European Society of Mycobacteriology - Instituto Nacional de Saúde ...

CLINICAL PERFORMANCE OF QUANTIFERON-TB GOLD ASSAY (QFT) FOR THE
DIAGNOSIS OF LATENT TUBERCULOSIS IN DIFFERENT PATIENT GROUPS
PP-71
Karabela Simona, Papaventsis Dimitrios, Nikolaou Stavroula, Konstantinidou Efthimia, Sainti Asimina, Ioannidis Panayotis,
Kanavaki Sofia
National Reference Center for Mycobacteria, “Sotiria” Hospital, Athens, Greece
Objective
The purpose of this study was to evaluate the performance and usefulness of Quantiferon-TB Gold In-Tube (QFT,
Cellestis, Australia) in the diagnosis of latent tuberculosis and to compare it with the tuberculin skin test (TST).
Methods
A cohort of 395 high risk adults was prospectively evaluated. Study groups consisted of 139 neoplastic patients, 98 with
autoimmune diseases (SLE, rheumatoid and psoriatic arthritis), 20 immunossupressed (e.g. HIV, hemodialysis) and 26
Intensive Care Unit (ICU) patients, and 112 patients with no underlying disease. The TST was performed according to the
Mantoux method and the QFT assay according to the manufacturer’s instructions. The cut-off value for a positive result
was ≥0.35 IU/ml interferon-gamma (IFN-γ). QFT and TST were simultaneously performed in 297 patients.
Results
Overall, QFT gave a positive result in 72/395 (18.22%) patients. Among the different risk groups, ICU and immunosuppressed
patients represented the highest positive rates (19% and 20%, respectively). Indeterminate results (7% on
the whole) were more often seen in ICU (34.6%), neoplastic (7.2%) and in patients with autoimmune disease (7.2%).
Indeterminate results represented