Table 2. Characteristics of patients with discordant results on the TST and QFT assays.

	TST+/QFT− (n = 60)	TST−/QFT+ (n = 41)	P value
Age, years	33.0 (27.0–42.8)	53.0 (40.5–60.0)	< 0.001
Sex, male	48 (80.0)	21 (51.2)	0.002
History of TB treatment	5 (8.3)	3 (7.3)	>0.999
BCG scar	49 (81.7)	24 (58.5)	0.011
Underlying disease			< 0.001
Rheumatoid arthritis	10 (16.7)	24 (58.5)
Ankylosing spondylitis	50 (83.3)	17 (41.5)
Immunosuppressive drugs	18 (30.0)	28 (68.3)	<0.001

The data are presented as median and interquartile range or as number (%).

TST = tuberculin skin test; QFT = QuantiFERON-TB Gold In-Tube; TB = tuberculosis; BCG = Bacillus Calmette-Guérin.