Gunther disease, also known as congenital erythropoietic porphyria (CEP), uroporphyrinogen III synthase deficiency and UROS deficiency, is a congenital form of erythropoietic porphyria. The word porphyria originated from the Greek word porphura. Porphura actually means “purple pigment”, which, in suggestion, the color that the body fluid changes when a person has Gunther’s disease. It is a rare, autosomal recessive metabolic disorder affecting heme, caused by deficiency of the enzyme uroporphyrinogen cosynthetase. It is extremely rare, with a prevalence estimated at 1 in 1,000,000 or less. There have been times that prior to birth of a fetus, Gunther's disease has been shown to lead to anemia. In milder cases patients have not presented any symptoms until they have reached adulthood. In Gunther's disease, porphyrins are accumulated in the teeth and bones and an increased amount are seen in the plasma, bone marrow, feces, red blood cells, and urine.