Diagnostics for active TB

(CID 2017;64:11)

• Pulmonary TB:

  • common CXR findings discussed above;
  • induced sputum AFB smear & culture (3 samples at ↣ least 8 h apart)
  • ± NAAT/ PCR (GeneXpert);
  • consider bronchoscopy + BAL ± transbronchial biopsy.
  • GeneXpert can also detect RIF resistance (non-bloody sputum only).
  • Sp 98%/Se 74%,
  • independent of HIV status.

• BUG: Interferon-gamma release assay 沒辦法區分 active 和 latent TB