[needs revising]


Offer testing to close contacts of pulmonary or laryngeal TB treated for less than 2 weeks. Over 2yrs, start with Mantoux. If negative, repeat after 6 weeks with IGRA.

Smear positive get immediate assessment for active TB. Smear negative refer to specialist.

Neonates start isoniazid with pyridoxine. Mantoux at 6 weeks.

Mantoux>= 5mm positive regardless of BCG history.

If positive assess for active TB. If assessment negative, complete treatment for latent (6months). If negative reassess for active TB and consider IGRA test. If IGRA negative stop treatment and give BCG.

For under 2yrs, start isoniazid +/- rifampicin and do Mantoux. Latent treatment with rifampicin is just 3/12.

If Mantoux negative continue treatment, assess for active TB after 6/52 and repeat Mantoux. Consider IGRA as above.

IGRA should only be done alone if Mantoux not available or impractical(?!).

Diagnosing active disease

If clinical signs and suspicion, start treatment pending test results.

Do CXR and 3 cough swabs (including 1 early morning). Young children get induced sputum.

Other testing depends on age and whether suspected pulmonary.

  • If suspected pulmonary, then do rapid diagnostic nucleic acid amplification tests (PCR) – usually only 1 per specimen type (deep cough sputum, induced sputum or gastric lavage) AND IGRA+/or Mantoux
  • For extrapulmonary, after imaging, discuss pros/cons of both biopsy and needle aspiration (NOT into formalin…). Do CXR anyway.
  • if clinical suspicion, HIV Positive, need for rapid result or large contact tracing exercise.
[NICE guidance 2016, updated 2019]