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Congenital Erythropoietic Porphyria (CEP)

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CEP is very rare and caused by changes in the URO gene which results in low levels of the UROS enzyme in the heme pathway. Porphyrins accumulate, particularly in the skin, bone marrow, teeth, and bones. The major symptoms are sensitivity of the skin to sunlight and some types of artificial light, and anemia which can be very severe.


After exposure to sunlight, the photo-activated porphyrins in the skin cause blistering. The fluid-filled blisters rupture and get infected. These wound infected can lead to scarring, bone loss, and deformities. The hands, arms, and face are the most commonly affected areas. Increased hair growth (hypertrichosis) on sun-exposed skin, brownish-colored teeth (erythrodontia), and reddish-colored urine are common. There may be bone fragility and vitamin deficiencies, especially vitamin D. The spleen can be enlarged, particularly in people with anemia.


In people with severe anemia repeated red blood cell transfusions are needed. In severely affected people who are dependent on blood transfusions, a bone marrow transplant may be needed. People who have successful bone marrow transplants no longer have sun-sensitivity.


People with CEP should see a porphyria specialist at least once a year for regular follow-up. People who have severe anemia may need to see a specialist more regularly.

Avoiding exposure to sunlight is the most important way to manage symptoms for people with CEP. People with CEP need to wear protective clothing, and have windows tinted in their cars and homes.


CEP is inherited as an autosomal recessive genetic disorder. Recessive disorders occur when an individual inherits two copies of an abnormal gene for the same trait or disease, one from each parent. Typically, there is no family history of the disease (except possibly in siblings), and neither parent has symptoms, but each carries a changed gene that they can pass to their children. The risk for two carrier parents to both pass the changed gene and have an affected child is 25% with each pregnancy. If an individual receives one normal gene and one changed gene, the person will be a carrier for the disease, and will not have any symptoms.

Inheritance - CEP