Table 1– Tuberculin skin test (TST), interferon (IFN)-γ and IFN-γ-induced protein (IP)-10 results in children by sputum grade of the index case
Bacilli count of the adultControlsTotal
++++++Scanty
Subjects1510918818156486
TST
 Positive13 (86.7)46 (43)95 (54.6)14 (82.4)20 (12.8)469
 Intermediate019 (17.8)28 (16.1)1 (5.9)15 (9.6)
 Negative2 (13.3)42 (39.3)51 (29.3)2 (11.8)121 (77.6)
IFN-γ
 Positive8 (57.1)53 (50.5)74 (43.8)3 (17.6)20 (13.1)458
 Indeterminate5 (35.7)13 (12.4)24 (14.2)10 (58.8)25 (16.3)
 Negative1 (7.1)39 (37.1)71 (42)4 (23.5)108 (70.6)
IP-10#
 Positive7 (50)60 (59.4)96 (55.8)4 (23.5)9 (5.8)458
 Negative7 (50)41 (40.6)76 (44.2)13 (76.5)145 (94.2)
  • Data are presented as n or n (%). #: IP-10 positive grading ≥3,022 pg·mL−1, as calculated by the receiver operating characteristic curve.