Positive Conversion of Tuberculin Skin Test and Performance of Interferon Release Assay to Detect Hidden Tuberculosis Infection During Anti-Tumor Necrosis Factor Agent Trial

Article Figures & Data

Table 1.

Patients characteristics and tuberculin skin test (TST) conversion rate.

Characteristics	All Participants (%), n = 86	TST Conversion No. (%)	Multivariate OR (95% CI)
Age, yrs, mean (SD)	39.3 (15.8)
≤ 29	29 (33.7)	7 (24)	1.00
30–39	17 (19.8)	10 (58.8)^*	3.93 (0.82–18.86)
40–49	14 (16.3)	7 (50)	4.39 (0.68–28.27)
≥ 50	26 (30.2)	4 (15.4)	0.78 (0.09–6.71)
Women, no. (%)	48 (55.8)	10 (20.8)	0.35 (0.08–1.62)
Diagnosis
RA	40 (46.5)	7 (17.5)	1.00
AS	34 (39.5)	17 (50)	1.01 (0.12–8.75)
JRA	9 (10.5)	1 (11.1)	0.44 (0.02–9.67)
Other	3 (3.5)	3 (100)	—
Tuberculin skin tested in the past	23 (26.7)	7 (30.4)
BCG vaccination	77 (89.5)	23 (29.9)	0.34 (0.08–1.39)
Duration of TNF inhibitor therapy
1–2 yrs	35 (40.7)	7 (20)	1.00
2–3 yrs	26 (30.2)	10 (38.5)	2.78 (0.68–11.38)
≥ 3 yrs	25 (29.1)	11 (44)^*	3.44 (0.83–14.22)
TNF antagonists
Etanercept	66 (76.7)	20 (30.3)	1.00
Infliximab	20 (23.3)	8 (40)	1.53 (0.54–4.33)
DMARD, no. (%)	49 (57)	13 (26.5)	0.53 (0.21–1.32)
Corticosteroids, no. (%)	35 (40.7)	5 (14.3)	0.35 (0.08–1.62)

RA: rheumatoid arthritis; AS: ankylosing spondylitis; JRA: juvenile rheumatoid arthritis; BCG: bacillus Calmette-Guérin; TNF: tumor necrosis factor; DMARD: disease modifying antirheumatic drugs; OR: odds ratio; CI: confidence interval,
↵* p < 0.10.

Table 2.

Comparison of characteristics of RA and AS patients.

RA: rheumatoid arthritis; AS: ankylosing spondylitis; SD: standard deviation; MTX: methotrexate; TNF: tumor necrosis factor; BCG: bacillus Calmette-Guérin;
↵* p < 0.05,
↵** p < 0.01.