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Pyrimidine Metabolism Disorders


Matt Demczko

, MD, Mitochondrial Medicine, Children's Hospital of Philadelphia

Reviewed/Revised Oct 2021 | Modified Sep 2022
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Pyrimidines may be synthesized de novo or recycled by a salvage pathway from normal catabolism. The catabolism of pyrimidines produces citric acid cycle intermediates. There are several disorders of pyrimidine metabolism (see the table Pyrimidine Metabolism Disorders Pyrimidine Metabolism Disorders ).


Uridine monophosphate synthase deficiency (hereditary orotic aciduria)

Uridine monophosphate is the enzyme that catalyzes orotate phosphoribosyltransferase and orotidine-5-monophosphate decarboxylase reactions. With deficiency, orotic acid accumulates, causing clinical manifestations of megaloblastic anemia, orotic crystalluria and nephropathy, cardiac malformations, strabismus, and recurrent infections.

Treatment of uridine monophosphate synthase deficiency is with oral uridine supplementation.

More Information

The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

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