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    Paroxysmal Nocturnal Hemoglobinuria

    Important
    It is possible that the main title of the report Paroxysmal Nocturnal Hemoglobinuria is not the name you expected. Please check the synonyms listing to find the alternate name(s) and disorder subdivision(s) covered by this report.

    Synonyms

    • PNH
    • Marchiafava-Micheli syndrome

    Disorder Subdivisions

    • None

    General Discussion

    Paroxysmal nocturnal hemoglobinuria (PNH) is a rare disorder in which red blood cells break apart prematurely. It is an acquired hematopoietic stem cell disorder. Hematopoietic stem cells are created in the bone marrow, the spongy center of the long bones of the body. These cells grow and eventually develop into red blood cells, white blood cells and platelets. Some hematopoietic stem cells in individuals with PNH are defective and consequently develop into defective blood cells. These defective blood cells, especially red blood cells, are extremely susceptible to premature destruction by a person's own immune system.

    The classic finding is the premature destruction of red blood cells (hemolysis), resulting in repeated episodes of hemoglobin in the urine (hemoglobinuria). Hemoglobin is the red, iron-rich, oxygen-containing pigment of the blood. Individuals with hemoglobinuria may exhibit dark-colored or bloody urine. This finding is most prominent in the morning, after the urine has concentrated overnight during sleep. However, hemolysis in individuals with PNH is a constant process, it does not occur only at night. Blood in the urine may not always be visible to the eye.

    In addition to hemolysis, individuals with PNH are also susceptible to developing repeated, potentially life-threatening blood clots (thromboses). Affected individuals also have some degree of underlying bone marrow dysfunction. Severe bone marrow dysfunction potentially results in low levels of red and white blood cells and platelets (pancytopenia). The specific symptoms of PNH vary greatly from one person to another and affected individuals usually do not exhibit all of the symptoms potentially associated with the disorder.

    Resources

    Aplastic Anemia & MDS International Foundation, Inc.
    100 Park Avenue, Suite 108
    Rockville, MD 20850
    USA
    Tel: (301)279-7202
    Fax: (301)279-7205
    Tel: (800)747-2820
    Email: help@aamds.org
    Internet: http://www.aamds.org

    NIH/National Heart, Lung and Blood Institute ~ Hematology Branch
    10 Center Dr, Building 10-CRC
    3-5140, MSC-1202
    Bethesda, MD 20892-1202
    Tel: (301)496-5093
    Fax: (301)496-8396
    Tel: (800)644-2337
    Email: YoungNS@mail.nih.gov
    Internet: http://dir.nhlbi.nih.gov/labs/hb/index.asp?

    PNH Support Group
    http://www.pnhdisease.org
    Internet: http://www.pnhdisease.org/

    Genetic and Rare Diseases (GARD) Information Center
    PO Box 8126
    Gaithersburg, MD 20898-8126
    Tel: (301)251-4925
    Fax: (301)251-4911
    Tel: (888)205-2311
    TDD: (888)205-3223
    Internet: http://rarediseases.info.nih.gov/GARD/

    Madisons Foundation
    PO Box 241956
    Los Angeles, CA 90024
    Tel: (310)264-0826
    Fax: (310)264-4766
    Email: getinfo@madisonsfoundation.org
    Internet: http://www.madisonsfoundation.org

    PNH Research and Support Foundation
    PO Box 10983
    Rockville, MD 20849
    Tel: (888)582-9993
    Fax: (888)582-9993
    Tel: (888)582-9993
    Email: info@pnhfoundation.org
    Internet: http://www.pnhfoundation.org

    For a Complete Report:

    This is an abstract of a report from the National Organization for Rare Disorders (NORD). A copy of the complete report can be downloaded free from the NORD website for registered users. The complete report contains additional information including symptoms, causes, affected population, related disorders, standard and investigational therapies (if available), and references from medical literature. For a full-text version of this topic, go to www.rarediseases.org and click on Rare Disease Database under "Rare Disease Information".

    The information provided in this report is not intended for diagnostic purposes. It is provided for informational purposes only. NORD recommends that affected individuals seek the advice or counsel of their own personal physicians.

    It is possible that the title of this topic is not the name you selected. Please check the Synonyms listing to find the alternate name(s) and Disorder Subdivision(s) covered by this report

    This disease entry is based upon medical information available through the date at the end of the topic. Since NORD's resources are limited, it is not possible to keep every entry in the Rare Disease Database completely current and accurate. Please check with the agencies listed in the Resources section for the most current information about this disorder.

    For additional information and assistance about rare disorders, please contact the National Organization for Rare Disorders at P.O. Box 1968, Danbury, CT 06813-1968; phone (203) 744-0100; web site www.rarediseases.org or email orphan@rarediseases.org

    Last Updated: 1/13/2011
    Copyright 1989, 1994, 1996, 1997, 2003, 2004, 2005, 2007, 2011 National Organization for Rare Disorders, Inc.

    WebMD Medical Reference from the National Organization for Rare Disorders

    Last Updated: May 28, 2015
    This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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