Urea Cycle Disorders – Board-Style Questions

What this deck covers

urea cycle disorders in 18 board-style clinical cases with worked explanations. Each case gives you a clinical vignette, four options, the correct answer, and an explanation of why each of the other three is wrong, with the guideline or textbook it follows named on the answer.

Board-style teaching questions for paediatricians and trainees preparing for paediatric board, MRCPCH and licensing examinations. Written from published guidelines and standard paediatric textbooks, with the source named on every answer.

The 18 cases, in order

1. Day three, breathing fast
2. The gas nobody expected
3. Which step is blocked
4. Two generations
5. Another way out
6. The missing product
7. Faster than a drip
8. What goes in the bag
9. A new drug, a new problem
10. The teenager who stopped eating meat
11. Eating for years
12. A supplement for the long run
13. What the parents ask next
14. The well parent
15. Four days on from the birth
16. High, then better by itself
17. The early warning
18. Hair that breaks

Diagnoses and management options tested

Across the 18 cases you are asked to choose between options such as: A duct-dependent cardiac lesion, An alkalosis produced by overbreathing, Carbamoyl phosphate synthetase deficiency, It is mitochondrial, passed on by mothers, Sodium benzoate with sodium phenylbutyrate, It neutralises the acid the drugs generate, An exchange transfusion through an umbilical venous line, Half maintenance fluid, to limit the daily nitrogen load, The antiseizure drug added three weeks ago, Cyclical vomiting related to her migraines, An ordinary diet with extra fluid at every meal, Glycine, to assist conjugation by the drugs, How long he was comatose before treatment began, Reassurance only, as she has no symptoms.

Clinical pearls from this deck

• Fast breathing with clear lungs in a newborn: check the ammonia.
• Alkalotic sick newborn: nitrogen, not sepsis.
• Orotic acid up, citrulline down: the transcarbamylase step.
• Meat-avoiding mother, dying newborn boy: think X-linked.
• Benzoate and phenylbutyrate take nitrogen out the side door.
• Arginine becomes essential the moment the cycle breaks.

Work through the deck once for recognition, then again a week later to test yourself — each question gives the answer and explains why every other option fails.

More from this system: all genetics and metabolic case decks · pediatric reference values.