Phenylketonuria – Board-Style Questions

What this deck covers

phenylketonuria 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. Before the label is given
2. What starts this week
3. Never picked up
4. Something must be added
5. Planning a family
6. A week of vomiting
7. Reading the label
8. A trial of tablets
9. Off the diet at sixteen
10. Feeding the newborn
11. Keeping watch at home
12. Why the early years count
13. What the clinic checks
14. The next baby
15. Does it ever stop?
16. An affected mother, an unaffected baby
17. Where it comes from
18. Too far the other way

Diagnoses and management options tested

Across the 18 cases you are asked to choose between options such as: A liver disorder that raises several other amino acids at the same time, A restricted diet with an amino acid drink, started within days, Darkened skin, coarse facial features and a large, protruding tongue, Methionine, which is lost in the urine in this particular condition, Her level must be in range before she conceives, not afterwards, The amino acid drink has raised the level directly, Citric acid, which increases absorption of protein from the gut, A rise in his level, which would then confirm the diagnosis, A reversible effect of the high level, which lifts when control returns, Breastfeeding must stop completely and immediately, A urine test at home each morning using a dipstick, It damages the liver, which recovers once the diet is resumed, Vitamin B12 and bone density, which the restricted diet threatens, Start the restricted diet at once, before any test has been done.

Clinical pearls from this deck

• Exclude a cofactor defect before the diet is started.
• Restrict phenylalanine, replace the other amino acids.
• Untreated: fair, eczematous, musty and severely delayed.
• Tyrosine becomes essential once the pathway is blocked.
• Get the level down before the pregnancy, not after.
• Illness breaks down protein and drives the level up.

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.