A rare metabolic disorder where an inherited enzyme deficiency (lack of orotidylic pyrophosphorylase and orotidylic decarboxylase or a lack of orotidylic decarboxylase only) impairs the body\'s ability to break down orotic acid which then builds up in the body and causes damage.
Orotic aciduria hereditary
Its hereditary form, an autosomal recessive disorder, can be caused by a deficiency in the enzyme UMPS, a bifunctional protein that includes the enzyme activities of orotate phosphoribosyltransferase and orotidine 5\'-phosphate decarboxylase. Orotic aciduria has an autosomal recessive of inheritance.
It can also arise secondary to blockage of the urea cycle, particularly ornithine transcarbamylase deficiency.
Administration of cytidine monophosphate and uridine monophosphate reduces urinary orotic acid and the anemia.
Administration of uridine, which is converted to UMP, will bypass the metabolic block and provide the body with a source of pyrimidine.