Porphyria

Overview, Causes, & Risk Factors

Porphyria is a condition that affects how heme is made and broken down by the body. Heme is the part of hemoglobin that carries oxygen to the cells of the body.

What is going on in the body?

Hemoglobin is the main oxygen-carrying component of blood. Porphyrins are compounds in the body that affect the way hemoglobin is made, stored, and used.

A person with porphyria makes and excretes excessive amounts of porphyrins. This often causes abnormally high levels of heme in the blood. There are several kinds of porphyria. Porphyrias are classified by where in the body the excess porphyrins are made. They include:

  • erythropoietic, with extra production in the bone marrow
  • hepatic, with extra production in the liver
  • erythrohepatic, with extra production in the bone marrow and liver

    • What are the causes and risks of the disease?

    Most cases of porphyria are caused by genetic disorders. Some cases are caused by toxic substances, such as ingestion or exposure to lead. Menstruation may increase symptoms in women.

    Symptoms & Signs

    What are the signs and symptoms of the disease?

    Symptoms vary, depending on the type of porphyria. Symptoms that may occur with most of the porphyrias include:

  • severe abdominal pain
  • chest pain
  • sensitivity to bright sunlight
  • muscle cramping and weakness
  • numbness and tingling of the legs and arms

    • Hepatic porphyria may cause these additional symptoms:

  • fever
  • vomiting
  • constipation
  • rapid heart beat
  • liver disease
  • psychiatric disturbances, such as depression or mania
  • leg pain
  • skin discoloration, itching, and blistering
  • changes in urine color to a red-brown
  • changes in tooth color

    • Diagnosis & Tests

    How is the disease diagnosed?

    The diagnosis of porphyria depends on the symptoms and what type of porphyria is suspected. Steps in diagnosis may include:

  • a medical history, and history of activity or trauma
  • a thorough medical exam
  • blood tests, including a complete blood count or CBC, which counts the number of each kind of cell in the blood
  • a blood test to measure porphyrins in the blood
  • stool tests and cultures to look for any blood, infection, or porphyrins in the stool
  • urine tests to check for porphyrins and lead in the urine

    • Prevention & Expectations

    What can be done to prevent the disease?

    Prevention of porphyria is not always possible. Avoiding things that trigger symptoms may decrease the risk of symptoms. These triggers include:

  • excessive bright sunlight
  • certain medications, such as oral contraceptives, alcohol, and barbiturates
    • Genetic counseling may be helpful to couples with a family history of porphyria.

    What are the long-term effects of the disease?

    A person with porphyria may have recurrent and severe symptoms. Some forms of porphyria may lead to gallstones or chronic skin or liver problems. Electrolyte or salt imbalances in the blood can occur. If untreated, porphyria may also lead to respiratory distress, shock, and death.

    What are the risks to others?

    Porphyria is not contagious. It can be passed genetically to offspring.

    Treatment & Monitoring

    What are the treatments for the disease?

    Treatment depends on the type of porphyria. Treatment of acute, or short term, intermittent porphyria includes intravenous fluids and glucose. Other treatments may include:

  • strong pain medications for abdominal pain.
  • hematin, an enzyme inhibitor that can help prevent or treat attacks
  • tranquilizers to reduce anxiety
  • medications such as beta-carotene to reduce light sensitivity and the effects of sunlight
  • a diet high in carbohydrates
  • surgery, such as a spleen removal to treat anemia

    • What are the side effects of the treatments?

    Pain medications may cause stomach upset, irritability, and drowsiness. Surgery poses a risk of bleeding, infection, and allergic reaction to anesthesia.

    What happens after treatment for the disease?

    A person with porphyria may have relapses, in which the condition worsens and symptoms return.

    How is the disease monitored?

    The person is monitored for relapses. Blood and urine tests may also be used to monitor the levels of porphyrins in the blood and urine. Further treatment will be given when symptoms or attacks occur. Any new or worsening symptoms should be reported to the healthcare provider.

    Attribution

    Author:Bill Harrison, MD
    Date Written:
    Editor:Duff, Ellen, BA
    Edit Date:10/09/00
    Reviewer:Eileen McLaughlin, RN, BSN
    Date Reviewed:07/05/01

    Sources

    Harrison's Principles of Internal Medicine, Fauci et al, 1998

    Complete Guide to Symptoms, Illness, and Surgery, Griffith, 2000

    Professional Guide to Diseases, Burlew et al, 1995