Background An imbalance in circulating angiogenic factors plays a central role in the pathogenesis of preeclampsia. Methods and Results We prospectively studied 616 women who were evaluated for suspected preeclampsia. We measured plasma levels of antiangiogenic soluble fms-like tyrosine kinase 1 (sFlt1) and proangiogenic placental growth factor (PlGF) at presentation, and examined for an association between sFlt1/PlGF ratio and subsequent adverse maternal and perinatal outcomes within 2 weeks. The median [25th–75th centile] sFlt1/PlGF ratio at presentation was elevated in participants who experienced any adverse outcome compared to those who did not (47.0 [15.5–112.2] versus 10.8 [4.1–28.6], p<0.0001). Among those presenting <34 weeks (N=167), the results were more striking (226.6 [50.4–547.3] versus 4.5 [2.0–13.5], p<0.0001), and the risk was markedly elevated when the highest sFlt1/PlGF ratio tertile was compared to the lowest (OR 47.8, 95% CI 14.6–156.6). Among participants presenting at <34 weeks, the addition of sFlt1/PlGF ratio to hypertension and proteinuria significantly improved the prediction for subsequent adverse outcomes (AUC=0.93 for hypertension, proteinuria, and sFlt1/PlGF versus AUC=0.84 for hypertension and proteinuria alone; P=0.001). Delivery occurred within two weeks of presentation in 86.0% of women with sFlt1/PlGF ratio ≥ 85 compared with 15.8% of women with sFlt1/PlGF ratio <85 (HR 15.2, 95% CI 8.0–28.7). Conclusions In women with suspected preeclampsia presenting at <34 weeks, circulating sFlt1/PlGF ratio predicts adverse outcomes occurring within two weeks. The accuracy of this test is substantially better than current approaches and may be useful in risk stratification and management. Additional studies are warranted to validate these findings.

Objective-The objective of this study was to compare the clinical characteristics and outcomes of preeclamptic women presenting with a normal plasma angiogenic profile with those subjects that are characterized by an abnormal angiogenic profile.Methods-This was a secondary analysis of a prospective cohort study in women presenting to obstetrical triage at <37 weeks of gestation and diagnosed with preeclampsia within 2 weeks of enrollment and in whom angiogenic factors (sFlt1 and PlGF) measurements were available. Patients were divided into two groups based on their circulating levels of these factors described as a ratio the sFlt1/PlGF ratio, non-angiogenic preeclampsia (sFlt1/PlGF ratio <85) and angiogenic preeclampsia (sFlt1/PlGF ratio ≥85). The data are presented by sFlt1/PlGF category using median and quartile 1-quartile 3 for continuous variables and by frequency and sample sizes for categorical variables. Verlohren has served as a consultant to Roche Diagnostics. Dr. Thadhani is a co-inventor on patents related to the prediction of preeclampsia that has been out licensed to diagnostic companies and has financial interest in Aggamin LLC. Dr. Karumanchi is a coinventor of multiple patents related to angiogenic proteins for the diagnosis and therapy of preeclampsia. These patents have been licensed to multiple companies. Dr. Karumanchi reports having served as a consultant to Roche and Beckman Coulter and has financial interest in Aggamin LLC. The remaining authors report no conflicts. Interestingly, delivery between 34-37 weeks and resource utilization (hospital admission days) were similar in the two groups. NIH Public AccessConclusion-In contrast to the angiogenic form, the non-angiogenic form of preeclampsia is characterized by little to no risk of preeclampsia related adverse outcomes, other than iatrogenic prematurity. Incorporation of angiogenic biomarkers in the evaluation of preeclampsia may allow accurate and early identification of severe disease.

This article reports the development of an optical imaging technique, confocal light absorption and scattering spectroscopic (CLASS) microscopy, capable of noninvasively determining the dimensions and other physical properties of single subcellular organelles. CLASS microscopy combines the principles of lightscattering spectroscopy (LSS) with confocal microscopy. LSS is an optical technique that relates the spectroscopic properties of light elastically scattered by small particles to their size, refractive index, and shape. The multispectral nature of LSS enables it to measure internal cell structures much smaller than the diffraction limit without damaging the cell or requiring exogenous markers, which could affect cell function. Scanning the confocal volume across the sample creates an image. CLASS microscopy approaches the accuracy of electron microscopy but is nondestructive and does not require the contrast agents common to optical microscopy. It provides unique capabilities to study functions of viable cells, which are beyond the capabilities of other techniques.light-scattering spectroscopy ͉ submicrometer ͉ native contrast ͉ imaging ͉ refractive index