skip to main content

TB window prophylaxis — RACP Paediatrics MCQ

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

HardIDTB window prophylaxisRACP Paediatrics

A 2-year-old Aboriginal child is a close contact of a smear-positive TB case. The child is well. Mantoux test is 3 mm. Chest X-ray is normal. What is the most appropriate management?

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

Reveal the answer and explanation

Correct answer: A — Isoniazid monotherapy for 6 months

In children <5 years who are close contacts of smear-positive TB, isoniazid window prophylaxis should be started regardless of TST result due to the high risk of rapid progression to active (including disseminated) TB in this age group. The TST should be repeated at 8-12 weeks. If still negative, prophylaxis can be stopped (unless immunocompromised).

Reference: Australian Therapeutic Guidelines – 2024 – Antibiotic; RCH Melbourne – 2023 – TB CPG