ESAT6/CFP10 (C-TST) skin test to detect TB infection in rheumatology patients

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

Observational Chinese University of Hong Kong · NCT06796647

This study will try a new ESAT6/CFP10 skin test (C-TST) alongside standard PPD and blood IGRA tests to see if it detects latent TB in adults with rheumatologic diseases before they start biologic or targeted synthetic DMARDs.

Quick facts

Study typeObservational
Enrollment100 (estimated)
Ages18 Years to 65 Years
SexAll
SponsorChinese University of Hong Kong Academic / other
Locations2 sites (Hong Kong, Hong Kong and 1 other locations)
Trial IDNCT06796647 on ClinicalTrials.gov

What this trial studies

This prospective observational study in Hong Kong will recruit adults with rheumatologic diseases who are scheduled to start b/tsDMARD therapy. Participants will receive intradermal PPD RT23 on one forearm and ESAT6/CFP10 (C-TST) on the other, plus a QuantiFERON-TB Gold IGRA blood test, with skin readings at 48–72 hours. LTBI treatment will follow current clinical guidelines where indicated and participants will be clinically followed for two years. Analyses include concordance (kappa), sensitivity and specificity of C-TST versus PPD and IGRA, and decision-analytic Markov modelling to estimate clinical and economic impacts of different LTBI management strategies.

Who should consider this trial

Good fit: Adults aged 18–65 with a diagnosed rheumatologic disease who can communicate in Chinese or English and are planned to start b/tsDMARD therapy are eligible.

Not a fit: Patients with active TB, those already receiving TB or LTBI treatment, individuals with significant mental illness, or prisoners are excluded and would not benefit from participation.

Why it matters

Potential benefit: If successful, the C-TST could offer a more specific and practical way to identify latent TB before immunosuppressive therapy, potentially reducing missed infections and unnecessary preventive treatment.

How similar studies have performed: Similar ESAT6/CFP10-based skin tests have shown promising concordance with IGRA in general populations, but evidence is limited in rheumatologic or immunosuppressed patient groups.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. adult of age ≥ 18 and up to 65 years;
2. diagnosis of at least one classified rheumatologic disease; and
3. being planned to receive b/tsDMARDs therapy,
4. can communicate in Chinese and/or English.

Exclusion Criteria:

* diagnosis of active TB diseases,
* currently receiving TB or LTBI treatment;
* concurrent mental illnesses;
* prisoners.

Where this trial is running

Hong Kong, Hong Kong and 1 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Tuberculosistuberculosisskin testingESAT6/CFP10rheumatology patients
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.