Screening for Latent Tuberculosis Infection in Patients with Autoimmune Diseases Before Initiating TNF-α Inhibitors Therapy

Mater Sociomed. 2018 Mar;30(1):32-37. doi: 10.5455/msm.2018.30.32-37.

Abstract

Introduction: QFT-GIT is more sensitive than TST in patients under immunosuppressive therapy, but TST detects more cases of LTBI. TST remains an inexpensive test worldwide, which does not need laboratory equipment.

Material and methods: Overall, 457 patients having autoimmune diseases were referred. Of those referred, 158 patients were screened with QFT-GIT and TST. No patient in the present study was known to be HIV positive, or had a history of tuberculosis contact the last year. Additionally, neither of the two methods distinguish latent from active TB, and neither one is better at recognizing patients with autoimmune diseases who could avail from preventive chemoprophylaxis.

Results: QFT-GIT is more sensitive than TST in patients under immunosuppressive therapy, but TST detects more cases of LTBI. TST remains an inexpensive test worldwide, which does not need laboratory equipment.

Conclusion: Since the literature for the economic evaluation of LTBI screening has not clearly defined which test is ultimately more cost-effective, low income countries like Greece should continue using TST as the primary method for diagnosis of LTBI.

Keywords: LTBI; TNF; autoimmune disease.