Mathad Jyoti S, Bhosale Ramesh, Sangar Vikrant, Mave Vidya, Gupte Nikhil, Kanade Savita, Nangude Ashwini, Chopade Kavita, Suryavanshi Nishi, Deshpande Prasad, Kulkarni Vandana, Glesby Marshall J, Fitzgerald Daniel, Bharadwaj Renu, Sambarey Pradeep, Gupta Amita
Division of Infectious Diseases, Weill Cornell Medical College, New York, New York, United States of America.
Department of Obstetrics and Gynaecology, Byramjee Jeejeebhoy Government Medical College- Sassoon General Hospital, Pune, Maharashtra, India.
PLoS One. 2014 Mar 21;9(3):e92308. doi: 10.1371/journal.pone.0092308. eCollection 2014.
Targeted screening for latent TB infection (LTBI) in vulnerable populations is a recommended TB control strategy. Pregnant women are at high risk for developing TB and likely to access healthcare, making pregnancy an important screening opportunity in developing countries. The sensitivity of the widely-used tuberculin skin test (TST), however, may be reduced during pregnancy.
We performed a cross-sectional study comparing the TST with the QuantiFERON Gold In-tube (QGIT) in 401 HIV-negative women presenting antepartum (n = 154), at delivery (n = 148), or postpartum (n = 99) to a government hospital in Pune, India. A subset of 60 women enrolled during pregnancy was followed longitudinally and received both tests at all three stages of pregnancy.
The QGIT returned significantly more positive results than the TST. Of the 401 women in the cross-sectional study, 150 (37%) had a positive QGIT, compared to 59 (14%) for the TST (p<0.005). Forty-nine (12%) did not have their TST read. Of 356 who had both results available, 46 (13%) were concordant positive, 91 (25%) were discordant (12 (3%) TST+/QGIT-; 79 (22%) TST-/QGIT+), and 206 (57%) concordant negative. Comparison by stage of pregnancy revealed that QGIT percent positivity remained stable between antepartum and delivery, unlike TST results (QGIT 31-32% vs TST 11-17%). Median IFN-γ concentration was lower at delivery than in antepartum or postpartum (1.66 vs 2.65 vs 8.99 IU/mL, p = 0.001). During postpartum, both tests had significantly increased positives (QGIT 31% vs 32% vs 52%, p = 0.01; TST 17% vs 11% vs 25%, p<0.005). The same trends were observed in the longitudinal subset.
Timing and choice of LTBI test during pregnancy impact results. QGIT was more stable and more closely approximated the LTBI prevalence in India. But pregnancy stage clearly affects both tests, raising important questions about how the complex immune changes brought on by pregnancy may impact LTBI screening.
对弱势群体进行潜伏性结核感染（LTBI）的针对性筛查是一项推荐的结核病控制策略。孕妇患结核病的风险很高，且可能会寻求医疗保健服务，这使得怀孕成为发展中国家一个重要的筛查时机。然而，广泛使用的结核菌素皮肤试验（TST）在孕期的敏感性可能会降低。
我们开展了一项横断面研究，在印度浦那一家政府医院对401名HIV阴性的女性进行了TST与全血γ-干扰素释放试验（QGIT）的比较，这些女性在产前（n = 154）、分娩时（n = 148）或产后（n = 99）就诊。对孕期入组的60名女性进行了纵向随访，并在孕期的三个阶段都接受了这两种检测。
QGIT检测出的阳性结果显著多于TST。在横断面研究的401名女性中，150名（37%）QGIT检测为阳性，而TST检测为阳性的有59名（14%）（p<0.005）。49名（12%）女性的TST结果未被读取。在356名两种检测结果都有的女性中，46名（13%）结果一致为阳性，91名（25%）结果不一致（12名（3%）TST阳性/QGIT阴性；79名（22%）TST阴性/QGIT阳性），206名（57%）结果一致为阴性。按怀孕阶段进行比较发现，QGIT的阳性率在产前和分娩时保持稳定，与TST结果不同（QGIT为31%-32%，而TST为11%-17%）。分娩时的IFN-γ浓度中位数低于产前或产后（1.66 vs 2.65 vs 8.99 IU/mL，p = 0.001）。产后，两种检测的阳性率均显著增加（QGIT为31% vs 32% vs 52%，p = 0.01；TST为17% vs 11% vs 25%，p<0.005）。在纵向随访的子集中也观察到了相同的趋势。
孕期LTBI检测的时间和选择会影响结果。QGIT更稳定，更接近印度LTBI的流行率。但怀孕阶段显然会影响这两种检测，这就引发了关于怀孕带来的复杂免疫变化如何影响LTBI筛查的重要问题。
