ESAT6/CFP10 Skin Testing for TB Infection in Rheumatologic Patients

The aim of the study is to pilot the application of a novel ESAT6/CFP10 (C-TST) skin test in rheumatologic disease patients prior to initiation of treatment with biologic and/or targeted synthetic disease-modifying antirheumatic drugs (b/tsDMARD). This is a prospective observational study involving the recruitment of patients with rheumatologic diseases who are planned for initiation of b/tsDMARD. Eligible patients would undergo skin testing by the Mantoux technique with purified protein derivative (PPD) RT23 on one forearm and C-TST on the other, alongside routine blood sampling for Interferon-Gamma Release Assay. The skin test results would be read within 48-72 hours afterwards. Treatment of TB infection would be provided in accordance with current clinical guidelines, followed by regular clinical monitoring for 2 years. Analyses involve performance evaluation of C-TST, and decision-analytical modelling incorporating multiple Markov process to evaluate the impact of management by LTBI testing methods on clinical outcomes and health care costs.