1 Division of Pulmonary and Critical Care Medicine, University of Arkansas for Medical Sciences, and Central Arkansas Veterans Healthcare System (CAVHS).
Ann Am Thorac Soc. 2014 Mar;11(3):296-302. doi: 10.1513/AnnalsATS.201310-378OC.
IFN-γ release assays (IGRAs) including the QuantiFERON-TB gold in-tube test (QFT-GIT) are increasingly used in place of the tuberculin skin test (TST) in surveillance programs for Mycobacterium tuberculosis infection in the United States. However, data on conversions, reversions, and predictive value of QFT in such programs for health care workers (HCWs) are limited.
The purpose of this study is to assess long-term reproducibility and conversion and reversion rates of QFT-GIT among HCWs who underwent serial testing at a tertiary care center in the United States.
Retrospective chart review of HCWs at the Central Arkansas Veterans Healthcare System (CAVHS) who underwent serial testing with QFT-GIT as a part of their employee screening between November 1, 2008 and January 31, 2011.
A total of 2,303 HCWs had at least 2 QFT-GITs 1 year apart. The initial QFT-GIT was positive for 69 and 2 were indeterminate. Of these 69 HCWs, 31 (45%) reverted on repeat testing, and 25 of 31 (80.6%) HCWs who reverted had a negative look-back TST. Of the 2,232 HCWs with an initial negative QFT-GIT, 71 (3.2%) converted on repeat testing. A third QFT-GIT assay was performed in 41 of the 71 converters and 90% (37 of 41) reverted back to negative. Only two HCWs had TST and QFT-GIT conversion.
Poor IGRA reproducibility and a low predictive value of QFT-GIT conversions indicate that QFT-GIT with current interpretation criteria should not be used for serial screening of U.S. HCWs. Negative TSTs have higher reproducibility than QFT-GIT for serial testing of HCWs in low tuberculosis incidence settings.
干扰素-γ 释放检测（IGRAs），包括 QuantiFERON-TB gold in-tube 检测（QFT-GIT），在美国结核分枝杆菌感染监测项目中越来越多地替代结核菌素皮肤试验（TST）。然而，在美国，关于 QFT 在这些医务人员（HCWs）监测项目中的转化、逆转以及预测价值的数据有限。
本研究旨在评估在美国一家三级保健中心接受连续 QFT-GIT 检测的 HCWs 的长期可重复性以及 QFT-GIT 的转化和逆转率。
对 2008 年 11 月 1 日至 2011 年 1 月 31 日期间，作为员工筛查的一部分，在阿肯色州中部退伍军人医疗保健系统（CAVHS）接受连续 QFT-GIT 检测的 HCWs 进行回顾性病历审查。
共有 2303 名 HCWs 至少有 2 次 QFT-GIT 间隔 1 年。最初的 QFT-GIT 阳性率为 69 例，2 例为不确定。在这 69 例 HCWs 中，31 例（45%）在重复检测时出现逆转，31 例中有 25 例（80.6%）的逆转者 TST 阴性。在最初 QFT-GIT 阴性的 2232 名 HCWs 中，71 例（3.2%）在重复检测时出现转化。在这 71 例转化者中，有 41 例进行了第三次 QFT-GIT 检测，90%（37 例）逆转回阴性。只有 2 例 HCWs 出现 TST 和 QFT-GIT 转化。
IGRA 可重复性差和 QFT-GIT 转化的预测值低表明，在目前的解释标准下，QFT-GIT 不应用于美国 HCWs 的连续筛查。在结核病发病率低的情况下，连续检测 HCWs 时，TST 的可重复性高于 QFT-GIT。
