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Paroxysmal nocturnal hemoglobinuria

Other Names for this Disease
  • Marchiafava-Micheli disease
  • PNH
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Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired disorder that leads to the premature death and impaired production of blood cells. It can occur at any age, but is usually diagnosed in young adulthood. People with PNH have recurring episodes of symptoms due to hemolysis, which may be triggered by stresses on the body such as infections or physical exertion. This results in a deficiency of various types of blood cells and can cause signs and symptoms such as fatigue, weakness, abnormally pale skin (pallor), shortness of breath, and an increased heart rate. People with PNH may also be prone to infections and abnormal blood clotting (thrombosis) or hemorrhage, and are at increased risk of developing leukemia. It is caused by acquired, rather than inherited, mutations in the PIGA gene; the condition is not passed down to children of affected individuals. Sometimes, people who have been treated for aplastic anemia may develop PNH.[1] The treatment of PNH is largely based on symptoms; stem cell transplantation is typically reserved for severe cases of PNH with aplastic anemia or those whose develop leukemia.[2]
Last updated: 1/15/2011


  1. Paroxysmal nocturnal hemoglobinuria. Genetics Home Reference. May 2007; Accessed 1/15/2011.
  2. Emmanuel C Besa and Ulrich Woermann. Paroxysmal Nocturnal Hemoglobinuria. eMedicine. March 27, 2009; Accessed 1/15/2011.
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  • Genetics Home Reference (GHR) contains information on Paroxysmal nocturnal hemoglobinuria. This website is maintained by the National Library of Medicine.
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  • The National Organization for Rare Disorders (NORD) is a federation of more than 130 nonprofit voluntary health organizations serving people with rare disorders. Click on the link to view information on this topic.

In Depth Information

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  • The Online Mendelian Inheritance in Man (OMIM) is an 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 Paroxysmal nocturnal hemoglobinuria. Click on the link to view a sample search on this topic.