"Excessive excretion of orotic acid in the urine; specifically a genetic (autosomal recessive) disorder of pyrimidine metabolism in humans, in which deficient activity of the enzyme uridine monophosphate synthase, which catalyses the two-step conversion of orotic acid to uridine monophosphate, results in the accumulation of orotic acid and in megaloblastic anaemia that responds to uridine administration", 1950s; earliest use found in Journal of Clinical Investigation. From orotic acid + -uria.[orotic aciduria etymology, orotic aciduria origin, 英语词源]