Resistance to activated protein C and impaired TFPI activity in women with previous hormone-induced venous thromboembolism.

INTRODUCTION: Hormonal contraception is a well-known risk factor for venous thromboembolism (VTE). APC resistance and impaired functions of protein S and TFPI are thought to play an important role in the pathogenesis of hormone-related VTE. It is unknown, whether women, who develop VTE during hormonal contraception possess a vulnerability in these pathways, making them susceptible to thrombosis. MATERIALS AND METHODS: Plasma samples were obtained from 57 premenopausal women in average 15.3 years after hormone-associated VTE and from 31 healthy controls. Thrombin generation at high tissue factor (TF) in the absence and in the presence of activated protein C (APC) and at low TF without and with inhibiting anti-protein S- and anti-TFPI-antibodies was measured via calibrated automated thrombography. RESULTS: Women with previous hormone-related thrombosis had higher thrombin generation at low TF, higher APC resistance, protein S- and TFPI ratios, differences: 219.9 nM IIa.min (95%CI:90.4 to 349.3); 1.88 (95%CI:0.71 to 3.05); 0.13 (95%CI:0.01 to 0.26) and 0.19 (95%CI:0.08 to 0.30), respectively. Thrombin generation at high TF without APC did not differ between the groups. Smoking decreased thrombin generation at low TF by -222.6 nM IIa.min (95%CI: -381.1 to -64.1), the APC sensitivity ratio by -2.20 (95%CI: -3.63 to -0.77) and the TFPI ratio by -0.16 (95%CI: -0.29 to -0.03), but did not influence thrombin generation at high TF. DISCUSSION: We demonstrated impairment of the protein S/TFPI system and increased APC resistance in women with previous hormone-induced VTE. Smoking decreased thrombin generation at assay conditions, dependent on the function of the TFPI system.

Obstetric outcomes in patients with primary thrombotic and obstetric antiphospholipid syndrome and its relation to the antiphospholipid antibody profile.

Introduction: Previous studies suggested different obstetric outcomes between patients with thrombotic or obstetric antiphospholipid syndrome, but the data are inconclusive. Aims: To investigate obstetric outcomes and their relation to the antiphospholipid antibody profile in primary thrombotic or obstetric antiphospholipid syndrome patients and compare those to a control population. Materials and methods: A retrospective single-centre study on a cohort of 30 pregnant women with primary antiphospholipid syndrome treated at Karolinska University Hospital Solna, Sweden between 2000 and 2016. The pregnancy outcomes were compared to the outcomes of all pregnancies in Stockholm County during the same period. Results: Preeclampsia (p < 0.001), low birth weight at delivery (p = 0.001), Apgar < 7 at 5 minutes (p < 0.001) and small infants (p < 0.001) were more common in antiphospholipid syndrome patients compared to controls. Obstetric antiphospholipid syndrome patients had a higher incidence of small infants (p = 0.023), lower birth weight (p = 0.013) and infants born with complications (p=0.004) compared to thrombotic antiphospholipid syndrome. Mothers with triple antibody positivity had a higher incidence of preeclampsia (p = 0.03), preterm delivery (p = 0.011), small infants (p=0.002) and infants born with complications (p = 0.012). Conclusions: Patients with primary antiphospholipid syndrome, especially those with obstetric antiphospholipid syndrome and triple antibody positivity, are at higher risk for adverse pregnancy outcomes, even under antithrombotic treatment. More frequent antenatal controls in high-risk patients can further improve outcomes.

Pregnancy-associated plasma protein-A is positively correlated with first-trimester skin microvascular reactivity.

OBJECTIVE: To investigate the relationship between levels of circulating maternal pregnancy-associated plasma protein-A (PAPP-A) and first-trimester maternal vascular function. METHODS: This was a cross-sectional study of 53 healthy, non-smoking, nulliparous pregnant women in Stockholm, Sweden. PAPP-A levels and vascular function were assessed during gestational weeks 11-14. Forearm skin microcirculation was investigated by laser Doppler perfusion imaging during iontophoresis of acetylcholine (ACh) and sodium nitroprusside (SNP) to assess endothelium-dependent and -independent microvascular vasodilatation, respectively. Microvascular endothelial function index was calculated as peak ACh/peak SNP. Endothelium-dependent and -independent vasodilatation in the brachial artery was evaluated, respectively, by postischemic hyperemia-induced flow-mediated vasodilatation (FMD) and by response to sublingual intake of glyceryl trinitrate (GTN). RESULTS: PAPP-A was correlated with skin microvascular endothelial function index (ß = 1.008 (95% CI, 0.34-1.68), r2  = 0.17, P = 0.004). PAPP-A also correlated inversely with FMD (ß = -0.052 (95% CI, -0.094 to -0.011), r2  = 0.13, P = 0.014) but did not relate to forearm endothelial function index (i.e. FMD/GTN). The results were retained in multivariate analyses including known confounding factors. CONCLUSIONS: First-trimester endothelium-dependent skin microvascular reactivity was positively related to PAPP-A levels. If confirmed, these novel findings suggest that first-trimester skin microvascular reactivity could be a useful early pregnancy marker of placental function. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Longitudinal study of vascular structure and function during normal pregnancy.

OBJECTIVE: To examine alterations in maternal vascular structure and function during normal pregnancy. METHODS: We assessed brachial and central blood pressure, pulse-wave velocity and augmentation index (by pulse-wave analysis and applanation tonometry), common carotid artery structure (by ultrasonography) and endothelial function in the brachial artery (by postischemic hyperemia-induced flow-mediated vasodilatation by glyceryl trinitrate) and in the forearm skin microcirculation (by laser Doppler perfusion imaging during iontophoretic administration of acetylcholine and sodium nitroprusside) in 52 healthy nulliparous women at 14, 24 and 34 weeks' gestation, and at 9 months postpartum. RESULTS: During pregnancy, brachial and central systolic and diastolic blood pressures initially decreased but subsequently increased (all P < 0.05). Flow-mediated vasodilatation in the brachial artery increased during early pregnancy (P < 0.05), whereas non-specific vasodilatation by glyceryl trinitrate decreased (P < 0.01), indicating improved endothelial function. Thus, endothelial function index (forearm blood flow/glyceryl trinitrate) increased during pregnancy (0.30 ± 0.18 in the non-pregnant state at 9 months postpartum and 0.51 ± 0.19, 0.61 ± 0.39 and 0.49 ± 0.30 in the first, second and third trimesters, respectively) (P < 0.001). Endothelium-dependent skin microvascular reactivity to acetylcholine also increased (P < 0.01). Carotid-femoral pulse-wave velocity decreased during pregnancy (5.88 ± 0.91 m/s in the non-pregnant state and 5.55 ± 0.67, 5.12 ± 0.66 and 5.62 ± 0.74 m/s in the first, second and third trimesters, respectively) (P < 0.001). CONCLUSION: During normal pregnancy, the blood volume expansion necessary for sufficient fetal growth is accommodated by early and marked changes in the matvascular system. This seems to be dependent on normal adaptive endothelial and vascular function. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Fetal growth is associated with first-trimester maternal vascular function.

OBJECTIVE: To investigate the relationship between maternal endothelial function in the first trimester, assessed in both the brachial artery and the forearm skin microcirculation, and fetal growth. METHODS: Vascular function was assessed in 56 pregnant women during gestational weeks 11-14. Vascular reactivity in the brachial artery was evaluated by postischemic hyperemia-induced flow-mediated vasodilatation (FMD) and by vasodilatation following administration of sublingual glyceryl trinitrate (GTN). Forearm skin microcirculation was investigated by laser Doppler perfusion imaging during iontophoresis of acetylcholine (ACh) and sodium nitroprusside (SNP) to assess endothelium-dependent and -independent microvascular vasodilatation, respectively. Fetal growth was measured at study inclusion and birth-weight centile was calculated after delivery. RESULTS: FMD and GTN-induced vasodilatation were both associated with birth-weight centile. On multivariate analysis (adjusted for brachial artery diameter at rest, blood pressure, maternal age and heart rate), for FMD ß = 1.7 (95% CI, 0.06-3.34), r2 = 0.26 and P = 0.042, and for GTN-induced vasodilatation ß = 2.6 (95% CI, 0.44-4.68), r2 = 0.15 and P = 0.02. Endothelium-dependent and -independent microvascular reactivity were also associated with birth-weight centile: for ACh ß = 7.82 (95% CI, 1.81-13.83), r2 = 0.12 and P = 0.029, and for SNP ß = 6.27 (95% CI, 1.20-11.34), r2 = 0.11 and P = 0.016. CONCLUSION: First-trimester maternal vascular dilatation capacity (rather than endothelial function alone) is associated with fetal growth. These findings were consistent in both the brachial artery and the forearm skin microcirculation. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Changes in haemostatic parameters during the menstrual cycle and subsequent use of drospirenone-containing oral contraceptives.

INTRODUCTION: Oral contraceptives (OC) increase the risk of venous thromboembolism that depends on the OC formulation and could at least partially be explained by impaired function of the protein C-system (APC resistance) and the tissue factor pathway inhibitor (TFPI)-system. There is limited information available on the effects of OC, containing a newer progestogen- drospirenone (DRSP-OC) on these two major anticoagulant pathways, thrombin generation, reflecting the overall state of coagulation, and other coagulation parameters. METHODS: In a study population consisting of 14 healthy women (age 21-33 years) we investigated the effect of the menstrual cycle and subsequent use of DRSP-OC on APC resistance, the function of the TFPI-system, thrombin generation and on their major determinants, i.e. prothrombin, antithrombin, FV, FX, FVIII, protein C, protein S(total and free) and TFPI(full-length and free). RESULTS: All studied parameters remained unchanged during the menstrual cycle. During DRSP-OC use we observed a significant increase in APC resistance (~2.4-fold), thrombin generation measured at low (~2.2-fold) and high tissue factor concentrations (~1.4-fold), plasma concentrations of prothrombin (19%), FX (31%), FVIII (17%) and protein C (43%). DRSP-OC use impaired the function of the TFPI-system and decreased plasma levels of antithrombin (-6%), FV (-22%), protein Stotal (-21%), protein Sfree (-20%), TFPIfull-length (-36%) and TFPIfree (-46%). CONCLUSIONS: DRSP-OC caused procoagulant changes in all studied haemostatic parameters. The impairment of the protein C- and TFPI-systems was more pronounced than the impairment of the coagulation pathways and can at least partially account for the increased risk of venous thromboembolism in users of DRSP-OC.

Endogenous thrombin potential is higher during the luteal phase than during the follicular phase of a normal menstrual cycle.

STUDY QUESTION: Do thrombin generation and haemostatic parameters differ during the two phases of the menstrual cycle? SUMMARY ANSWER: Total thrombin concentration is higher during the luteal phase compared with the follicular phase of the menstrual cycle. WHAT IS KNOWN ALREADY: The coagulation cascade is affected by many variables, such as fluctuations in the levels of sex hormones. The studies on the variations in haemostatic parameters during the menstrual cycle have produced diverse results. STUDY DESIGN, SIZE, DURATION: Thrombin generation and selected haemostatic parameters (fibrinogen, factor II, factor VII, factor VIII, factor X, von Willebrand factor, antithrombin and D-dimer) were measured during the two phases of a normal menstrual cycle in 102 healthy women not taking any form of hormone medication. PARTICIPANTS/MATERIALS, SETTING, METHODS: The study cohort consisted of 102 healthy women with regular menstrual cycles. Thrombin generation was measured by the calibrated automated thrombogram method. Progesterone and sex hormone-binding globulin were measured by chemiluminescence enzyme immunoassays. Estradiol was measured by a sensitive radioimmunoassay. Fibrinogen was measured by a clotting method, antithrombin was measured by a chromogenic method and factor II, factor VII, factor VIII, factor X, von Willebrand factor and D-dimer were measured by photometric methods. MAIN RESULTS AND THE ROLE OF CHANCE: It was shown that the total amount of generated thrombin (Endogenous Thrombin Potential) was significantly higher during the luteal compared with the follicular phase (P = 0.027). Factor X was significantly higher during the follicular phase (P = 0.028). Progesterone exhibited significant associations (measured by the least squares regression analysis) with fibrinogen and factor X during the follicular phase (P = 0.043 and P = 0.033, respectively) and with factors II and VII during the luteal phase (P = 0.034 and P = 0.024, respectively). The validity of the results from the regression analysis was further confirmed by performing correlation analyses (Pearson correlation matrix) for haemostatic markers for the luteal and follicular phases (accepted correlation level >0.8). LIMITATIONS, REASONS FOR CAUTION: The wide confidence interval for the differences in endogenous thrombin potential during the two phases could imply that the size of the cohort may not be sufficient to fully evaluate the biological variations. Additionally, the haemostatic markers were not shown to have significant associations with thrombin generation, suggesting that the increased thrombin concentration during the luteal phase would be mediated by another mechanism, as yet unidentified. WIDER IMPLICATIONS OF THE FINDINGS: The associations between progesterone and the haemostatic markers, as shown for both phases of the menstrual cycle, suggest a previously unknown or undefined yet potentially significant role for progesterone in the coagulation system. However, it has been shown that the use of progestogen-only preparations does not affect the coagulation system, which is partly the reason why they are considered safe for women with thrombophilia or previous thrombotic event. Further studies are required in order to demonstrate whether our results can be extrapolated for synthetic progestins, which might have significant implication on the indications for their use.

Peripheral monocyte expression of the chemokine receptors CCR2, CCR5 and CXCR3 is altered at parturition in healthy women and in women with systemic lupus erythematosus.

Monocytes are precursors of macrophages and recruited to the uterus throughout pregnancy to perform important immunological functions. In this study, we hypothesized that pregnant women have reduced peripheral monocyte expression of chemokine receptors and alterations in PBMC responses to microbial stimuli as an adaption to pregnancy and that these changes are less pronounced in women with autoimmunity. We therefore investigated the chemokine receptor expression, migratory behaviour and responses to microbial stimulation of peripheral monocytes from pregnant women at parturition (n = 13) and from non-pregnant women (n = 9). In addition, we compared healthy pregnant women with women suffering from SLE (n = 5), a condition with pronounced systemic inflammation increasing the risk for pregnancy complications. We demonstrate that peripheral monocytes are affected by pregnancy with reduced percentages of CCR2+, CCR5+ and CXCR3+ monocytes of both classical (CD16-) and inflammatory (CD16+) subsets and that the trophoblast-secreted chemokine CCL2/MCP-1 recruited monocytes of both subsets in vitro. Further, PBMCs from pregnant women had a divergent response to microbial stimulation with lower CCL5/RANTES and higher CCL2/MCP-1 secretion compared with non-pregnant women. In addition, pregnant women had lower basal PBMC-secretion of CCL5/RANTES and higher basal secretion of IL-10 and CCL2/MCP-1. Interestingly, the women with SLE responded similar to pregnancy as did healthy women with lower percentages of CCR2+, CCR5+ and CXCR3+ monocytes. However, they had increased expression of CCR5 on CD16+ monocytes and heightened PBMC-secretion of CCL5/RANTES. In conclusion, our data indicate that monocyte chemokine receptor expression and the chemokine milieu during pregnancy are tightly regulated to support pregnancy.

Studies of microparticles in patients with the antiphospholipid syndrome (APS).

OBJECTIVES: To study circulating platelet, monocyte and endothelial microparticles (PMPs, MMPs and EMPs) in patients with antiphospholipid syndrome (APS) in comparison with healthy controls. MATERIAL AND METHOD: Fifty-two patients with APS and 52 healthy controls were investigated. MPs were measured on a flow cytometer (Beckman Gallios) and defined as particles sized < 1.0 µm, negative to phalloidin, positive to lactadherin and positive to either CD42a (PMPs), CD144 (EMPs) or CD14 (MMPs). Exposure of CD142 (TF) was measured on CD144 positive MPs. RESULTS: Total number of MPs (i.e. lactadherin positive particles) was higher in APS patients versus controls (p < 0.001). An increased number of EMPs (p < 0.001), increased TF-positive EMPs (p < 0.001) and increased MMPs (p < 0.001) were also observed. PMP numbers did not differ between the groups. None of the MP types differed in numbers between obstetric and thrombotic APS patients. CONCLUSION: We observed a high number of EMPs expressing TF in APS patients. The numbers of MMPs and total EMPs were also higher as compared with healthy controls but in contrast to previous reports, the number of PMPs did not differ between groups.

Pregnancy-associated inflammatory markers are elevated in pregnant women with systemic lupus erythematosus.

During normal pregnancy a dampening in T cell-mediated immunity is compensated by an increased pro-inflammatory activity. Likewise, the autoimmune disease systemic lupus erythematosus (SLE) is associated with inflammatory activity and pregnancy complications occur frequently in women with SLE. The aim of this study was to elucidate how SLE influences the chemokine and cytokine balance during and after pregnancy. Blood samples were taken from pregnant women with or without SLE at second and third trimester and 8-12 weeks after pregnancy. Cytokines (interleukin (IL)-1ß, IL-2, IL-4, IL-6, IL-10, IL-12p70, IL-17A, TNF, IFN-γ and IFN-α), chemokines (CXCL8/IL-8, CXCL9/MIG, CXCL10/IP-10, CCL2/MCP-1, CCL5/RANTES and CCL17/TARC), soluble IL-6 receptor (sIL-6R) and soluble glycoprotein 130 (gp130) were measured in serum using cytometric bead array (CBA) or enzyme-linked immunosorbent assay (ELISA). Women with SLE had increased serum concentrations of CXCL8/IL-8, CXCL9/MIG, CXCL10/IP-10 and IL-10 compared to controls both during and after pregnancy. Further, when dividing the patients based on disease activity, the women with active disease had the highest levels. Importantly, women with SLE seemed to respond to pregnancy in a similar way as controls, since the changes of cytokines and chemokines over the course of pregnancy were similar but with overall higher levels in the patient group. In conclusion, changes in pro- and anti-inflammatory serum components during pregnancy in women with SLE, occurring on top of already more pro-inflammatory levels, might increase their risk for pregnancy complications and flares. How their children are affected by this heightened inflammatory milieu during pregnancy needs further investigation.

The APC-PCI concentration as an early marker of activation of blood coagulation: a study of women on combined oral contraceptives.

BACKGROUND: The risk of venous tromboembolism (VTE) in women taking combined oral contraceptives (COCs) is attributed to changes in coagulation and fibrinolysis. The impact of the COCs may be greater in women with preexisting thrombophilic defects. Nevertheless most women who suffer from venous thrombosis do not have any of the well known hereditary or acquired risk factors. A simple and sensitive marker of"thrombogenicity" has not been identified. OBJECTIVES: To investigate the effects of two different monophasic combined oral contraceptives (COCs) on the plasma concentrations of activated protein C-inhibitor of protein C ( APC-PCI) and on comparable hemostatic factors in fertile women. METHOD: Forty four healthy nulliparous women with regular menstrual periods were included and randomly assigned to start with a monophasic preparation containing 30µg ethinylestradiol and 150µg levonogestrel (LNG/EE) or a preparation containing 30µg ethinylestradiol and 150 ug desogestrel (DG/EE). After a wash out period of two months, treatment with the alternate preparation was initiated and continued for two more cycles. RESULTS: The plasma concentration of the APC-PCI complex and thrombin-antithrombin complex (TAT) increased during treatment with the two COCs. During DG/EE treatment the APC-PCI complex increased significantly more than during LNG/EE (p<0,01).The plasma concentration of D-dimer did not increase during OC treatment. CONCLUSION: The APC-PCI complex concentration, which serves as a marker for thrombin generation and indicates hypercoagulability, was increased during COC treatment compared to baseline. The method is a sufficiently sensitive marker to detect even small differences in the activation of coagulation.

Thrombin generation and activated protein C resistance in the absence of factor V Leiden correlates with the risk of recurrent venous thromboembolism in women aged 18-65 years.

Identification of patients at high risk of recurrence after a first event of venous thromboembolism (VTE) remains difficult. Resistance to activated protein C (APC) is a known risk factor for VTE, but data on the risk of recurrence is controversial. We wanted to investigate whether APC resistance in the absence of factor V Leiden, determined with global coagulation test such as the thrombin generation assay, could be used as a marker for increased risk of recurrent VTE among women 18-65 years old after a first event of VTE. In a cohort of 243 women with a first event of VTE, plasma was collected after discontinuation of anticoagulant treatment and the patients were followed up for 46 months (median). Thrombin generation was measured via calibrated automated thrombography, at 1 pM and 10 pM of tissue factor (TF). In women without factor V Leiden (n=117), samples were analysed in the absence and in the presence of APC. Increase in ETP (endogenous thrombin potential) and peak height analysed in the presence of APC correlated significantly with higher risk of recurrence. At 1 pM, peak height correlated with increased risk of recurrence. In conclusion, high thrombin generation in the presence of APC, in women after a first event of VTE is indicative for an increased risk of a recurrence. We also found that thrombin generation at low TF (1 pM) is correlated with the risk of recurrence. Our data suggest that APC resistance in the absence of factor V Leiden is a risk factor for recurrent VTE.

Antimicrobial resistance in colonizing group B Streptococci before the implementation of a Swedish intrapartum antibiotic prophylaxis program.

The prevalence of antibiotic resistance and their genetic determinants in colonizing group B streptococci (GBS) sampled in a Swedish nationwide survey was examined. In five GBS isolates (1.3%), kanamycin/amikacin resistance and the presence of the aphA-3 gene was identified. Three of these isolates carried the aad-6 gene and were streptomycin-resistant. Screening with kanamycin and streptomycin 1,000-µg disks enabled a rapid and easy detection of these isolates. In all, 312/396 (79%) GBS were tetracycline-resistant and 95% of the examined isolates harbored the tetM gene. Among the 22 (5.5%) GBS resistant to erythromycin and/or clindamycin, the ermB gene was detected in nine isolates (41%) and erm(A/TR) in ten isolates (45%). A high level of erythromycin and clindamycin resistance with minimum inhibitory concentrations (MICs) >256 mg/L was found in four serotype V isolates that harbored ermB. The erythromycin/clindamycin resistance was distributed among all of the common serotypes Ia, Ib, II, III, IV, and V, but was not present in any of the 44 serotype III isolates associated to clonal complex 17. Screening for penicillin resistance with 1-µg oxacillin disks showed a homogenous population with a mean inhibition zone of 20 mm. A change in the present oxacillin breakpoints for GBS is suggested.

Maternal allergic disease does not affect the phenotype of T and B cells or the immune response to allergens in neonates.

BACKGROUND: It is hypothesized that the in utero environment in allergic mothers can affect the neonatal immune responses. The aim of this study was to analyse the effect of maternal allergic disease on cord blood mononuclear cell (CBMC) phenotype and proliferative responses upon allergen stimulation. METHODS: Peripheral blood mononuclear cells (PBMC) from 12 allergic and 14 nonallergic mothers and CBMC from their children were analysed. In the mothers, we determined cell proliferation, production of IL-4 and expression of FOXP3 in response to allergen stimulation. In the children, we evaluated cell proliferation and FOXP3 expression following allergen stimulation. Furthermore, expression of different homing markers on T cells and regulatory T cells and maturity of the T cells and B cell subsets were evaluated directly ex vivo. RESULTS: The timothy- and birch-allergic mothers responded with increased proliferation and/or IL-4 production towards timothy and birch extract, respectively, when compared to nonallergic mothers. This could not be explained by impairment of FOXP3(+) regulatory T cells in the allergic mothers. CBMC proliferation and FOXP3 expression in response to allergens were not affected by the allergic status of the mother. Also, phenotype of T cells, FOXP3(+) regulatory T cells and B cells was not affected by the allergic status of the mother. CONCLUSION: Our results suggest that maternal allergic disease has no effect on the neonatal response to allergens or the phenotype of neonatal lymphocytes. The factors studied here could, however, still affect later development of allergy.

Anti-Ro52/SSA antibody-exposed fetuses with prolonged atrioventricular time intervals show signs of decreased cardiac performance.

OBJECTIVE: To investigate if anti-Ro/SSA antibody-exposed fetuses with prolonged atrioventricular (AV) time intervals also have prolongation of the isovolumetric contraction time (ICT). METHODS: Seventy-eight anti-Ro/SSA (including 70 anti-Ro52) antibody-exposed fetuses at risk for congenital heart block (CHB) were followed weekly, between 18 and 24 weeks of gestation, with two Doppler echocardiographic methods designed to detect signs of first-degree AV block. One of these AV time measurements, using hemodynamic events from the mitral valve and aortic outflow as indirect markers of atrial and ventricular depolarization (MV-Ao), was also used to calculate a time interval representing an early phase of systolic cardiac performance, i.e. the ICT. Two hundred and eighty-four women with normal pregnancies served as controls for AV time intervals and another 106 were used to establish an ICT reference range. RESULTS: Strong positive relationships were found between ICT and MV-Ao time intervals (r = 0.91, P < 0.001), as well as between ICT and time intervals obtained from the superior vena cava and aorta (r = 0.85, P < 0.001). The ICT was estimated to contribute more than 50% of the total AV time prolongation. Abnormal AV time and ICT intervals were only seen in anti-Ro52 positive pregnancies. CONCLUSIONS: The ICT is an important contributor to prolongation of AV time intervals. This observation suggests that anti-Ro52/SSA antibody-exposed fetal hearts have not only disturbed electrical conduction but also decreased mechanical performance. Moreover, our findings have implications for the interpretation of AV time intervals used for surveillance of fetuses at risk for developing CHB.

Serologic follow-up of children born to mothers with Ro/SSA autoantibodies.

Neonatal lupus erythematosus (NLE) develops in foetuses of mothers with Ro/SSA and La/SSB antibodies and may include foetal atrioventricular block and dermatologic manifestations. In this study, we investigated postnatal Ro and La IgG, IgA and IgM antibody levels up to 1 year of age in 32 children born to Ro/SSA positive mothers. Antibody levels were correlated with NLE manifestations, and the role of breast feeding in transfer of autoantibodies from mother to child was evaluated. Ro52, Ro60 and La IgG antibodies all transferred from the mothers to their foetus in utero and were present in the infant at birth as detected by enzyme-linked immunosorbent assay using recombinant antigens and a synthetic peptide. A significant decrease in Ro52, Ro60 and La IgG autoantibody levels of the infants was observed from birth to 4-5 weeks of age (P < 0.05, P < 0.05 and P < 0.01). Ro- and La-specific IgA and IgM antibodies were detected in the serum from a subset of mothers. However, Ro- and La-specific IgA and IgM antibody levels were low or non-detectable in children raised both with and without breastfeeding. Furthermore, NLE skin lesions developed independently of breastfeeding. Our findings support a role for placental materno-foetal transfer of IgG autoantibodies in the pathogenesis of NLE and indicate that refraining from breastfeeding does not protect from NLE skin involvement.

Increased levels of an apoptotic product in the sera from women with pre-eclampsia.

Pre-eclampsia is associated with both maternal and foetal complications. Several studies have shown increased trophoblast apoptosis in the placenta of women with this condition. The aim of this study was to investigate whether increased apoptosis can be detected as elevated levels of an apoptotic product in serum samples from women with pre-eclampsia. For this purpose, we used the M30-Apoptosense ELISA assay, which measures a neo-epitope of cytokeratin 18 that is exposed after cleavage by caspases during apoptosis of epithelial cells (M30 antigen). The M30-antigen concentrations were measured in the sera of 15 healthy pregnant women and 15 patients with pre-eclampsia (gestation weeks 24-34). Patients with pre-eclampsia had significantly higher serum M30-antigen concentrations, median 120 U/L, compared to 15 healthy pregnant women matched for pregnancy length, median 104 U/L (p = 0.01). This is consistent with previous findings of increased trophoblast apoptosis in women with pre-eclampsia and raises the possibility that M30-antigen can be used as a serum marker for the severeness of this condition for the mother and child.

Increased thrombin generation in women with a history of preeclampsia.

INTRODUCTION: Women with a history of preeclampsia have an increased risk for cardiovascular disease in later life. We evaluated thrombogenic characteristics of women with a previous history of preeclampsia, expressed in levels of thrombin generation, number of microparticles and related to menstrual cycle and endothelial function, measured as flow-mediated dilatation. MATERIALS AND METHODS: We included 18 primipara women with a history of preeclampsia and 17 healthy primipara controls, 15 (+/-3) months after the index pregnancy. Thrombin generation was measured by tissue factor triggered assay, microparticle levels were measured by flow cytometry and the endothelial function was previously examined by measuring flow-mediated dilatation by high-resolution ultrasound, during follicular and luteal phases of the menstrual cycle. RESULTS: Women with previous preeclampsia produced more total amount of thrombin as calculated from thrombin max, thrombin potential and max slope levels p<0.05, 0.01 and 0.01 respectively. Platelet derived microparticle levels were higher in women with a history of preeclampsia, p=0.07. Flow-mediated dilatation was significantly decreased in comparison to healthy controls (p<0.0001). There were no variation in levels of thrombin, microparticles and flow-mediated dilatation during the menstrual phases. CONCLUSION: Women with a history of preeclampsia show signs of hypercoagulability as indicated by higher thrombin generation and higher platelet derived microparticle levels. Since these women were investigated more than one year after delivery, these results may be indicative of an increased risk of cardiovascular events later in life.

Antibodies to amino acid 200-239 (p200) of Ro52 as serological markers for the risk of developing congenital heart block.

Maternal autoantibodies to the p200-epitope of Ro52 have been suggested to correlate with development of congenital heart block. The aim of the present study was to evaluate the clinical relevance and predictive value of p200-antibodies in high-risk pregnancies. Sera from 515 Finnish, Swedish and American women were included in the study. Sera originated from 202 mothers with an infant affected by second- or third-degree atrioventricular block (AVB), 177 mothers with rheumatic disease having infants with normal heart rate and female blood donors (n = 136). A novel serological assay for Ro52 p200-antibodies with intra- and inter-assay variability of 3% and 3.8% respectively was developed. Mothers of children affected by AVB II-III had significantly higher p200-antibody levels than mothers with rheumatic disease having children with normal heart rate (P < 0.001). In the Swedish cohort, a distinction between foetuses with normal conduction, AVB I, AVB II and III was possible. A significant difference in anti-p200 levels between AVB I and AVB II-III groups compared with foetuses with normal conduction (P < 0.05 and P < 0.01) was observed. Using p200-antibodies as a second step analysis in Ro52-positive pregnancies increased the positive predictive value for foetal cardiac involvement (AVB I, II or III) from 0.39 (0.27-0.51) to 0.53 (0.37-0.68). In conclusion, Ro52 p200-antibodies may occur in women with unaffected children, but levels are significantly higher in mothers of children with congenital heart block and are suggested as a relevant marker in evaluating the risk for foetal AV block.

Preanalytical conditions that affect coagulation testing, including hormonal status and therapy.

Preanalytical conditions, be they due to the individual's physiologic state or to exogenous factors, can affect coagulation factors, in either a transient or a persistent manner, and need to be considered in laboratory testing. These conditions include physical and mental stress, diurnal variation, hormone levels and posture at the time of blood drawing. While testing of these factors has not been exhaustive and some results are conflicting, guidelines for testing conditions can be given.