Comparison of the Quantiferon®-TB GOLD (in Tube) Assay With Tuberculin Skin Testing for Detecting Latent Tuberculosis Infection in Patients With Chronic Liver Disease Being Evaluated for or Awaiting Liver Transplantation

Tuberculosis (TB) is an important cause of morbidity and mortality in organ transplant recipients. Management of tuberculosis in this setting is challenging due to the complexity of diagnosis and the potential toxicity of anti-TB therapy, especially in liver transplant candidates and recipients. Although the tuberculin skin test (TST) is recommended for screening of latent tuberculosis infection (LTBI) in all candidates for liver transplantation, the performance of the TST in this setting is less than optimal, due to a lack of specificity (false-positive results due to interaction with BCG vaccine and other mycobacterial infections), and a lack of sensitivity in a population that is relatively immunocompromised. Recently, a new test named QuantiFERON-TB Gold (QFT-G) has been approved for the diagnosis of LTBI. QFT-G detects the release of interferon-gamma (IFN-γ) by sensitized white cells after incubation of whole blood with TB antigens. QFT-G is expected to be more specific than TST. However, there are no studies defining the performance of QFT-G in a population of patients on a waiting list for liver transplantation. We plan to estimate the usefulness of the QFT-G test for the diagnosis of LTBI in a cohort of patients with end-stage liver disease. We hypothesize that the QFT-G test will correlate better with the risk of LTBI. This study advances research on the prevention of a serious bacterial infection that can have devastating consequences in the post-transplant setting. The new diagnostic strategy may more accurately determine the presence of LTBI, thereby allowing appropriate therapy.