| Popis: |
A rural town in South Africa.To compare the performance of Quanti-FERON assays with the tuberculin skin test (TST) for identifying latent tuberculosis infection (LTBI) in a high TB burden community.In a cross-sectional study in healthy adults, we applied the TST and took blood for the three generations of QuantiFERON assays.Of 358 participants whose results were analysed, 291 (81%) had a TST result ofor = 10 mm induration, and 187 (52%)or = 15 mm. QuantiFERON-TB was positive in 215 (60%), QuantiFERON-TB Gold in 137 (38%), and QuantiFERON-TB Gold (In-Tube method) in 201 (56%). There was poor agreement between TST and QuantiFERON tests, and between the different generations of QuantiFERON tests (kappa = 0.12-0.50). Of the subset with TST indurationsor = 15 mm, 30-56% had negative QuantiFERON tests. However, positive Quanti-FERON tests were associated with males, who have a higher incidence of TB in this area.We showed poor agreement between TST and the different QuantiFERON tests in diagnosing LTBI. The surprising discordance between the Quanti-FERON TB Gold and QuantiFERON TB Gold (In-Tube method) tests needs to be investigated further. |
