Vitamin B12 deficiency neuropathy — MCCQE Part 1 MCQ

Correct answer: D — Start vitamin B12 replacement and evaluate the cause

Start vitamin B12 replacement and evaluate the cause is the single best answer because the age, timing, examination findings and investigations in the vignette fit Vitamin B12 deficiency neuropathy 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 nutrition and haematology guidance, with attention to acuity, safety-netting and local provincial pathways.

Reference: Canadian nutrition and haematology guidance