Erythropoietic Protoporphyria - Symptoms & Treatment
Erythropoietic protoporphyria (EPP) is a genetic disorder arising from impaired activity of ferrochelatase, the ultimate enzyme of heme biosynthesis. Porphyrins are chemicals that are important for manufacturing blood and enzymes within the body. EPP is due to an inherited deficiency of the enzyme ferrochelatase. First symptoms usually appear in infancy or early childhood and present as an uncomfortable or painful burning sensation of the skin after sun exposure. Symptoms usually start in childhood. It occurs most often on the tops of the hands and feet, face and ears. In the case of EPP, there is a build up of one of these porphyrins (protoporphyrin) in the blood, especially in the red blood cells. This leads to a sensitivity to sunlight. Many different mutations of the ferrochelatase gene have been found in various EPP families. Protoporphyrin accumulates in the bone marrow, red blood cells and sometimes the liver. Accumulation of protoporphyrins in the liver can cause liver damage. Protoporphyrins in the bile can lead to bile stones. Pain and swelling develop soon after the skin is exposed to sunlight. Because blistering and scarring seldom occur, doctors do not always recognize the disorder.
Erythropoietic protoporphyria is one of a group of disorders known as the porphyrias. People with EPP-induced liver disease usually have mild changes in liver blood tests. In protoporphyria, a hereditary enzyme defect results in too much of a chemical (protoporphyrin) being present in the circulation and the skin. The predominant genotype associated with phenotypic expression is a mutant ferrochelatase allele encoding a defective protein with little or no function coupled with a normal variant allele with low gene expression. A very small number of people who have had with EPP for many years may develop liver damage. Fortunately this is rare. However, blistering and scarring is less common than in other types of "cutaneous" porphyria. Skin manifestations generally begin during childhood. They are more severe in the summer and can recur throughout life. Some people with erythropoietic protoporphyria may also have complications related to liver and gallbladder function.There is no cure for this disorder; however, symptoms can usually be managed by the simple expedient of limiting sun exposure.
Causes of Erythropoietic protoporphyria
The common causes and risk factor's of Erythropoietic protoporphyria include the following:
- Autosomal recessive inheritance of genes that encode abnormal uroporphyrinogen III synthase enzyme protein.
- A combination of factors.
- Exposure to sunlight.
Symptoms of Erythropoietic protoporphyria
Some sign and symptoms related to Erythropoietic protoporphyria are as follows:
- An uncomfortable or painful burning sensation of the skin after sun exposure.
- Hypersensitivity of the skin to sunlight.
- The affected skin may become red and swollen and blistered.
- Some types of artificial light, such as fluorescent lights (photosensitivity).
- Complications related to liver and gallbladder function.
- Personality change.
- Crampy abdominal pain (may be extremely severe).
Treatment of Erythropoietic protoporphyria
Here is list of the methods for treating Erythropoietic protoporphyria:
- Oral beta-carotene (a food precursor of vitamin A found naturally in tomatoes and carrots) is thought to help reduce photosensitivity in some people.
- Narrowband UVB phototherapy increases melanin content and induces skin thickening so may reduce sun sensitivity.
- Pain medication can be used.
- The use of oral alpha-tocopherol and ascorbic acid to quench reactive oxygen radicals has been advocated to reduce porphyrin-sensitized photodamage to skin elements and circulating erythrocytes.
- People who develop gallstones that contain protoporphyrin may need to have them surgically removed.
- Cysteine 500mg twice daily reduces photosensitivity.