Giardiasis — MCCQE Part 1 MCQ

Correct answer: A — Giardiasis

Giardiasis is the single best answer because the age, timing, examination findings and investigations in the vignette fit Giardiasis 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 Canadian public health enteric disease guidance, with attention to acuity, safety-netting and local provincial pathways.

Reference: Canadian public health enteric disease guidance