Hypertrophic pyloric stenosis — MCCQE Part 1 MCQ

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ModerateNausea/VomitingHypertrophic pyloric stenosisMCCQE Part 1

A 5-week-old boy has progressively worsening projectile non-bilious vomiting after feeds, remains hungry and has a palpable epigastric olive. Which of the following is the most appropriate next step?

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Correct answer: E — Correct dehydration and electrolytes before pyloromyotomy

Correct dehydration and electrolytes before pyloromyotomy is the single best answer because the age, timing, examination findings and investigations in the vignette fit Hypertrophic pyloric stenosis better than the alternatives. The most tempting distractor is less appropriate because it either treats a neighbouring presentation, delays a time-critical intervention, or ignores a key discriminator in the stem. The remaining options are suboptimal because they would miss the diagnosis, use an investigation or treatment in the wrong sequence, or fail to address safety and follow-up. Canadian practice should be anchored to CPS paediatric surgery guidance, with attention to acuity, safety-netting and local provincial pathways.

Reference: CPS paediatric surgery guidance