Porphyria
Porphyria is a group of different disorders caused by abnormalities in the chemical steps leading to the production of heme, a substance that is important in the body. The largest amounts of heme are in the blood and bone marrow, where it carries oxygen. Heme is also found in the liver and other tissues.
Multiple enzymes are needed for the body to produce heme. If any one of the enzymes is abnormal, the process cannot continue and the intermediate products, porphyrin or its precursors, may build up and be excreted in the urine and stool.
The porphyria disorders can be grouped by symptoms—whether they affect the skin or the nervous system. The cutaneous porphyrias affect the skin. People with cutaneous porphyria develop blisters, itching, and swelling of their skin when it is exposed to sunlight. The acute porphyrias affect the nervous system. Symptoms of acute porphyria include pain in the chest, abdomen, limbs, or back; muscle numbness, tingling, paralysis, or cramping; vomiting; constipation; and personality changes or mental disorders. These symptoms appear intermittently.
The porphyrias are inherited conditions, and the genes for all enzymes in the heme pathway have been identified. Some forms of porphyria result from inheriting an abnormal gene from one parent (autosomal dominant). Other forms are from inheriting an abnormal gene from each parent (autosomal recessive). The risk that individuals in an affected family will have the disease or transmit it to their children is quite different depending on the type.
Attacks of porphyria can develop over hours or days and last for days or weeks. Porphyria can be triggered by drugs (barbiturates, tranquilizers, birth control pills, sedatives), chemicals, fasting, smoking, drinking alcohol, infections, emotional and physical stress, menstrual hormones, and exposure to the sun.
Porphyria is diagnosed through blood, urine, and stool tests. Diagnosis may be difficult because the range of symptoms is common to many disorders and interpretation of the tests may be complex. Each form of porphyria is treated differently. Treatment may involve treating with heme, giving medicines to relieve the symptoms, or drawing blood. People who have severe attacks may need to be hospitalized.
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For More Information
American Porphyria Foundation
P.O. Box 22712
Houston, TX 77227
Phone: 713–266–9617
Email: porphyrus@aol.com
Internet: www.porphyriafoundation.com
National Organization for Rare Disorders Inc. (NORD)
55 Kenosia Avenue
P.O. Box 1968
Danbury, CT 06813–1968
Phone: 1–800–999–6673 or 203–744–0100
Fax: 203–798–2291
Email: orphan@rarediseases.org
Internet: www.rarediseases.org
American Liver Foundation (ALF)
75 Maiden Lane, Suite 603
New York, NY 10038–4810
Phone: 1–800–GO–LIVER (465–4837),
1–888–4HEP–USA (443–7872),
or 212–668–1000
Fax: 212–483–8179
Email: info@liverfoundation.org
Internet: www.liverfoundation.org
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Additional Information on Porphyria
The National Digestive Diseases Information Clearinghouse collects resource information on digestive diseases for National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) Reference Collection. This database provides titles, abstracts, and availability information for health information and health education resources. The NIDDK Reference Collection is a service of the National Institutes of Health.
To provide you with the most up-to-date resources, information specialists at the clearinghouse created an automatic search of the NIDDK Reference Collection. To obtain this information, you may view the results of the automatic search on Porphyria.
If you wish to perform your own search of the database, you may access and search the NIDDK Reference Collection database online.
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National Digestive Diseases Information Clearinghouse
2 Information Way
Bethesda, MD 20892–3570
Phone: 1–800–891–5389
Fax: 703–738–4929
Email: nddic@info.niddk.nih.gov
Internet: www.digestive.niddk.nih.gov
The National Digestive Diseases Information Clearinghouse (NDDIC) is a service of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). The NIDDK is part of the National Institutes of Health of the U.S. Department of Health and Human Services. Established in 1980, the Clearinghouse provides information about digestive diseases to people with digestive disorders and to their families, health care professionals, and the public. The NDDIC answers inquiries, develops and distributes publications, and works closely with professional and patient organizations and Government agencies to coordinate resources about digestive diseases.
Publications produced by the Clearinghouse are carefully reviewed by both NIDDK scientists and outside experts.
This publication is not copyrighted. The Clearinghouse encourages users of this publication to duplicate and distribute as many copies as desired.
NIH Publication No. 03–4632
March 2003
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