Table 3

TST+ subjects with a past MTB exposure: trends of RD1 test during follow up in the responders*

Group of subjects analysed
Number of subjects
N (%)
Time 1
0 months
Time 2
1–2 months
Time 3
6 months
Time 2 vs. time 1
Time 3 vs. time 1



IFN-gamma (IU/ml)



No INH
5 (100)





PHA
5 (100)
14.2 ± 3.4
17.1 ± 4.5
17.5 ± 4.6
Ns
Ns
PPD
5 (100)
31.4 ± 2.5
33 ± 3.4
29.3 ± 4.5
Ns
Ns
QTF-G
5 (100)
16.4 ± 5.1
12.3 ± 4.4
16.3 ± 6.7
Ns
Ns
RD1 proteins
5 (100)
11.8 ± 3.8
8.9 ± 3.2
13.5 ± 6.1
Ns
Ns
RD1 peptides
5 (100)
6.1 ± 2
2.2 ± 0.5
4.6 ± 2
Ns
Ns







INH therapy
9 (100)





PHA
9 (100)
17.7 ± 6
20.4 ± 4.4
17.8 ± 4.1
Ns
Ns
PPD
9 (100)
19.6 ± 4.5
19.4 ± 4.7
24.2 ± 5.2
Ns
Ns
QTF-G
9 (100)
15.2 ± 4
11.3 ± 4
9.4 ± 2.7
Ns
Ns
RD1 proteins
9 (100)
6 ± 2
8.8 ± 3.3
11.9 ± 5.2
Ns
Ns
RD1 peptides
6 (66)
4.4 ± 2.7
4.1 ± 1.4
7 ± 3
Ns
Ns

*Responders are defined as those responding to the tests at baseline.

T1: time 1 (baseline); T2. time 2 (after 1–2 months INH therapy), T3: time 3 (after 6 months, at therapy completion). IFN: interferon; PHA: Phytohemagglutinin; PPD: purified protein derivative; RD: region of difference; QTF-G: QuantiFERON TB Gold; IFN: interferon; IU: international units. INH: isoniazid; ns: not statistically significant.

Goletti et al. Respiratory Research 2007 8:5   doi:10.1186/1465-9921-8-5