Kusanovic Juan Pedro, Romero Roberto, Mazaki-Tovi Shali, Chaiworapongsa Tinnakorn, Mittal Pooja, Gotsch Francesca, Erez Offer, Vaisbuch Edi, Edwin Samuel S, Than Nandor Gabor, Camacho Natalia, Pacora Percy, Rogers Wade, Hassan Sonia S
Perinatology Research Branch, NICHD/NIH/DHHS, Wayne State University/HutzelWomen's Hospital, Detroit, MI 48201, USA.
J Matern Fetal Neonatal Med. 2008 Dec;21(12):902-16. doi: 10.1080/14767050802320357.
Intra-amniotic infection/inflammation (IAI) is one of the most important mechanisms of disease in preterm birth. Resistin is an adipocytokine that has been linked to insulin resistance, diabetes, obesity and inflammation. The objective of this study was to determine if resistin is present in amniotic fluid (AF) and if its concentration changes with gestational age, in the presence of labour, and in IAI in patients with spontaneous preterm labour (PTL) and intact membranes, preterm prelabour rupture of membranes (PPROM) and clinical chorioamnionitis.
This cross-sectional study included 648 patients in the following groups: (1) women in the mid-trimester of pregnancy (14-18 weeks) who underwent amniocentesis for genetic indications and delivered a normal neonate at term (n = 61); (2) normal pregnant women at term with (n = 49) and without (n = 50) spontaneous labour; (3) patients with an episode of PTL and intact membranes who were classified into: (a) PTL who delivered at term (n = 153); (b) PTL who delivered preterm (<37 weeks gestation) without IAI (n = 108); and (c) PTL with IAI (n = 84); (4) women with PPROM with (n = 47) and without (n = 44) IAI; and (5) patients with clinical chorioamnionitis at term with (n = 22) and without (n = 30) microbial invasion of the amniotic cavity. Resistin concentration in AF was determined by enzyme-linked immunoassay. Non-parametric statistics were used for analyses.
(1) Resistin was detected in all AF samples; (2) the median AF resistin concentration at term was significantly higher than in the mid-trimester (23.6 ng/mL vs. 10 ng/mL; p < 0.001); (3) among patients with PTL, the median AF resistin concentration was significantly higher in patients with IAI than in those without IAI (144.9 ng/mL vs. 18.7 ng/mL; p < 0.001) and those with PTL and intact membranes who delivered at term (144.9 ng/mL vs. 16.3 ng/mL; p < 0.001); (4) patients with PPROM with IAI had a significantly higher median AF resistin concentration than those without IAI (132.6 ng/mL vs. 13 ng/mL; p < 0.001); (5) no significant differences were observed in the median AF resistin concentration between patients with spontaneous labour at term and those at term not in labour (28.7 ng/mL vs. 23.6 ng/mL; p = 0.07); and (6) AF resistin concentration > or =37 ng/mL (derived from a receiver-operating characteristic curve) had a sensitivity of 85.4% and a specificity of 94.3% for the diagnosis of intra-amniotic inflammation.
Resistin is a physiologic constituent of the AF, and its concentrations in AF: (1) are significantly elevated in the presence of IAI; (2) increase with advancing gestation; and (3) do not change in the presence of spontaneous labour at term. We propose that resistin may play a role in the innate immune response against intra-amniotic infection.
羊膜腔内感染/炎症（IAI）是早产最重要的发病机制之一。抵抗素是一种脂肪细胞因子，与胰岛素抵抗、糖尿病、肥胖和炎症相关。本研究的目的是确定抵抗素是否存在于羊水（AF）中，以及其浓度是否随孕周、临产情况以及胎膜完整的自发性早产（PTL）、胎膜早破早产（PPROM）和临床绒毛膜羊膜炎患者的IAI而变化。
这项横断面研究纳入了648例患者，分为以下几组：（1）妊娠中期（14 - 18周）因遗传指征接受羊膜腔穿刺并足月分娩正常新生儿的女性（n = 61）；（2）足月有（n = 49）和无（n = 50）自发性临产的正常孕妇；（3）有PTL且胎膜完整的患者，分为：（a）足月分娩的PTL患者（n = 153）；（b）未发生IAI的早产（孕周<37周）PTL患者（n = 108）；（c）发生IAI的PTL患者（n = 84）；（4）有和无IAI的PPROM女性；（5）足月有和无羊膜腔微生物入侵的临床绒毛膜羊膜炎患者。通过酶联免疫吸附测定法测定AF中的抵抗素浓度。采用非参数统计进行分析。
（1）在所有AF样本中均检测到抵抗素；（2）足月时AF抵抗素浓度中位数显著高于妊娠中期（23.6 ng/mL对10 ng/mL；p < 0.001）；（3）在PTL患者中，发生IAI患者的AF抵抗素浓度中位数显著高于未发生IAI患者（144.9 ng/mL对18.7 ng/mL；p < 0.001）以及足月分娩的胎膜完整的PTL患者（144.9 ng/mL对16.3 ng/mL；p < 0.001）；（4）发生IAI的PPROM患者的AF抵抗素浓度中位数显著高于未发生IAI患者（132.6 ng/mL对13 ng/mL；p < 0.001）；（5）足月自发性临产患者与未临产患者的AF抵抗素浓度中位数无显著差异（28.7 ng/mL对23.6 ng/mL；p = 0.07）；（6）AF抵抗素浓度≥37 ng/mL（源自受试者工作特征曲线）对羊膜腔内炎症诊断的敏感度为85.4%，特异度为94.3%。
抵抗素是AF的一种生理成分，其在AF中的浓度：（1）在IAI存在时显著升高；（2）随孕周增加而升高；（3）在足月自发性临产时无变化。我们认为抵抗素可能在针对羊膜腔内感染的固有免疫反应中起作用。
