Tuberculin skin test response in patients with juvenile idiopathic arthritis on anti-TNF therapy

Abstract

Background/aim: The aim of this study is to evaluate the effect of biologic drugs on the tuberculin skin test in patients with juvenile idiopathic arthritis.

Materials and methods: A total of 234 biologic drug-using juvenile idiopathic arthritis patients and 45 healthy controls were enrolled in the study. The tuberculin skin test results of the patients, which had been routinely provided during follow-up, were obtained from the patient files. Tuberculin skin test values of ≥5 mm were considered to be positive.

Results: The mean diameter of tuberculin skin test induration was 4.99 ± 6.84 mm (IQR: 0–10 mm) and 7.83 ± 3.47 mm (IQR: 0–16 mm) in patients and controls, respectively (P < 0.05). Tuberculin skin test positivity (≥5 mm) was found in 96 (41%) and 38 (84.4%) of patients and controls, respectively (P < 0.001). There was no induration in 125 (53.4%) patients and 3 (6.6%) healthy controls, respectively (P < 0.001).

Conclusion: In the patients with juvenile idiopathic arthritis who were using biologic drugs, tuberculin skin test induration was significantly lower compared to the control group. Tuberculin skin tests alone seem inadequate for recognition of latent tuberculosis in juvenile idiopathic arthritis patients on anti-TNF therapy.

Keywords: Juvenile idiopathic arthritis; tuberculin test; biologic therapy.