PURPOSE: To use Quanti-feron TB ®-Gold (QFT-G) as an aid to diagnose tuberculosis (TB) infection in a health center setting among foreign-born persons.
METHODS: Between December 9, 2006 and April 24, 2007 (the time this abstract was prepared for submission) QFT-G was introduced and has been used as an aid to diagnose TB infection in foreign-born, non-pregnant, immunocompetent adults seen at eight (8) Suffolk County, New York, operated health centers.
RESULTS: 423 persons were tested during this time period. All of these persons had a QFT-G assay performed, none had a tuberculin skin test (TST) placed. There were 53 QFT-G positive (12.5%); 355 QFT-G negative (84%) and 15 indeterminant QFT-G results (3.5%) obtained. This number compared to a TST positive rate of 36% (426/1193) that we previously reported in a targeted tuberculosis testing and treatment program amongst foreign-born persons in Suffolk County between 2000-2005.
CONCLUSION: The QFT-G assay produced a lower positive rate (12.5%), as compared to the TST (36%), in this foreign-born population resulting in fewer diagnoses of latent TB infection (LTBI). If positive reactors are placed on the prefered Centers for Disease Control and Prevention (CDC) 9-month course of isoniazid to treat LTBI, for every 100 patients tested with QFT-G, when compared with the TST, one should expect approximately 24 fewer positive reactors. Assuming each positive reactor requires one (1) patient encounter for initiation of treatment (including medical, laboratory and radiographic evaluation) and nine (9) patient encounters to complete the preferred CDC 9-month course of isoniazid to treat LTBI (total 10 visits), for every 100 foreign-born persons tested for TB infection with QFT-G (as compard with the TST), about 240 patient encounters should be eliminated. This should generate considerable cost savings in this population.
CLINICAL IMPLICATIONS: In a foreign-born population using QFT-G as an aid to diagnose TB infection should result in considerable cost saving due to its lower positivity rate (12.5%) when compared to the TST (36%).
DISCLOSURE: Lewis Mooney, No Financial Disclosure Information; No Product/Research Disclosure Information