Chaemsaithong Piya, Romero Roberto, Korzeniewski Steven J, Martinez-Varea Alicia, Dong Zhong, Yoon Bo Hyun, Hassan Sonia S, Chaiworapongsa Tinnakorn, Yeo Lami
a Division of Intramural Research , Perinatology Research Branch, Program for Perinatal Research and Obstetrics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH , Detroit , MI , USA .
b Department of Obstetrics and Gynecology , Wayne State University , Detroit , MI , USA .
J Matern Fetal Neonatal Med. 2016;29(3):360-7. doi: 10.3109/14767058.2015.1006621. Epub 2015 Mar 23.
Preterm prelabor rupture of membranes (preterm PROM) accounts for 30-40% of spontaneous preterm deliveries and thus is a major contributor to perinatal morbidity and mortality. An amniotic fluid (AF) interleukin-6 (IL-6) concentration is a key cytokine for the identification of intra-amniotic inflammation, patients at risk of impending preterm delivery and adverse pregnancy complications. The conventional method to determine IL-6 concentrations in AF is an enzyme-linked immunosorbent assay (ELISA). However, this technique is not available in clinical settings, and the results may take several days. A lateral flow-based immunoassay, or point of care (POC) test, has been developed to address this issue. The objective of this study was to compare the performance of AF IL-6 determined by the POC test to that determined by ELISA for the identification of intra-amniotic inflammation in patients with preterm PROM.
This retrospective cohort study includes 56 women with singleton pregnancies who presented with preterm PROM. Amniocentesis was performed at the time of diagnosis, and AF was analyzed using cultivation techniques for aerobic and anaerobic bacteria as well as genital mycoplasmas. AF Gram stain and AF white blood cell counts were determined. AF IL-6 concentrations were measured using both lateral flow-based immunoassay and ELISA. The primary outcome was intra-amniotic inflammation defined as AF ELISA IL-6 ≥ 2600 pg/ml. A previously determined cut-off of 745 pg/ml was used to define a positive POC test.
(1) The POC test for AF IL-6 concentrations had 97% sensitivity and 96% specificity for the identification of intra-amniotic inflammation, as defined using ELISA among patients with preterm PROM and (2) the diagnostic performance of the POC test for IL-6 was strongly correlated to that of an ELISA test for the identification of intra-amniotic inflammation and was equivalent for the identification of acute inflammatory placental lesions and microbial invasion of the amniotic cavity (MIAC).
A POC AF IL-6 test can identify intra-amniotic inflammation in patients with preterm PROM. Results can be available within 20 min - this makes it possible to implement interventions designed to treat intra-amniotic inflammation and improve pregnancy outcomes.
胎膜早破（preterm PROM）占自发性早产的30%-40%，因此是围产期发病和死亡的主要原因。羊水（AF）白细胞介素-6（IL-6）浓度是识别羊膜腔内炎症、有即将早产风险的患者及不良妊娠并发症的关键细胞因子。测定AF中IL-6浓度的传统方法是酶联免疫吸附测定（ELISA）。然而，该技术在临床环境中无法使用，且结果可能需要几天时间。已开发出一种基于侧向流动的免疫测定法，即即时检验（POC）测试，以解决这一问题。本研究的目的是比较POC测试测定的AF IL-6与ELISA测定的AF IL-6在识别早产胎膜早破患者羊膜腔内炎症方面的性能。
这项回顾性队列研究纳入了56名单胎妊娠且出现早产胎膜早破的女性。在诊断时进行羊膜穿刺术，并使用需氧菌、厌氧菌以及生殖支原体的培养技术对羊水进行分析。测定羊水革兰氏染色和羊水白细胞计数。使用基于侧向流动的免疫测定法和ELISA测定羊水IL-6浓度。主要结局是羊膜腔内炎症，定义为AF ELISA IL-6≥2600 pg/ml。先前确定的745 pg/ml的临界值用于定义POC测试阳性。
（1）对于早产胎膜早破患者中使用ELISA定义的羊膜腔内炎症，AF IL-6浓度的POC测试具有97%的敏感性和96%的特异性；（2）POC测试对IL-6的诊断性能与ELISA测试在识别羊膜腔内炎症方面密切相关，在识别急性炎症性胎盘病变和羊膜腔微生物入侵（MIAC）方面相当。
POC羊水IL-6测试可识别早产胎膜早破患者的羊膜腔内炎症。20分钟内即可获得结果——这使得实施旨在治疗羊膜腔内炎症并改善妊娠结局的干预措施成为可能。
