Chapter 28 — Exercises

Three tiers. 🔄 retrieval; 🪞 reflection.

Tier 1 — Recall and Comprehension

R1. Give §28.1's eight mechanisms with speed and dose-dependence. ⚠️ Which two are the ones where small amounts matter?

R2. ⚠️ What is nocebo in this context, and why is "it's nocebo" not the same as "you're making it up"?

R3. Name the common allergens. ⚠️ Which are usually outgrown and which usually persist?

R4. ⚠️ State the first-line treatment for anaphylaxis, the route, and the site. What do antihistamines do and not do?

R5. ⚠️ Give §28.3's recognition table by system. What is the rule that removes hesitation?

R6. ⚠️ Why is "waiting for hives" dangerous?

R7. Name five risk factors for fatal anaphylaxis. ⚠️ Which is most important?

R8. ⚠️ Name five cofactors that can convert a tolerated exposure into anaphylaxis.

R9. ⚠️ How does anaphylaxis present differently in an infant, and why?

R10. ⚠️ What do skin prick tests and specific IgE measure? What is the gold standard? State the rule about history and testing.

R11. ⚠️ Why is testing a broad panel in someone with no suggestive history harmful?

R12. What is coeliac disease? ⚠️ Name six non-gastrointestinal presentations.

R13. ⚠️ Why must coeliac testing happen before removing gluten? What are the four consequences of getting this wrong?

R14. ⚠️ Give six practical difficulties of the gluten-free diet from §28.6's subsection. What's the most common post-diagnosis error?

R15. ⚠️ What proportion of the world's adults are lactase non-persistent? Why is calling it a disease a framing error?

R16. ⚠️ What did the fructan-versus-gluten crossover study find? State §28.8's honest position in both halves.

R17. ⚠️ What do IgG food panels actually measure? Name four other invalid tests and four harms.

R18. Explain oral allergy syndrome. ⚠️ Why is the cooked form usually tolerated?

R19. ⚠️ Distinguish desensitization from tolerance. What does OIT not change?

R20. ⚠️ Give §28.14b's six hypotheses for rising allergy prevalence. Which row does the chapter call uncomfortable, and why?

Tier 2 — Application

A1. 🔄 Assign the mechanism. For each, name the mechanism from §28.1 and say whether dose matters:

a) Lip tingling after a raw apple, fine with apple pie b) Hives and wheeze within ten minutes of a cashew c) Bloating and wind three hours after a large latte d) Chronic fatigue and iron-deficiency anaemia, no GI symptoms e) Headache and flushing after aged cheese and red wine f) Symptoms after onion and garlic, worse with a large portion g) Vomiting two hours after a food, in an infant, with pallor and floppiness

A2. ⚠️ The anaphylaxis decision. For each, would you give adrenaline?

a) Hives only, no other symptoms, after a known allergen b) Vomiting plus a hoarse voice c) Sudden faintness and pallor after a meal, no rash d) Itchy mouth after a raw peach, no other symptoms e) Wheeze after a known allergen, in someone with asthma

⚠️ For any "no," state exactly what would change your answer.

A3. The gluten pathway. Someone says they feel better without gluten and wants to know if they're coeliac.

a) ⚠️ What must you establish first? b) They've already been gluten-free for four months. What now? c) ⚠️ They refuse the gluten challenge. What are the four consequences? (§28.6) d) What would you actually do?

A4. ⚠️ The IgG panel conversation. Someone shows you a result with 23 reactive foods.

a) What did the test measure? b) ⚠️ They eliminated everything and felt better. Explain that without dismissing it. c) What do you do next, practically? d) ⚠️ What are you screening for before you say anything reassuring?

A5. The dairy threshold. Someone has excluded all dairy for six years after post-gastroenteritis symptoms.

a) ⚠️ What's likely to have happened? b) How would you test the threshold? c) ⚠️ What nutritional issue have they accumulated, and why does it matter more at some ages?

A6. Design the school plan for a nine-year-old with peanut anaphylaxis.

⚠️ Cover: devices, who is trained, food at school, birthdays and parties, trips, and what the child themselves needs to know.

Tier 3 — Analysis and Synthesis

S1. ⚠️ The language problem. §28.9b argues vocabulary allocates seriousness.

a) Trace the mechanism precisely: how does over-use of "allergy" endanger person 1? b) ⚠️ Would a mandated vocabulary help? Design it, then say what breaks. c) The MSG syndrome was named after a cuisine. ⚠️ Find two other examples where a name did persuasive work the evidence didn't.

S2. Sensitization versus allergy. §28.4's distinction.

a) ⚠️ Explain, using base rates, why broad-panel testing generates mostly false positives. b) Why is component-resolved testing better? c) ⚠️ Design the guidance you'd give a GP about when to test at all.

S3. ⚠️ Non-coeliac gluten sensitivity. §28.8 holds both halves.

a) Steelman the position that a distinct gluten-mediated entity exists. b) ⚠️ Design the study that would identify the residual group. Why is it hard? c) ⚠️ How should a clinician talk to someone whose symptoms are real and whose attribution is probably wrong? Write it, using Chapter 17 §17.13's rules.

S4. The restriction pattern, four instances. Cancer (Ch 26), CKD (Ch 26), IBS (Ch 27), and here.

a) ⚠️ What does §28.11 say makes this instance different? b) Why does a test make a restriction more durable than a hunch? c) ⚠️ Design the intervention that would break the cycle at each of the four sites.

S5. ⚠️ Stale guidance that caused harm. §28.14b's fifth row.

a) Was the delayed-introduction advice reasonable when issued? ⚠️ Justify carefully. b) What should have triggered an earlier reassessment? c) ⚠️ What current recommendation in this book do you think is most likely to look like this in twenty years? Argue it.

S6. 🔄 The immunotherapy decision. §28.13's table.

a) ⚠️ Write the consultation — under 200 words — that gives a family what they need to decide. b) What is the single most important sentence in it? c) ⚠️ The chapter says a family that declines is not being negligent. Do you agree? What would change your view?

🪞 Reflection

M1. ⚠️ Do you say "allergy" about something that isn't one? Would you change it after this chapter?

M2. ⚠️ Have you eliminated a food without ever testing a smaller amount? Which, and how long ago?

M3. §28.11 says the elimination often helps at first because it removes a bundle. ⚠️ Have you ever credited a specific removal for a general improvement? (Chapters 3, 17 and 19 all asked a version of this. Has your answer changed?)

M4. ⚠️ If you know someone with a genuine allergy — do you know where their devices are, and would you use one? Would you hesitate? §28.3 exists because of that hesitation.

M5. 🔄 ⚠️ §28.14b says advice that was reasonable when issued probably caused harm while it stood. How should that affect how you hold current advice — including this book's?