This disease is extremely rare and is autosomal recessive. It is also known as Gunther's disease. The deficient enzyme is uroporphyrinogen III cosynthase (or uroporphyrinogen III synthase). Various mutations in the gene for this enzyme have been identified in different families. As is characteristic of the erythropoietic porphyrias, symptoms begin during infancy. Sometimes CEP is recognized as a cause of anemia in a fetus before birth. In less severe cases symptoms may begin during adult life. Porphyrins are markedly increased in bone marrow, red blood cells, plasma, urine and feces. Porphyrins are also deposited in the teeth and bones.
Skin photosensitivity may be extreme, and can lead to blistering, severe scarring and increased hair growth. Bacteria may infect the damaged skin. Facial features and fingers may be lost through phototoxic damage as well as infection. Red blood cells have a shortened life-span, and anemia often results. Synthesis of heme and hemoglobin are actually increased to compensate for the shortened red blood cell survival.
Treatment and Prognosis
Blood transfusions and perhaps removing the spleen may reduce porphyrin production by the bone marrow. Activated charcoal given by mouth is sometimes effective. Bone Marrow Transplantation has been very effective in some patients. Stem cell transplantation and gene therapy may also be an option in the future.