Comparison of Quantiferon-TB Gold versus Tuberculin Skin
Test for Tuberculosis Screening in Inflammatory Bowel Disease
Full Article (PDF file)
Gianluca Andrisani, Alessandro Armuzzi, Alfredo Papa, Manuela Marzo, Carla Felice, Daniela Pugliese, Italo De Vitis,
Gian Lodovico Rapaccini, Luisa Guidi
Catholic University, Rome,
Background & Aim: Screening for latent tuberculosis (LTB) is recommended before starting anti-TNF-α
therapy. We compared the performance of Quantiferon-TB Gold (QFT-G) with the tuberculin skin test (TST)
for the screening of LTB in a population of inflammatory bowel disease (IBD) patients who were candidates
for anti-TNF-α therapy.
Methods: Ninety-two IBD patients who were candidates for anti-TNF-α therapy were tested with QTF-G
and TST. Concomitant therapy and laboratory parameters were recorded.
Results: One subject was vaccinated with Bacille Calmette Guerin (BCG), 76% of patients were on
immunosuppressive therapy (IST), and all patients had a negative TB history and negative chest X-ray.
Agreement between the two tests was observed in 89.2% of patients (79.4% +/+, 9.8% -/-), QFT-G+/TSTwas
observed in 4.4% (4) patients, and QFT-G-/TST+ was observed in 5.5%, one of which was previously
vaccinated. All disagreements were observed in patients on IST (14.3% in this group). The agreement analysis
showed moderate strength among the patients (k=0.508), while the agreement was only fair in the subgroup
of patients on IST (k=0.388).
Conclusion: Given the high risk of LTB reactivation in patients subjected to anti-TNF-α therapy, our results
suggest that in our population, with low TB rate and very low BCG vaccination rate, both tests could be
Key words: inflammatory bowel disease - latent tuberculosis - Quantiferon test - tuberculin skin test - anti-
Abbrevations: INHA: isoniazide; AZA: azathioprine; BCG: Bacille Calmette Guerin; CFP-10: culture filtrate
protein-10; ESAT-6: early secretory antigen target-6; IBD: inflammatory bowel disease; IFN: interferon;
IGRA: interferon-gamma release assay; IST: immunosuppressive therapy; LTB: latent tuberculosis; QFT-G:
Quantiferon-TB gold; TB: tuberculosis; TNF-α: tumor necrosis factor-alpha; TST: tuberculin skin test.