skip to main content

Microcytic anemia — ABIM Board MCQ

Instant feedback + full explanation. One question, done properly.

HardHematology/OncologyMicrocytic anemiaABIM Board

A 72-year-old with CKD takes colchicine and clarithromycin, then develops vomiting and diarrhea followed by shock, ventricular dysrhythmia, leukopenia, thrombocytopenia, and rising lactate. The last dose was 18 hours ago. Which management strategy is most appropriate?

Educational content. Not a substitute for clinical judgement or local policy.

Reveal the answer and explanation

Correct answer: A — Stop both medicines and provide immediate toxicology-led multiorgan support

The best answer is “Stop both medicines and provide immediate toxicology-led multiorgan support”. This is severe colchicine toxicity amplified by renal impairment and CYP3A4/P-glycoprotein inhibition from clarithromycin. After the early gastrointestinal phase, distributive or cardiogenic shock, dysrhythmia, marrow failure, and multiorgan injury may emerge. There is no routinely available specific antidote, and colchicine has a large volume of distribution that limits dialysis removal. Immediate critical care, toxicology consultation, serial blood counts, and aggressive organ support are required.

Reference: Colchicine poisoning: the dark side of an ancient drug: https://pmc.ncbi.nlm.nih.gov/articles/PMC4656054/