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A pillar of the WHO End TB Strategy is targeted latent tuberculosis infection (LTBI) testing to identify persons who would benefit from TB preventive treatment (TPT).1 The WHO recommends the interferon-gamma release assays (IGRAs), tuberculin skin test (TST) or Mycobacterium tuberculosis antigen-based skin tests without preference, for LTBI detection in persons at high risk for recent TB infection or of progression to active disease,2 whereas guidelines from low TB incidence/high income countries preferentially recommend the IGRAs over the TST especially in those who have received BCG vaccination or who are not likely to return for TST reading.3 Both TST and IGRAs have shown similar (although disappointingly low) positive predictive values for progression to TB disease in meta-analyses which included subjects from a variety of settings and population subgroups (eg, contacts, healthcare workers, immunosuppressed persons and migrants).4 5 The IGRAs have several advantages over the TST, namely its superior specificity in BCG-vaccinated persons, a machine readout which is not subject to intra or inter-reader variability, and no requirement for a return visit for the test result. The TST has the advantage of low cost and simplicity, and a large body of evidence supporting its utility in LTBI detection for TPT. To optimise its performance, different cut-offs are used according to epidemiological and clinical risk factors in its interpretation. The addition of IGRA to TST has been used to rule out false-positive TST results in BCG-vaccinated persons or to improve test sensitivity, for example, in immunocompromised persons who may test falsely TST-negative. Using a Bayesian Latent Class Analysis model, Zavala et al found the sensitivity/specificity of dual testing with TST-QuantiFERON-TB Gold-in-Tube (QFT) in non-US-born, HIV negative persons to be 73.1%/99.4%, which was not superior to that of QFT alone, which was 77.7%/98.3%.6