Skip to main content

Table 3 Characteristics of the subjects with inconsistent QFT-GIT results (n = 12)

From: Predictors of persistently positive Mycobacterium-tuberculosis-specific interferon-gamma responses in the serial testing of health care workers

        TST results IFN-γ (IU/ml)  
ID No. Age Sex Country of birth Family history of TB (year) Profession (department/center) -
exposure or risk classification
BCG vaccination Prior TST* Recent TST (mm) Baseline Follow-up IGRA time interval (weeks)
Conversions# (n = 3)         
079 54 F Germany No Room cleaning (B) -
Contact tracing (SNCP, 90 min)§
Yes No 10 0.06 0.46 17
151 39 F Germany 1967 Administration (Pulmonary/G) -
Routine screening (medium risk)
No No 0 0.01 0.46 52
177 50 F Germany 1990 Nursing (ER/G) -
Routine screening (medium risk)
Yes Neg. (45) 10 0.26 4.33 54
Reversions# (n = 6)         
008 30 F Turkey No Room cleaning (B) -
Contact tracing (SNCP, 20 min)§
Unknown No 0 22.66 0.01 17
015 38 M Germany No Nursing (Surgery/B) -
Contact tracing (SNCP, 44 h)§
Yes Neg. (52) 0 0.41 0.00 19
072 54 F Germany 1955 Nursing (Surgery/B) -
Contact tracing (SNCP, 4 h)§
No Neg. (5) 10 0.77 0.16 18
095 39 M Germany No Physical therapy (Rehabilitation/B) - Contact tracing (SNCP, 4 h)§ Yes Neg. (57) 0 29.34 0.00 16
124 44 F Germany No Physical therapy (Rehabilitation/B) - Contact tracing (SNCP, 3 h)§ Yes Neg. (86) 0 0.41 0.00 17
265 26 F Germany No Administration (ER/H) -
Contact tracing (SPCP, 8 h)§
No No 0 0.40 0.00 22
Discordantly indeterminate (n = 3)        
086 50 F Germany No Nursing (Surgery/B) -
Contact tracing (SNCP, 9 h)§
No Pos. (37) 0 0.00 0.00 17
173 20 F Germany No Nursing (Pulmonary/G) -
Routine screening (medium risk)
Yes No 7 0.01 0.01 51
187 26 F Germany No Nursing (Surgery/B) -
Contact tracing (SNCP, 67 h)§
Yes Neg. (60) 0 0.02 0.03 21
  1. *The interval between the prior and the recent TST in months is indicated in parentheses. #QFT-GIT conversions are defined as baseline IFN-γ < 0.35 IU/ml and follow-up IFN-γ ≥ 0.35 IU/ml, QFT-GIT reversions are defined vice versa. §The mean interval between the last exposure to the source case and the baseline evaluation was 17 weeks in individuals initially included in contact investigations. Indeterminate QFT-GIT result due to insufficient IFN-γ mitogen response. B = Bochum; BCG = Bacillus Calmette-Guérin; ER = emergency room; F = female; G = Großhansdorf; H = Hamburg; IFN = interferon; M = male; QFT-GIT = QuantiFERON®-TB Gold In-Tube; SNCP = smear-negative, culture-positive (tuberculosis source case); SPCP = smear-positive, culture-positive (tuberculosis source case); TST = tuberculin skin test.