TABLE 8

Characteristics of FDA-cleared and FDA-market-authorized NAATs for M. tuberculosis complex detection according to the manufacturers' package insertsb

TestSpecimen typesMethodologySensitivities (%)Specificity (%)Tests for inhibitors
AFB smear negativeAFB smear positiveAFB smear negativeAFB smear positive
Hologic Amplified MTDAFB smear-positive and -negative concentrated sediments prepared from sputum, bronchial specimens, or tracheal aspiratesTranscription-mediated amplification of rRNA and detection by hybridization protection assay64.0 for single specimen, 71.4 for 2 specimens87.5 for single specimen, 100 for 2 specimens99.1–100100Noa
Cepheid Xpert MTB/RIFAFB smear-positive and smear-negative sputum samples or concentrated sediments prepared from sputumReal-time PCR using molecular beacon probes to the 81-bp rifampin resistance-determining region of rpoB73.1 for single specimen, 90.0 for 3 specimens97.8 for single specimen, 99.5 for 3 specimens97.9–99.097.9–99.0Yes
  • a Can be assessed with additional steps.

  • b See references 147 and 148. AFB, acid-fast bacilli.