Prediction of Early- and Late-Onset Pre-Eclampsia in the Preclinical Stage via Placenta-Specific Extracellular miRNA Profiling

Pre-eclampsia (PE) is one of the severe complications of pregnancy in 3-8% of all cases and is one of the leading causes of maternal and perinatal mortality. The fundamental role in the pathogenesis of PE is assigned to maternal and/or placental factors, whereby the combination and manifestation of which determines the time of onset of the clinical symptoms of PE (before or after 34 weeks of gestation) and their severity. It is known that the expression level of miRNAs, the regulators of signaling cascades in the cell, depends on gestational age. In the present study, we focused on the identification of the placenta-specific miRNAs that differentiate between early- and late-onset pre-eclampsia (ePE and lPE) throughout pregnancy, from the first to the third trimester. A total of 67 patients were analyzed using small RNA deep sequencing and real-time quantitative PCR, which resulted in a core list of miRNAs (let-7b-5p, let-7d-3p, let-7f-5p, let-7i-5p, miR-22-5p, miR-451a, miR-1246, miR-30e-5p, miR-20a-5p, miR-1307-3p, and miR-320e), which in certain combinations can predict ePE or lPE with 100% sensitivity and 84-100% specificity in the 1st trimester of pregnancy. According to the literature data, these miRNA predictors of PE control trophoblast proliferation, invasion, migration, syncytialization, the endoplasmic reticulum unfolded protein response, immune tolerance, angiogenesis, and vascular integrity. The simultaneous detection of let-7d-3p, miR-451a, and miR-1307-3p, resistant to the repeated freezing/thawing of blood serum samples, in combination with biochemical (b-hCG and PAPP-A) and ultrasound (UAPI) parameters, allowed us to develop a universal model for the prediction of ePE and lPE onset (FPR = 15.7% and FNR = 9.5%), which was validated using a test cohort of 48 patients and demonstrated false-positive results in 26.7% of cases and false negatives in 5.6% of cases. For comparison, the use of the generally accepted Astraia program in the analysis of the test cohort of patients led to worse results: FPR = 62.1% and FNR = 33.3%.

Placental histological patterns and uterine artery Doppler velocimetry in pregnancies complicated by early or late pre-eclampsia

OBJECTIVES

To study placental patterns in pregnancies complicated by pre-eclampsia (PE) and to verify whether the findings are related to gestational age (GA) at PE onset and second-trimester uterine artery (UtA) Doppler.

METHODS

For all pre-eclamptic women who delivered between January 2010 and December 2013, we collected retrospectively data related to placental findings and UtA Doppler velocimetry performed at PE onset. The study cohort was divided into groups according to early-onset (EO) or late-onset (LO) PE. Regression analysis was performed to test the ability of UtA Doppler velocimetry to predict subsequent development of placental lesions, after correcting for possible confounders.

RESULTS

Placental abnormalities occurred with a significantly lower incidence in the LO-PE group (n = 72) than in the EO-PE group (n = 105) (P = 0.02). Irrespective of GA at PE onset, UtA pulsatility index (PI) was able to predict macroscopic infarctions (P = 0.001), distal villous hypoplasia (P = 0.03), decidual arteriolopathy (P = 0.03), villous infarcts (P < 0.001), syncytiotrophoblast 'knots' (P = 0.02), microcalcifications (P = 0.02), perivillous fibrin deposition (P = 0.02) and placental hemorrhage (P = 0.01).

CONCLUSIONS

Similar placental abnormalities were present in both EO-PE and LO-PE groups, although with quantitative differences according to GA and UtA Doppler velocimetry at PE onset. Histological patterns were predicted by UtA-PI, independently of GA, supporting the use of UtA Doppler velocimetry as the key criterion in PE classification. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.