Occupational Health Division, Alameda Professor Hernâni Monteiro, Hospital S. João, Porto, Portugal.
Eur Respir J. 2009 Dec;34(6):1423-8. doi: 10.1183/09031936.00053809.
The prevalence of latent tuberculosis (TB) infection (LTBI) and the incidence of active tuberculosis in healthcare workers (HCWs) in a Portuguese hospital were examined. This cross-sectional study comprises 4,735 hospital workers screened between May 2005 and September 2008. Tuberculin skin test (TST) and interferon-gamma release assay (IGRA) were used simultaneously in 1,219 HCWs (25.7%). Radiographs were taken in symptomatic HCWs or in test-positive HCWs. The tests were repeated annually or bi-annually depending on risk assessment. IGRA was positive in 32.6% and TST in 74.2% of the HCWs. Years spent in healthcare were a risk factor for a positive IGRA, but not for a positive TST. Repeated bacillus Calmette-Guérin vaccination increased the probability of TST+/IGRA- discordance (35.4% versus 54.4%, respectively). In those tested three times with TST during the study period (n = 59), the mean diameter of TST increased from 5 to 7 to 10 mm. Within 3 yrs, 31 HCWs were diagnosed with active TB (annual incidence rate 191 out of 100,000 people). In eight HCWs with active TB, TST and IGRA were performed at the time of diagnosis and each test was positive. TB burden in HCWs in Portugal is high. With IGRA, the number of radiographs needed to exclude active TB could have been reduced by about half without missing a case of active TB. Therefore IGRA should be introduced into TB screening programmes.
本研究旨在调查葡萄牙一家医院内医护工作者（HCWs）中潜伏性结核感染（LTBI）的流行率和活动性结核病的发生率。该横断面研究共纳入了 4735 名于 2005 年 5 月至 2008 年 9 月期间接受筛查的医院工作者。1219 名 HCWs（25.7%）同时接受了结核菌素皮肤试验（TST）和干扰素-γ释放试验（IGRA）检测。有症状的 HCWs 或 TST 阳性的 HCWs 行 X 线检查。根据风险评估，每年或每两年重复一次检测。IGRA 阳性率为 32.6%，TST 阳性率为 74.2%。在 HCWs 中，从事医疗工作的年限是 IGRA 阳性的一个危险因素，但不是 TST 阳性的一个危险因素。重复的卡介苗接种增加了 TST+/IGRA-不相符的概率（分别为 35.4%和 54.4%）。在研究期间接受三次 TST 检测的 59 名患者中，TST 的平均直径从 5 毫米增加到 7 毫米，再增加到 10 毫米。在 3 年内，31 名 HCWs 被诊断患有活动性结核病（年发病率为每 100000 人 191 例）。在 8 名患有活动性结核病的 HCWs 中，在诊断时进行了 TST 和 IGRA 检测，两种检测均为阳性。葡萄牙 HCWs 的结核负担很高。如果使用 IGRA，可将排除活动性结核病所需的 X 射线数量减少约一半，同时不会漏诊活动性结核病。因此，IGRA 应被引入结核病筛查计划。
