KROK 1 2014 – Question 71 · KROK (Medicine) · Biological Chemistry
A patient with hereditary hyperammonemia due to a disorder of ornithine cycle has developed secondary orotaciduria. The increased synthesis of orotic acid is caused by an increase in the following metabolite of ornithine cycle:
- A. Urea
- B. Argininosuccinate
- C. Carbamoyl phosphate
- D. Citrulline
- E. Ornithine
Hint
Orotic acid belongs to pyrimidine synthesis, so ask which early mitochondrial compound feeds both the urea cycle and that pathway and would spill over when the cycle stalls.
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