Abstract
Rationale: Tuberculin skin test (TST) reaction is still widely used to diagnosis of latent tuberculous infection (LTBI) before the anti TNF-alpha therapy. We aimed to evaluate the effect of anti TNF-alpha therapy on TST reaction.
Method: Eighty-four ankylosing spondylitis patients (22 female, 62 male) before the anti TNF-alpha therapy were evaluated in this prospective study. TST was performed before the anti TNF-alpha therapy and on the 12 month visit. For those patients with a response of <5 mm induration at the initial evaluation, the TST was repeated to detect the booster effect.
Results: Of 84 patients, 18 patients (21.4%) had a negative (0-4 mm) and 66 patients (78.6%) had a positive (≥5 mm) TST response at initial evaluation. The TST responses were converted from negative at initial visit to positive at 1-year repeat in only 4 (4.8%) patients. A significant decrease was observed in the diameters of TST that were repeated on the first year of TNF-a antagonist treatment (6.71±5.6 mm) compared to their initial diameters ((9.15±5.7 mm) (P<0.001).
Conclusion: We concluded that anti TNF-alpha therapy may be associated with suppression on TST reaction.
- © 2011 ERS
