Identification of individuals with a tuberculosis infection is a very important element for the control of tuberculosis. The currently used tuberculin skin test has poor sensitivity and specificity. Recently, an important advance in tuberculosis diagnosis occurred with the development of in vitro T cell-based IFN-gamma release assays. The aim of this study was to compare a RD1-based in-house ELISPOT-IFN-gamma assay with a commercial (T-SPOT.TB) assay for the diagnosis of tuberculosis infection. The results showed an almost complete concordance between the two assays, confirming that our restricted but highly selected pool of peptides is sufficient to detect tuberculosis infection.