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X-linked sideroblastic anemia



Other Names:
Sideroblastic anemia X-linked; XLSA; Anemia sex-linked hypochromic sideroblastic; Sideroblastic anemia X-linked; XLSA; Anemia sex-linked hypochromic sideroblastic; ANH1; Congenital sideroblastic anemia; Erythroid 5-aminolevulinate synthase deficiency; Hereditary iron-loading anemia; X chromosome-linked sideroblastic anemia; Anemia hereditary sideroblastic See More
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X-linked sideroblastic anemia is an inherited disorder that prevents developing red blood cells (erythroblasts) from making enough hemoglobin. People with X-linked sideroblastic anemia have mature red blood cells that are smaller than normal (microcytic) and appear pale (hypochromic) because of the shortage of hemoglobin. This disorder also leads to an abnormal accumulation of iron in red blood cells. The iron-loaded erythroblasts, which are present in bone marrow, are called ring sideroblasts. These abnormal cells give the condition its name. The signs and symptoms of X-linked sideroblastic anemia result from a combination of reduced hemoglobin and an overload of iron. They range from mild to severe and most often appear in young adulthood. Common features include fatigue, dizziness, a rapid heartbeat, pale skin, and an enlarged liver and spleen (hepatosplenomegaly). Over time, severe medical problems such as heart disease and liver damage (cirrhosis) can result from the buildup of excess iron in these organs. X-linked sideroblastic anemia is caused by mutation in the ALAS2 gene. In rare cases, mutations are found in both the HFE gene and the ALAS2 gene, resulting in a more severe form of X-linked sideroblastic anemia. X-linked sideroblastic anemia is inherited in an X-linked recessive pattern.[1]
Last updated: 3/11/2013

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.

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Medical Terms Other Names
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HPO ID
80%-99% of people have these symptoms
Abnormality of iron homeostasis 0011031
Anemia
Low number of red blood cells or hemoglobin
0001903
Dilated cardiomyopathy
Stretched and thinned heart muscle
0001644
Fatigue
Tired
Tiredness
[ more ]
0012378
Muscle weakness
Muscular weakness
0001324
Pallor 0000980
30%-79% of people have these symptoms
Atrial fibrillation
Quivering upper heart chambers resulting in irregular heartbeat
0005110
Left ventricular dysfunction 0005162
Lipodystrophy
Inability to make and keep healthy fat tissue
0009125
Sudden cardiac death
Premature sudden cardiac death
0001645
Syncope
Fainting spell
0001279
5%-29% of people have these symptoms
Abnormal lymphocyte physiology 0031409
Atrial flutter 0004749
Congestive heart failure
Cardiac failure
Cardiac failures
Heart failure
[ more ]
0001635
Dyspnea
Trouble breathing
0002094
Elevated hepatic transaminase
High liver enzymes
0002910
Glucose intolerance 0001952
Hyperpigmentation of the skin
Patchy darkened skin
0000953
Muscular dystrophy 0003560
Pericardial effusion
Fluid around heart
0001698
Sinoatrial block 0012723
Splenomegaly
Increased spleen size
0001744
Supraventricular tachycardia 0004755
Ventricular arrhythmia 0004308
Percent of people who have these symptoms is not available through HPO
Hypochromic microcytic anemia 0004840
Macrocytic anemia 0001972
Sideroblastic anemia 0001924
Variable expressivity 0003828
X-linked recessive inheritance 0001419
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Last updated: 7/1/2020

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


Related diseases are conditions that have similar signs and symptoms. A health care provider may consider these conditions in the table below when making a diagnosis. Please note that the table may not include all the possible conditions related to this disease.

Conditions with similar signs and symptoms from Orphanet
The differential diagnosis should include other types of inherited sideroblastic anemia and in case of macrocytic red cells in females also acquired myelodysplasia (refractory anemia with ringed sideroblasts or RARS (see these terms). Most female carriers show some evidence of microcytic, hypochromic red blood cells but hematological parameters cannot be relied upon for genetic counseling purposes and DNA analysis is required
Visit the Orphanet disease page for more information.

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

In-Depth Information

  • 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 X-linked sideroblastic anemia. Click on the link to view a sample search on this topic.

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  1. X-linked sideroblastic anemia. Genetics Home Reference (GHR). April 2009; http://ghr.nlm.nih.gov/condition/x-linked-sideroblastic-anemia. Accessed 3/11/2013.