TABLE 3.

Test results for clinical strains of MDR M. tuberculosis (n = 133) for susceptibility to second-line drugs

Antibiotic (concn [μg/ml])MGIT 960 resultaRRM/MPAa,b resultsRate of agreement (%)Sensitivityc (%)Specificityd (%)PPVe (%)NPVf (%)
SR
AMI (1.0)S10819996999699
R23
CAP (1.25)S10529792989298
R224
OFL (1.0)bS97100100100100100
R34
RIFB (0.5)S62999810010075
R125
PRO (2.5)S11939675988298
R29
PRO (5.0)S12439763998398
R5
  • a S, susceptible; R, resistant.

  • b Values are numbers of isolates. A total of 132 M. tuberculosis clinical isolates were tested.

  • c The sensitivity, i.e., the ability of MGIT 960 to detect true resistance compared with the RRM results.

  • d The specificity, i.e., the ability of MGIT 960 to detect true susceptibility compared with the RRM results.

  • e PPV, positive predictive value.

  • f NPV, negative predictive value.