The Use of a Novel ESAT6/CFP10 Skin Test in Diagnosis of Latent Tuberculosis Infection Among Rheumatologic Patients

What this Trial Is About

Researchers are evaluating a new skin test called ESAT6/CFP10 (C-TST) to detect latent tuberculosis infection (LTBI) in patients with rheumatologic diseases before they start treatment with biologic and targeted synthetic disease-modifying antirheumatic drugs (b/tsDMARD). This prospective observational study aims to assess the performance of the C-TST and analyze its impact on clinical outcomes and healthcare costs compared to existing testing methods. Participants will receive two skin tests on the same day using the Mantoux technique: the standard tuberculin skin test (TST) with purified protein derivative (PPD) RT23 on one forearm and the new C-TST on the other forearm. Blood samples for the Interferon-Gamma Release Assay (IGRA) will also be collected. Skin test results will be read within 48 to 72 hours. If LTBI is detected, treatment will follow current clinical guidelines, with regular monitoring continuing for two years. Throughout the study, participants will be monitored through clinical visits and tests to measure the agreement between different LTBI tests, the sensitivity and specificity of the C-TST, and the proportion of new tuberculosis cases prevented. The main outcomes include skin test readings at 48-72 hours and at two weeks, plus follow-up for TB disease occurrence over two years. This approach aims to provide evidence on the diagnostic accuracy of the C-TST and its usefulness in guiding treatment decisions for rheumatologic patients.

ESAT6/CFP10 Skin Testing for TB Infection in Rheumatologic Patients