] 		0002027
Abnormal bleeding
Bleeding tendency
0001892
Abnormality of the liver
Abnormal liver
Liver abnormality
[ more ] 		0001392
Arthralgia
Joint pain
0002829
Arthritis
Joint inflammation
0001369
Autosomal recessive inheritance 0000007
Chronic hemolytic anemia 0004870
Coronary artery atherosclerosis
Plaque build-up in arteries supplying blood to heart
0001677
Episodic hemolytic anemia 0004802
Giant platelets 0001902
Hyperapobetalipoproteinemia 0008158
Hypercholesterolemia
Elevated serum cholesterol
Elevated total cholesterol
Increased total cholesterol
[ more ] 		0003124
Impaired platelet aggregation 0003540
Reticulocytosis
Increased immature red blood cells
Increased number of immature red blood cells
[ more ] 		0001923
Splenomegaly
Increased spleen size
0001744
Stomatocytosis 0004446
Tuberous xanthoma 0031290
Showing of 17 |
Last updated: 7/1/2020
Sitosterolemia is diagnosed by measuring the levels of plant sterols in the blood, including sitosterol, campesterol, and stigmasterol. Normal cholesterol studies will not diagnosed sitosterolemia because they cannot distinguish among the different sterols. DNA analysis of the ABCG5 and ABCG8 genes can be helpful in detecting mutations and confirming the diagnosis.[2][3]
Last updated: 4/12/2016

Testing Resources

  • The Genetic Testing Registry (GTR) provides information about the genetic tests for this condition. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.
The primary goal of treatment is to reduce the concentration of plant sterols in the blood (to below 1 mg/dl, if possible). Sitosterolemia can be managed by restricting floods that have a high concentration of plant and shellfish sterols, and with the use of medications. Foods with high plant sterols include vegetable oils, margarine, nuts, seeds, avocados, and chocolate. The drug ezetimibe may be used to decrease the plant sterol concentration in blood. Cholestyramine has also been used in some individuals.[2][3] If medications don't work, partial ileal bypass surgery may be considered.[3]

GeneReviews offers additional details about management.
Last updated: 4/12/2016

If you need medical advice, you can look for doctors or other healthcare professionals who have experience with this disease. You may find these specialists through advocacy organizations, clinical trials, or articles published in medical journals. You may also want to contact a university or tertiary medical center in your area, because these centers tend to see more complex cases and have the latest technology and treatments.

If you can’t find a specialist in your local area, try contacting national or international specialists. They may be able to refer you to someone they know through conferences or research efforts. Some specialists may be willing to consult with you or your local doctors over the phone or by email if you can't travel to them for care.

You can find more tips in our guide, How to Find a Disease Specialist. We also encourage you to explore the rest of this page to find resources that can help you find specialists.

Healthcare Resources

Research helps us better understand diseases and can lead to advances in diagnosis and treatment. This section provides resources to help you learn about medical research and ways to get involved.

Clinical Research Resources

  • ClinicalTrials.gov lists trials that are related to Sitosterolemia. Click on the link to go to ClinicalTrials.gov to read descriptions of these studies.

    Please note: Studies listed on the ClinicalTrials.gov website are listed for informational purposes only; being listed does not reflect an endorsement by GARD or the NIH. We strongly recommend that you talk with a trusted healthcare provider before choosing to participate in any clinical study.

Patient Registry

Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

Organizations Supporting this Disease

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

  • Genetics Home Reference contains information on Sitosterolemia. This website is maintained by the National Library of Medicine.

In-Depth Information

  • GeneReviews provides current, expert-authored, peer-reviewed, full-text articles describing the application of genetic testing to the diagnosis, management, and genetic counseling of patients with specific inherited conditions.
  • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Sitosterolemia. Click on the link to view a sample search on this topic.

Questions sent to GARD may be posted here if the information could be helpful to others. We remove all identifying information when posting a question to protect your privacy. If you do not want your question posted, please let us know.

  1. Sitosterolemia. Genetics Home Reference (GHR). May 2013; https://ghr.nlm.nih.gov/condition/sitosterolemia.
  2. What is Sitosterolemia?. Sterol & Isoprenoid Research Consortium. 2016; http://www.rarediseasesnetwork.org/cms/stair/Learn-More/Disorder-Definitions.
  3. Merkens LS, Myrie SB, Steiner RD, Mymin D. Sitosterolemia. GeneReviews. April 4, 2013; http://www.ncbi.nlm.nih.gov/books/NBK131810/.