The porphyrias are a group of inherited disorders in which there is only one normal gene to produce a key enzyme in the biosynthesis of chelated iron or heme. With only one normal gene, there is a reduced level of normal enzyme activity, resulting in a buildup of the precursors behind the deficient enzyme. This buildup accumulates in body fluids and tissues and results in toxicity. Each type of porphyria involves different enzymes. Depending on the enzyme involved, the clinical manifestations of porphyria differ. In congenital erythropoietic porphyria or Gunther’s disease, the enzyme involved is uroporphyrinogen III cosynthase (UROS). Although no prevalence rate is reported, congenital porphyria is relatively rare and may be underdiagnosed unless it is symptomatic.
A rare condition inherited as an autosomal recessive trait. It is characterized by severe skin lesions, hemolytic anemia, and splenomegaly.