Buhimschi Catalin S, Sfakianaki Anna K, Hamar Benjamin G, Pettker Christian M, Bahtiyar Mert-Ozan, Funai Edmund, Norwitz Errol R, Copel Joshua A, Lockwood Charles J, Buhimschi Irina A
Department of Obstetrics, Gynecology, and Reproductive Science, Yale University, New Haven, CT 06520, USA.
Am J Obstet Gynecol. 2006 Feb;194(2):309-16. doi: 10.1016/j.ajog.2005.07.070.
We sought to identify the use of vaginal amniotic fluid (vAF) glucose measurements in predicting infection of the amniotic fluid retrieved by transabdominal amniocentesis (aAF) in women with preterm premature rupture of the membranes (PPROM).
Fluid was retrieved by aAF was retreived from 35 consecutive women with PPROM on whom an amniocentesis was clinically indicated to rule out intra-amniotic infection/inflammation and successfully completed. aAF was cultured for aerobic, anaerobic bacteria, Ureaplasma and Mycoplasma species. Clinical laboratory analysis for aAF included glucose concentration, Gram stain, lactate dehydrogenase, and white and red blood cell count. vAF was analyzed only for glucose concentration. Glucose concentration for the paired abdominal-vaginal AF samples (aAF-vAF) was determined by using well-established clinical and research laboratory methods. At the end of enrollment we stratified our patients into 2 groups: (1) positive microbial cultures (+)AFC (n = 17, gestational age [GA]: 27.3 +/- 0.7 weeks) or (2) negative microbial cultures (-)AFC (n = 18, GA: 31.3 +/- 0.5 weeks). Cohen kappa measure of concordance and receiver operating characteristic (ROC) curve analysis were used to test the ability of the vaginal "pool" glucose measurements to discriminate between women with positive or negative AF cultures.
Women with (+)AFC ruptured and delivered at an earlier GA compared with the (-)AFC group (p < .001). The latency period was similar (P = .35). There was a significant linear correlation between aAF and vAF glucose concentrations (r = 0.783, P < .001). Women with intra-amniotic infection (IAI) had significantly lower aAF [mean +/- SEM (+)AFC: 11.4 +/- 3.2 vs (-)AFC 23.0 +/- 2.8 mg/dL, P = .01] and vAF glucose levels [(+)AFC: 10.1 +/- 2.8 vs (-)AFC: 19.8 +/- 2.9 mg/dL, P = .02] compared with the noninfected group. Cohen kappa measure of concordance indicated "substantial" agreement between aAF and vAF glucose measurements (kappa = 0.719, 95% CI = 0.491-0.947). The sensitivity of the vAF glucose level to detect IAI ranged from 82% to 47%, whereas specificity ranged from 100% to 56% depending on the threshold we used. A vaginal "pool" (vAF) glucose measurement less than 5 mg/dL had 47.1% sensitivity, 100% specificity, 100% positive predictive value, 66.7% negative predictive value, and 74.2% accuracy in identifying women with (+)AFC.
Vaginal glucose determination is a readily available, inexpensive, rapid AF marker that can be measured practically in any clinical laboratory. vAF glucose measurements less than 5 mg/dL have predictive value, but low sensitivity for detection of IAI.
我们试图确定阴道羊水（vAF）葡萄糖测量在预测胎膜早破（PPROM）女性经腹羊膜腔穿刺术（aAF）获取的羊水感染中的应用。
从35例连续的PPROM女性中通过aAF获取羊水，临床上对这些女性进行羊膜腔穿刺术以排除羊膜腔内感染/炎症且均成功完成。对aAF进行需氧菌、厌氧菌、解脲脲原体和支原体培养。aAF的临床实验室分析包括葡萄糖浓度、革兰氏染色、乳酸脱氢酶以及白细胞和红细胞计数。仅对vAF分析葡萄糖浓度。通过成熟的临床和研究实验室方法测定配对的腹 -阴道羊水样本（aAF - vAF）的葡萄糖浓度。在入组结束时，我们将患者分为2组：（1）微生物培养阳性（+）AFC组（n = 17，孕周[GA]：27.3±0.7周）或（2）微生物培养阴性（ - ）AFC组（n = 18，GA：31.3±0.5周）。使用Cohen kappa一致性度量和受试者操作特征（ROC）曲线分析来测试阴道“池”葡萄糖测量区分羊水培养阳性或阴性女性的能力。
与（ - ）AFC组相比，（ + ）AFC组女性在更早的孕周发生胎膜破裂和分娩（p <.001）。潜伏期相似（P =.35）。aAF和vAF葡萄糖浓度之间存在显著的线性相关性（r = 0.783，P <.001）。与未感染组相比，羊膜腔内感染（IAI）女性的aAF [平均±标准误（ + ）AFC组：11.4±3.2 vs（ - ）AFC组23.0±2.8 mg/dL，P =.01]和vAF葡萄糖水平[（ + ）AFC组：10.1±2.8 vs（ - ）AFC组：19.8±2.9 mg/dL，P =.02]显著更低。Cohen kappa一致性度量表明aAF和vAF葡萄糖测量之间存在“高度”一致性（kappa = 0.719，95％CI = 0.491 - 0.947）。vAF葡萄糖水平检测IAI的敏感性范围为82％至47％，而特异性范围为100％至56％，具体取决于我们使用的阈值。阴道“池”（vAF）葡萄糖测量小于5 mg/dL在识别（ + ）AFC女性时具有47.1％的敏感性、100％的特异性、100％的阳性预测值、66.7％的阴性预测值和74.2％的准确性。
阴道葡萄糖测定是一种易于获得、成本低廉、快速的羊水标志物，几乎可以在任何临床实验室进行测量。vAF葡萄糖测量小于5 mg/dL具有预测价值，但检测IAI的敏感性较低。
