[Congenital erythropoietic porphyria : An update]

Congenital erythropoetic porphria is a very rare type of autosomal recessive nonacute porphyria. Homozygous or compound heterozygous mutations in the uroporphyrinogen III consynthase gene cause a marked enzymatic deficiency of uroporphyrinogen III consynthase, the fourth enzyme along the heme biosynthetic pathway.

Clinically, affected patients are characterized by a moderate to severe photosensitivity. Starting early in infancy, they develop blisters, erosions, and exulcerations in sun-exposed areas of the body, often resulting in scar formation and mutilation. Besides the cutaneous changes, hemolytic anemia, transfusion-dependent pancytopenia, hepatosplenomegaly and liver cirrhosis can occur. Due to increased susceptibility for infections and because of the hematological and hepatic complications, affected individuals have a decreased life expectancy, rarely exceeding 40 years of age.

Currently, no causal treatment is available for the disorder. Therefore, the most important therapeutic modality is strict avoidance of sunlight, preferably by inversion of the day-night rhythm, or at least consequent photoprotection with adequate clothing. In severe cases, bone marrow or stem cell transplantation should be considered.