Definition Porphyria is a condition that affects how haeme is made and broken down by the body. Haeme is the part of haemoglobin that carries oxygen to the cells of the body.
What is going on in the body? Haemoglobin is the main oxygen-carrying component of blood. Porphyrins are compounds in the body that affect the way haemoglobin is made, stored, and used.
A person with porphyria makes and excretes excessive amounts of porphyrins. This often causes abnormally high levels of haeme 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 signs and symptoms of the disease? Symptoms vary, depending on the type of porphyria. Symptoms that may occur with most of the porphyrias include:
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.
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:
Genetic counselling may be helpful to couples with a family history of porphyria.
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 examination
blood tests, including a full blood count or FBC, 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
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.
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:
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 doctor.
Author: Bill Harrison, MD Reviewer: HealthAnswers Australia Medical Review Panel Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia Last Updated: 1/10/2001 Contributors Potential conflict of interest information for reviewers available on request