A 7-month-old boy presents with failure to thrive and pallor. Vital signs show HR 128/min, RR 22/min, Temp 37.2°C. Laboratory studies reveal hemoglobin 7.2 g/dL with megaloblastic anemia unresponsive to folate and vitamin B12 supplementation. Markedly elevated urinary orotic acid is noted, while serum ammonia remains normal at 18 μmol/L. The patient denies hepatomegaly on examination. Which of the following is the most appropriate treatment?
- A)Thiamine supplementation
- B)Restriction of dietary protein
- C)Allopurinol
- D)Uridine supplementationGABARITO
- E)Vitamin C supplementation
Explicação
This infant has hereditary orotic aciduria caused by deficiency of UMP synthase in de novo pyrimidine synthesis. Lack of pyrimidine production leads to megaloblastic anemia, and excess orotic acid appears in the urine without hyperammonemia. Uridine bypasses t... Ver explicação completa e trilha adaptativa →