Clinical application of an in-house ELISPOT assay in patients with suspicious tuberculous uveitis and no signs of active tuberculosis

The purpose of this study is to evaluate the rate of Mycobacterium tuberculosis infection in uveitis patients using an ELISPOT-IFN-gamma (ELISPOT-MTP) assay and a tuberculin skin test (TST). Fifty-three patients with suspicious tuberculous uveitis, seen at the Ocular Immunology and Uveitis Service, Scientific Institute San Raffaele, Milan, Italy, were compared with 233 healthy control subjects. All uveitis patients, together with healthy control subjects, underwent in-house ELISPOT-MTP assay and then the TST. None of the patients had signs of active tuberculosis. A total of 75.5% of uveitis patients showed positive TST reaction while 58.5% responded positively to ELISPOT-MTP. In healthy individuals, these responses were 30.5% and 25.3%, respectively (p