Automated electrochemiluminescence immunoassay for serum PlGF levels in women with singleton pregnancy at 9-13 weeks of gestation predicts preterm preeclampsia: a retrospective cohort study.

Our aims were to obtain the gestational-age-specific median of common logarithmic placental growth factor (PlGF) values in the first trimester in women with a singleton pregnancy in order to generate the gestational-age-specific multiple of the median (MoM) of log10PlGF at 9-13 weeks of gestation, to evaluate screening parameters of MoM of log10PlGF at 9-13 weeks of gestation to predict preterm preeclampsia (PE), and to construct an appropriate prediction model for preterm PE using minimum risk factors in multivariable logistic regression analyses in a retrospective sub-cohort study. Preterm PE occurred in 2.9% (20/700), and PE in 5.1% (36/700). Serum PlGF levels were measured using Elecsys PlGF®. MoMs of log10PlGF at 9-13 weeks of gestation in Japanese women with a singleton pregnancy followed a normal distribution. We determined the appropriate cut-off value of MoM of log10PlGF to predict preterm PE at around a10% false-positive rate (0.854). The MoM of log10PlGF < 0.854 yielded sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio (95% confidence interval [CI]), and negative likelihood ratio (95% CI) of 55.0%, 91.9%, 17.5%, 98.5%, 6.79 (4.22-10.91), and 0.49 (0.30-0.80), respectively. The combination of MoM of log10PlGF and presence of either chronic hypertension or history of PE/gestational hypertension (GH) yielded sensitivity and specificity of 80.0 and 85.7%, respectively, to predict preterm PE. In conclusion, the automated electrochemiluminescence immunoassay for serum PlGF levels in women with singleton pregnancy at 9-13 weeks of gestation may be useful to predict preterm PE.

Low placental growth factor levels and high soluble endoglin levels at 26-31 weeks of gestation precede light placenta with and without relatively heavy infant, respectively: A retrospective cohort study.

AIM: Our aim was to examine whether serum levels of placental growth factor (PlGF) and soluble endoglin (sEng) at 19-25 and 26-31 weeks of gestation were associated with the occurrence of the 9-block categorization of placenta weight (PW) and fetal/placenta ratio (F/P ratio). METHODS: We performed a retrospective cohort study in 1391 women with singleton pregnancy. Serum levels of PlGF and sEng were measured by enzyme immunosorbent assay. A light placenta was defined as PW ZS < -1.28 SD. Based on the PW (light, normal, and heavy) and F/P ratio (relatively heavy, balanced growth, and relatively small), 9-block categorization were performed. Multivariable logistic regression analyses were performed. RESULTS: Low PlGF at 26-31 weeks was an independent risk factor for the birth of infants belonging to Block A (light placenta and relatively heavy infant), after adjusting for prepregnancy body mass index and serum levels of sEng. High sEng at 26-31 weeks was an independent risk factor for the birth of infants belonging to Block D (light placenta and balanced growth of infant), after adjusting for past history of either preeclampsia or gestational hypertension, high pulsatility index of uterine artery flow velocity waveforms in the second trimester, and serum level of PlGF. CONCLUSIONS: Low PlGF levels at 26-31 weeks of gestation may precede a light placenta and relatively heavy infant (Block A), and high sEng levels at 26-31 weeks of gestation may precede a light placenta and balanced growth of infant (Block D).

Difficulty of predicting early-onset super-imposed preeclampsia in pregnant women with hemodialysis due to diabetic nephropathy by serum levels of sFlt-1, PlGF, and sEng.

There are few case reports in which circulating levels of soluble fms-like tyrosine kinase 1 (sFlt-1), placental growth factor (PlGF), and soluble endoglin (sEng) were measured before the onset of super-imposed preeclampsia in women with hemodialysis. A 40-year-old Japanese nulliparous women with hemodialysis due to diabetic nephropathy became pregnant by frozen embryo transfer. Intensive hemodialysis was started at 5 weeks of gestation. Her blood pressure (BP) in the first trimester was around 130/80 mmHg. At 20+3 weeks, she was admitted for close monitoring; her BP was 137/75 mmHg. Her BP increased to 157/88 mmHg at 31+2 weeks, and nifedipine at 20 mg/day was started at 31+6 weeks. However, the serial longitudinal measurements of sFlt-1, PlGF, and sEng did not predict the onset of super-imposed preeclampsia. Cesarean section was performed at 33+6 weeks due to uncontrollable hypertension. A healthy female infant weighing 2138 g was delivered. As for the changes of biomarkers between just before and just after hemodialysis, sFlt-1 was significantly higher just after compared with just before hemodialysis (5774 ± 1875 pg/mL vs. 2960 ± 905 pg/mL, respectively, p < 0.001). PlGF was also significantly higher just after compared with just before hemodialysis (2227 ± 1038 pg/mL vs. 1377 ± 614 pg/mL, respectively, p < 0.001). However, the sFlt-1/PlGF ratio and sEng levels were not significantly different between just before and just after hemodialysis (p = 0.115, p = 0.672, respectively). In conclusion, prediction of early-onset super-imposed preeclampsia using angiogenic and anti-angiogenic markers in pregnant women with hemodialysis might be difficult.

Temporary hypertension and white coat hypertension in the first trimester as risk factors for preeclampsia.

We compared the risk of preeclampsia (PE) among women with normal blood pressure (BP), high-normal BP, high BP, temporary hypertension (THT), white coat hypertension (WCH), and chronic hypertension (CH) in the first trimester. This was a retrospective cohort study involving 2858 pregnant women, who received regular maternal checkups at <12 weeks. BP levels were evaluated using the average of the second and third BP readings. When patients showed HT in the first trimester that later normalized during 14-19 weeks, we called this condition THT. BP levels were classified as normal BP, high-normal BP, high BP, THT, WCH, and CH. PE was defined as a new onset of HT after 20 weeks accompanied by either proteinuria or other organ dysfunctions. Gestational hypertension (GH) was defined as the new onset of HT after 20 weeks. The proportion of WCH in women with newly diagnosed HT was 47%. PE occurred in 1.3, 4.3, 8.1, 8.2, 14.3, and 25.0% of women with normal BP, high-normal BP, high BP, THT, WCH, and CH, respectively. GH occurred in 0.3, 1.8, 9.9, 2.0, and 28.6% of women with normal BP, high-normal BP, high BP, THT, and WCH, respectively. After adjusting for possible confounding variables, high-normal BP, high BP, THT, WCH, and CH were independent risk factors for PE vs. normal BP; in addition, high-normal BP, high BP/THT, and WCH were independent risk factors for GH vs. normal BP. In conclusion, THT and WCH in the first trimester were risk factors for PE, and WCH was a risk factor for GH.

Preeclamptic patient-derived circulating cell-free DNA activates the production of inflammatory cytokines via toll-like receptor 9 signalling in the human placenta.

OBJECTIVES: Preeclampsia, a pregnancy-specific syndrome, is associated with maternal systemic and placental inflammatory responses. Cell-free DNA (cfDNA) and cf-foetal DNA (cffDNA) in the blood are elevated in patients with preeclampsia and act as danger signals. Placenta-derived foetal DNA induces inflammatory responses and pregnancy complications in mice. However, whether extracellular DNA from the placenta really causes inflammatory responses remains unclear. Therefore, we investigated the effect of serum cfDNA and placental cffDNA on inflammatory responses using normal pregnant women and preeclampsia patients. METHODS: Sera were taken from normal pregnant women and preeclampsia patients, and human trophoblast cell line Sw.71 cells were treated with serum with or without toll-like receptor 9 (TLR9; a sensor of exogenous DNA) inhibitor and genome elimination reagent. For cffDNA collection, placental tissue from the participants was cultured, and the released cffDNA was administrated to Sw.71 cells. RESULTS: The amount of serum cfDNA was higher in preeclampsia patients than in normal pregnant women. Treatment of preeclampsia serum stimulated inflammatory cytokine secretion, which was inhibited by a genome elimination reagent. Expression levels of TLR9 and amount of cffDNA from the placenta were higher in preeclampsia patients than of normal pregnant women. Preeclampsia-derived cffDNA increased inflammatory cytokine levels compared with normal pregnant derived cffDNA. CONCLUSION: In human trophoblast cells, preeclampsia patient-derived cfDNA increased inflammatory cytokine levels via TLR9. Preeclampsia placenta released more cffDNA, which stimulated inflammatory cytokine. We suggest that elevated circulating cfDNA and cffDNA induces placental inflammatory responses, resulting in accelerated pathological features of preeclampsia.

Markedly higher sFlt-1/PlGF ratio in a woman with acute fatty liver of pregnancy compared with HELLP syndrome.

AIM: To compare serum levels of angiogenesis-related factors between 14 women with HELLP (hemolysis, elevated liver enzymes and low platelet count) syndrome and a woman with acute fatty liver of pregnancy (AFLP). METHODS: Serum samples were collected in 2004-2008 and 2013-2016. The levels of soluble fms-like tyrosine kinase 1 (sFlt-1) and placental growth factor (PlGF) were measured by an automated electrochemiluminescence immunoassay using Elecsys sFlt-1 and Elecsys PlGF. After logarithmic transformation, levels of sFlt-1, PlGF and the sFlt-1/PlGF ratio in a woman with AFLP were compared with those in women with HELLP syndrome, using the one-sample t-test. RESULTS: At 37 weeks of gestation, a patient was diagnosed with AFLP based on Swansea criteria (showing six features including elevated transaminases), and she also showed a duodenal ulcer with active bleeding, thrombocytopenia and hypertension. Her serum levels of sFlt-1 and sFlt-1/PlGF ratio were significantly higher than in those with HELLP syndrome (273 040 pg/mL vs 15 135 [mean], P < 0.001; 4236 vs 224, P < 0.001; respectively). However, her serum level of PlGF was not significantly different from those with HELLP syndrome. CONCLUSION: Serum levels of sFlt-1 and the sFlt-1/PlGF ratio, but not PlGF, in a woman with AFLP were markedly higher than those in women with HELLP syndrome. AFLP may be a different clinical entity from HELLP syndrome based on angiogenesis-related factors. Clinically, the sFlt-1/PlGF ratio may be used to rapidly distinguish AFLP from HELLP syndrome.

Clinical usefulness of serum levels of soluble fms-like tyrosine kinase 1/placental growth factor ratio to rule out preeclampsia in women with new-onset lupus nephritis during pregnancy.

Measurement of the soluble fms-like tyrosine kinase 1 (sFlt-1)/placental growth factor (PlGF) ratio may be clinically useful to discriminate systemic lupus erythematosus (SLE) from preeclampsia. Here, we present a pregnant woman with new-onset SLE with hypertension, with the measurement of the sFlt-1/PlGF ratio during pregnancy. A 31-year-old Japanese nulliparous woman, who had been diagnosed with idiopathic thrombocytopenic purpura at 10 years, had a systolic blood pressure of 120 mmHg and was negative for proteinuria at 12+1 weeks. Since her blood pressure increased to 159/86 mmHg with 3+ proteinuria at 25+4 weeks, preeclampsia was suspected. Deterioration of the kidney function (creatinine: 0.58 mg/dL at 24+6 weeks to 0.83 mg/dL at 33+6 weeks) necessitated cesarean section at 33+6 weeks. After delivery, she still showed increased creatinine and proteinuria. Therefore, she was transferred to a nephrology specialist in a tertiary center and was finally diagnosed with SLE with lupus nephritis class IV-G(A) (diffuse lupus nephritis). The serum levels of sFlt-1 and the sFlt-1/PlGF ratio, which are usually elevated in preeclampsia, were within normal reference ranges at 27+6, 28+1, and 28+6 weeks of gestation, although the serum levels of PlGF were slightly lower than the normal reference range. In conclusion, measurement of the sFlt-1/PlGF ratio may be clinically useful to discriminate lupus nephritis from preeclampsia.

Serum soluble LIGHT in the early third trimester as a novel biomarker for predicting late-onset preeclampsia.

Our aim was to evaluate whether serum levels of soluble LIGHT (sLIGHT) at 27-31 weeks can predict the later occurrence of gestational hypertension (GH), late-onset preeclampsia (PE), and early-onset PE. Mean blood pressure (MBP), soluble fma-like tyrosine kinase 1/placental growth factor (sFlt-1/PlGF) ratio at 27-31 weeks, and sLIGHT at 27-31 weeks were independent risk factors for late-onset PE. The combination of the three risk factors improved sensitivity with a false-positive rate of 10% (MBP: 60%, log10(sFlt-1/PlGF): 45%, sLIGHT: 35%, combination: 75%). Serum sLIGHT in the early third trimester may be a novel biomarker for predicting late-onset PE.

Vaginal Ureaplasma species increase chorioamnionitis in very preterm infants with preterm premature rupture of the membranes at < 28 weeks of gestation.

Our aim was to investigate the association between vaginal Ureaplasma species (spp.) and the subsequent occurrence of chorioamnionitis (CAM), perinatal death, neonatal morbidity, and long-term neurodevelopmental impairments (NDIs) at 3 years of age. We analyzed 55 pregnant women with singleton pregnancy who had preterm premature rupture of the membranes (pPROM) at < 28+0 weeks of gestation, and delivered between 22+0 and 31+6 weeks at our tertiary hospital in 2007-2016. NDIs were defined as either cerebral palsy or developmental delay evaluated at 1.5 and/or 3 years old. The presence of Ureaplasma spp. and Mycoplasma hominis were evaluated using urea-arginine broth and Mycoplasma PPLO Agar. The presence of Ureaplasma spp. in the vagina was positive in 41%. Vaginal Ureaplasma spp. was a significant risk factor for CAM; however, it was not significantly associated with the occurrence of perinatal death, pulmonary hypoplasia, respiratory distress syndrome, transient tachypnea of the newborn, intraventricular hemorrhage, periventricular leukomalacia, bronchopulmonary dysplasia defined as oxygen required and occasional ventilatory assistance required at week 36 as modified (BPD36), or NDIs. The crude odds ratio (95% confidence interval) of Ureaplasma spp. for the occurrence of CAM was 9.5 (1.10-82) (p = 0.041). In very preterm birth infants with pPROM, CAM, BPD36, and NDIs occurred in 78, 60, and 36%, respectively. Vaginal Ureaplasma spp. was a significant risk factor for CAM in very preterm birth infants with pPROM. The incidences of BPD36 and NDIs in such infants were very high, nearing 3/5 and 1/3, respectively.

Increased serum levels of sFlt-1/PlGF ratio in preeclamptic women with onset at <32 weeks compared with ≥32 weeks.

OBJECTIVE: Our first aim was to construct gestational-age-specific reference ranges of serum levels of soluble fms-like tyrosine kinase 1 (sFlt-1), placental growth factor (PlGF), and the sFlt-1/PlGF ratio at 19-38 weeks of gestation. Our second aim was to compare the serum levels of sFlt-1, PlGF, and the sFlt-1/PlGF ratio in 81 women with PE which occurred at <32, 32-33, 34-35, and ≥36 weeks. METHOD: Serum levels of sFlt-1 and PlGF were measured by automated immunoassays (Elecsys sFlt-1 and Elecsys PlGF). We constructed the normal reference ranges of log10sFlt-1, log10PlGF, and the log10(sFlt-1/PlGF) between 19 and 38 weeks using 309 samples, which could be represented by a quadratic curve. The cut-off levels were defined as the 5th and 95th percentiles of their gestational-age-specific reference ranges. RESULTS: The frequencies of high sFlt-1, low PlGF, and a high sFlt-1/PlGF ratio in women with an onset at <32 weeks were all 100%, whereas there were no groups showing 100% abnormalities of sFlt-1, PlGF or the sFlt-1/PlGF ratio in women with an onset at 32-33, 34-35, and ≥36 weeks. The levels of sFlt-1, PlGF, and the sFlt-1/PlGF ratio in women with an onset at <32 weeks were significantly different from those in women with an onset at ≥32-33 weeks, although the levels of sFlt-1, PlGF, and the sFlt-1/PlGF ratio in women with an onset at 32-33, 34-35, and ≥36 weeks were almost the same. CONCLUSION: The appropriate threshold weeks for defining early-onset PE might be 32+0 weeks rather than 34+0 or 36+0 weeks.

Galectin-1 as a novel risk factor for both gestational hypertension and preeclampsia, specifially its expression at a low level in the second trimester and a high level after onset.

Our aim was to evaluate whether the serum level of galectin-1 (Gal-1) at 18-24 and 27-31 weeks of gestation is a risk factor for predicting the later occurrence of not only preeclampsia (PE) but also gestational hypertension (GH). We measured serum levels of soluble fms-like tyrosine kinase 1 (sFlt-1), placental growth factor (PlGF), and Gal-1 using an enzyme-linked immunosorbent assay in 81 and 73 normal pregnant women, 22 and 16 women with a later onset of GH, and 37 and 29 women with a later onset of PE at 18-24 and 27-31 weeks, respectively. We also measured Gal-1 in 33 women with GH and 78 women with PE after the onset. The levels of Gal-1 after the onset of GH, late-onset PE (onset at ⩾34 weeks), and early-onset PE (onset at <34 weeks) were significantly higher than those in normal pregnant women at 27-31 weeks. However, the low levels of Gal-1 (<8.1 ng ml-1) at 18-24 weeks, but not at 27-31 weeks, predicted the later occurrence of not only early-onset PE and late-onset PE but also GH. The low level of Gal-1 at 18-24 weeks was an independent risk factor for the later occurrence of GH and PE, after adjusting for the effects of a high BP and increased sFlt-1/PlGF ratio at 18-24 weeks. In conclusion, the serum level of Gal-1 is a novel risk factor for both GH and PE, specifically its expression at a low level in the second trimester and a high level after onset.

Independent risk factors for a small placenta and a small-for-gestational-age infant at 35-41 weeks of gestation: An association with circulating angiogenesis-related factor levels at 19-31 weeks of gestation.

AIM: Our aim was to investigate the effects of angiogenesis-related factor levels at 19-25 and 26-31 weeks of gestation (WG) on the later occurrence of a small-for-gestational-age (SGA) placenta (small placenta) or an SGA infant delivered at 35-41 WG. METHODS: We measured plasma levels of soluble fms-like tyrosine kinase 1 (sFlt-1) and placental growth factor (PlGF), and the serum level of soluble endoglin (sEng) in 679 pregnant women with blood sampling at both 19-25 and 26-31 WG in a prospective study. A small placenta and an SGA infant were defined as <10th percentile, respectively. Multivariate logistic regression analyses were performed using maternal factors, a high mean pulsatility index (high mPI) of the uterine artery in the second trimester, and angiogenesis-related factor levels. RESULTS: Regarding the occurrence of a small placenta, low PlGF at 19-25 WG (adjusted odds ratio [95% confidence interval]: 2.4 [1.01-5.7]) and a high mPI (2.5 [1.4-4.3]) were independent risk factors. Moreover, low PlGF at 26-31 WG (3.3 [1.5-7.0]) was also an independent risk factor after adjusting for the effect of mPI. Concerning the occurrence of an SGA infant, a high mPI (2.8 [1.6-5.2]) and high sEng at 26-31 WG (2.3 [1.2-4.5]) were independent risk factors. CONCLUSION: Low levels of PlGF at 19-25 and 26-31 WG were independent risk factors for a small placenta at ≥35 WG; and a high sEng at 26-31 WG was an independent risk factor for an SGA infant at ≥35 WG.

Prediction and prevention of hypertensive disorders of pregnancy.

The most common classifications of hypertensive disorders of pregnancy consist of chronic hypertension, gestational hypertension, preeclampsia (PE) and superimposed PE. A common final pathophysiology of PE is endothelial dysfunction. The most successful translational research model for explaining the cause-effect relationship in the genesis of PE is the angiogenic/angiostatic balance theory, involving soluble fms-like tyrosine kinase 1 (sFlt-1), placental growth factor (PlGF) and soluble endoglin (sEng). In a systematic review of articles on the prediction of early-onset PE using angiogenesis-related factors, we revealed that the prediction of early-onset PE in the first trimester is clinically possible, but the prediction of early-onset PE in the early third trimester might be ideal. In addition, an onset threshold or a serial approach appeared to be clinically useful for predicting the imminent onset of PE, with onset at <4 weeks after blood sampling in the second and early third trimesters, because the positive likelihood ratio was >10 and the positive predictive value was >20%. The National Institute for Health and Care Excellence guidelines state that the Triage PlGF testing and Elecsys immunoassay for the sFlt-1/PlGF ratio could help to exclude PE in women with suspected PE at 20-34 weeks of gestation. Until now, we have not found any effective therapies to prevent PE. However, low-dose aspirin treatment starting at ⩽16 weeks of gestation might be associated with a marked reduction in PE. In addition, early statin treatment might prevent the occurrence of PE. Currently, a clinical trial using pravastatin for the prevention of PE is ongoing.

The Frequency of Peripheral Blood CD4+FoxP3+ Regulatory T Cells in Women With Pre-eclampsia and Those With High-risk Factors for Pre-eclampsia.

OBJECTIVE: We compared the frequency of peripheral blood Treg cells in women with pre-eclampsia (PE) and in those without, and investigated whether the frequency of Treg cells in women with high-risk factor for PE changed during pregnancy. METHODS: We examined the frequency of CD4+FoxP3+ Treg cells in the peripheral blood using flow cytometry. Eleven women with PE and 10 women without PE (controls) were included. Every control had any risk factors for PE, such as high blood pressure, bilateral notching or a past history of PE or gestational hypertension. Blood sampling was conducted 1-3 times in the controls. RESULTS: No significant differences were observed in the frequency of Treg cells between women with PE and the controls [mean ± SE (%): 5.74 ± 0.91 versus 5.48 ± 0.94, p = 0.843]. In five controls with serial sampling, the frequency of Treg cells significantly decreased from 5.83 ± 1.20 to 2.99 ± 0.54 (p = 0.046) (week of the first sampling to that of the last sampling [mean ± SD]: 21.5 ± 1.6 weeks to 31.2 ± 2.5 weeks). CONCLUSION: The frequency of Treg cells in women with PE was almost identical to that in the controls. The frequency of Treg cells in the controls was reduced by half from the second trimester to the third trimester. These results suggested that the levels of Treg cells in a high-risk pregnant cohort were decreased to those in women with PE in the third trimester irrespective of the occurrence of PE.

A novel three-step approach for predicting the imminent onset of preeclampsia within 4 weeks after blood sampling at 19-31 weeks of gestation.

Our aim was to develop a novel screening method to detect the imminent onset of preeclampsia (PE) within 4 weeks after blood sampling. We prospectively collected data regarding past history of PE/gestational hypertension (GH), blood pressure levels at 16-23 weeks and plasma levels of soluble fms-like tyrosine kinase 1 (sFlt-1) and placental growth factor (PlGF) twice at 19-31 weeks, which were measured using an automated electrochemiluminescence immunoassay. We found that a three-step approach by sequential selection using maternal factors, including a past history of PE/GH or blood pressure levels ≥120/80 mm Hg at 16-23 weeks (first step), followed by plasma levels of PlGF in the <5th percentile (second step) and plasma levels of sFlt-1 in the ≥95th percentile (third step) yielded both high sensitivity and specificity. The imminent onset of PE occurred in 2 of 1199 (0.2%) women recruited at 19-25 weeks and in 6 of 798 (0.8%) women recruited at 26-31 weeks. The sensitivity, specificity, positive likelihood ratio (95% confidence interval), negative likelihood ratio (95% confidence interval), positive predictive value and negative predictive value of the three-step approach for predicting the imminent onset of PE at 19-25 weeks were 100%, 99.8%, 599 (150-2390), 0%, 50% and 100%, respectively; and those at 26-31 weeks were 83%, 99.1%, 94 (42-214), 0.17 (0.03-1.01), 42% and 99.9%, respectively. In conclusion, the three-step approach is a highly sensitive and specific screening method for detecting the imminent onset of PE within 4 weeks after blood sampling at 19-31 weeks of gestation.

Additive effects of mean blood pressure and bilateral notching in the second trimester on subsequent angiogenesis-related factors.

It has not been clarified whether high mean blood pressure (HBP) of ≥90 mm Hg and bilateral notching (BN) on uterine artery Doppler additively affect the subsequent circulating levels of placental growth factor (PlGF), soluble fms-like tyrosine kinase 1 (sFlt-1) and soluble endoglin (sEng). Serum levels of PlGF, sFlt-1 and sEng at 17-25 weeks and 26-32 weeks were measured in all women with HBP+BN- (n=272), HBP-BN+ (n=130) and HBP+BN+ (n=60) in 1239 eligible women, and 338 consecutive women with HBP-BN- were selected from the remaining 777 women. Only data before the onset of preeclampsia were evaluated. The cutoff value of an abnormal decrease of PlGF was set at the 5th percentile, and those of an abnormal increase of sFlt-1, sFlt-1/PlGF and sEng were set at the 95th percentile. The frequency of HBP in those with BN- was almost the same as that in those with BN+ (25.9% vs. 26.7%). In women with HBP-BN-, HBP-BN+, HBP+BN- and HBP+BN+, the frequency of abnormal sFlt-1/PlGF ratio at 26-32 weeks was 6.6%, 9.2%, 14.4% and 22.8%, respectively; and the frequency of abnormal sFlt-1/PlGF ratio at 26-32 weeks in those with HBP+BN+ was significantly increased than in HBP-BN-. Similarly, in the four groups, the frequency of abnormal sEng at 26-32 weeks was 5.4%, 2.5%, 12.2% and 19.0%, respectively; and the frequency in those with HBP+BN+ was significantly increased than in HBP-BN-. In conclusion, high BP levels and abnormal uterine artery Doppler may be additively implicated in circulating abnormalities of angiogenesis-related factors.

A trio of risk factors for the onset of preeclampsia in the second and early third trimesters.

OBJECTIVE: We evaluated the biological interaction among mean blood pressure (MBP), uterine artery Doppler (UAD), and the soluble fms-like tyrosine kinase 1 (sFlt-1)/placental growth factor (PlGF) ratio for preeclampsia (PE) risk. STUDY DESIGN: A prospective cohort study. MAIN OUTCOME MEASURES: In 1239 pregnant women, MBP and UAD were measured at 16-23weeks of gestation, and plasma levels of the sFlt-1/PlGF ratio at 19-25weeks and 26-31weeks. A Cox proportional hazard model was used. Women with a low sFlt-1/PlGF ratio and either low BP or normal UAD were set as controls. The relative excess risk due to biological interaction (RERI) was calculated using the following equation: RERI=hazard ratio (HR) in women with high sFlt-1/PlGF and both high BP and abnormal UAD (group 3) - HR in women with both high BP and abnormal UAD alone (group 1) - HR in women with high sFlt-1/PlGF alone (group 2)+1. RERI⩾10 was considered to be strong. RESULTS: At 19-25weeks, the HR and 95% confidence intervals (CI) in group 1, group 2, and group 3 were 7.4 (3.1-17.4), 15.3 (4.5-52.2), and 107.0 (41.0-279), respectively, and the RERI for PE was 85.3. At 26-31weeks, the HR and 95% CI in each group were 8.3 (2.9-23.2), 7.5 (0.97-57.8), and 69.0 (18.5-256), respectively; the RERI for PE was 54.2. CONCLUSIONS: We found a trio of risk factors for the onset of PE in the second and early third trimesters: high BP, abnormal UAD, and high sFlt-1/PlGF ratio.

Increased antiangiogenetic factors in severe proteinuria without hypertension in pregnancy: is kidney biopsy necessary?

Acute onset of severe proteinuria during pregnancy obliges physicians to clinically discriminate between gestational proteinuria (GP) and new onset of nephritis. A multiparous woman developed severe proteinuria (5.8 g/day) without hypertension at 32 weeks of gestation. We measured the maternal level of soluble fms-like tyrosine kinase 1 (sFlt-1) and soluble endoglin (sEng), which were extremely high (41.3 and 54.8 ng/ml, respectively), leading us to consider this condition as GP rather than acute onset of nephritis. Thus, we did not perform a kidney biopsy and did not administer a steroid agent. Non-reassuring fetal status required emergency Cesarean section at 33 weeks. Proteinuria decreased to 0.36 g/day at 12 weeks after delivery, and finally disappeared 26 weeks postpartum. Measurement of sFlt-1 and sEng in a pregnant woman with severe proteinuria without hypertension may assist in differential diagnosis of GP from acute onset of nephritis, and thus help to decide whether to perform kidney biopsy during pregnancy.

Onset threshold of the plasma levels of soluble fms-like tyrosine kinase 1/placental growth factor ratio for predicting the imminent onset of preeclampsia within 4 weeks after blood sampling at 19-31 weeks of gestation.

Our aim was to evaluate the onset threshold of plasma levels of the soluble fms-like tyrosine kinase 1 (sFlt-1)/placental growth factor (PlGF) ratio for predicting the imminent onset of preeclampsia (PE) within 4 weeks after blood sampling. We prospectively measured the plasma levels of sFlt-1 and PlGF by an automated electrochemiluminescence immunoassay at 19-25 weeks of gestation in 1199 women and at 26-31 weeks of gestation in 798 women. The onset threshold of the sFlt-1/PlGF ratio was determined as the 2.5th percentile of the 95th confidence interval (CI) of a regression line between the onset gestational weeks of PE and the standard deviation score of log10(sFlt-1/PlGF), using 25 samples taken within 1 week after the onset of PE. The imminent onset of PE was identified in 2 (0.2%) women recruited at 19-25 weeks and in 6 (0.8%) women recruited at 26-31 weeks. The onset threshold of plasma levels of the sFlt-1/PlGF ratio at 19-25 weeks showed a sensitivity (SE) of 1.00, a specificity (SP) of 1.00, a positive likelihood ratio (LR+) of ∞ and a positive predictive value (PPV) of 1.00; the onset threshold of plasma levels of the sFlt-1/PlGF ratio at 26-31 weeks showed a SE of 0.83, a SP of 0.994, a LR+ of 132 (95% CI: 51-339) and a PPV of 0.50. In conclusion, the onset threshold of plasma levels of the sFlt-1/PlGF ratio was shown to be a highly sensitive and a highly specific screening method for detecting the imminent onset of PE within 4 weeks after blood sampling at 19-31 weeks.