Hémostase et prééclampsie

Interrelationship Between Markers of Oxidative Stress, Inflammation and Hematological Parameters Among Preeclamptic Nigerian Women

BACKGROUND Preeclampsia is a multifaceted pregnancy-related disorder affecting women and fetuses. A link between preeclampsia, oxidative stress, and inflammation has been suggested. This study evaluated the interrelationship between biomarkers of oxidative stress, inflammation, and hematological parameters among preeclamptic Nigerian women. MATERIAL AND METHODS A cross-sectional study was conducted among 49 preeclamptic and 50 normotensive healthy pregnant women. Blood samples were obtained after 20-week gestation in all participants. Levels of superoxide dismutase (SOD), catalase, glutathione (GSH), malonaldehyde (MDA), total protein, high-sensitivity C-reactive protein (hs-CRP), and cardiac-specific troponin I (cTnI) were determined by spectrophotometric and ELISA techniques. FBC, prothrombin time, and activated partial thromboplastin time were determined using an auto-analyzer, Quick's one-stage, and Proctor's and Rappaport's modification methods, respectively. RESULTS The mean SOD (0.051±0.050 vs. 0.073±0.047, p 0.029), catalase (2.62±1.93 vs. 8.48±4.40, p<0.001), GSH (49.05±17.57 vs. 187.10±56.07 p<0.001), platelet (127.63±89.75 vs. 267.16±212.82, p<0.001 were lower in preeclampsia. MDA (7.16±5.00 vs. 2.91±2.66, p<0.001), cTnI (0.46±0.31 vs. 0.13±0.14 p<0.001), PT (19.36±4.06 vs. 13.45±1.97 p<0.001), APTT (45.53±2.92 vs. 37.49±4.99; p<0.001) were higher in preeclampsia. Negative associations between SOD and MDA (r -0.527 p<0.001), CAT and MDA (r -0.469, p 0.001) and positive associations between catalase and hs-CRP (r 0.844, p 0.029), RBC and HB (r 0.442, p 0.001), platelet, and SOD (r 0.353, p 0.013) were observed among preeclamptic volunteers. CONCLUSIONS Preeclampsia is associated with oxidative stress, derangement of hematological and coagulation homeostasis, as well as deleterious effects on the cardiovascular system.

Fibrinolytic proteins of normal pregnancy and pre-eclamptic patients in North West Nigeria

BACKGROUND

The hypercoagulability of pregnancy is exaggerated in pre-eclamptic state because of endothelial activation with resultant production of some endothelial derived proteins that are said to be inhibitors of fibrinolysis. This study compares these proteins like tPA, PAI-1 and D-dimers in normal pregnant women and the pre-eclamptic women.

METHODOLOGY

This was a comparative cross-sectional study. Eighty-five pre-eclamptic women were recruited as subjects and eighty five age, trimester and parity matched normotensive pregnant women as controls. Levels of PT, aPTT, tPA, PAI-1, D-dimer protein were determined in blood samples of subjects and controls. Urinalysis was performed with dipstick method on their urine samples. Data generated was analysed using the IBM®SPSS 20.0 (2011) soft ware packages and the level of significance was a p-value <0.05.

RESULTS

The mean age of the respondents was 29.9±5.2 years. The median(25th-75th percentile) values of D-dimer, tPA, and PAI-1 of subjects were 730 (305.000-1560.000ng/ml), 0.11 (0.065-0,300ng/ml) and 3.65 (2.970-4,400ng/ml) respectively which were significantly higher than the corresponding values in the controls of 520 (24.000-1030.000ng/ml), 0.05 (0.040-0.090ng/ml and 2.650 (2.125-3.400ng/ml) respectively, p<0.05 each.

CONCLUSION

The abnormal levels of PAI-1, D-dimer and tPA imply that they contribute to the exaggerated hypercoagulabilty state in pre-eclampsia thus, measuring their levels can help in the management of the condition.

Comparison of Two Diagnostic Scores of Disseminated Intravascular Coagulation in Pregnant Women Admitted to the ICU

Objective

To compare the validity of two previously published diagnostic scores of disseminated intravascular coagulation (DIC) in pregnant women admitted to ICU for an acute thrombotic or hemorrhagic complication of delivery and postpartum.

Methods

This was a population based retrospective study of 154 patients admitted to ICU for severe delivery and postpartum complications in a University Hospital. A recently published score (adapted to physiological changes of pregnancy and based on three components: platelet count, prothrombin time difference and fibrinogen) was compared to the International Society for Thrombosis and Hemostasis (ISTH) score (based on four components: platelet count, fibrinogen, prothrombin time, and fibrin related marker). Both scores were calculated at delivery, ICU admission (day 0), day 1 and day 2 during the postpartum ICU stay. The validity of both scores was assessed by comparison with the consensual and blinded analysis of two experts. The sensitivity, specificity, and area under the curve (AUC) of each score were calculated at each time and overall by generalized linear mixed model. The agreement between the two scores was evaluated by the Kappa coefficient.

Results

The new score had a sensitivity of 0.78, a specificity of 0.97 (p <0.01) and a global AUC of 96% while the ISTH score had a sensitivity of 0.31, a specificity of 0.99 and an AUC of 94% (p <0.01). The Kappa coefficient of correlation between both scores was 0.35. The lower sensitivity of the ISTH score was mainly explained by the lack of fibrinogen and fibrin-related peptides thresholds adapted to the physiological changes of coagulation induced by pregnancy.

Conclusion

The new DIC score seem highly discriminant in the subset of patients admitted to the ICU after delivery for an acute specific complication. The ISTH score is not recommended in pregnant women because of its poor sensitivity.

A Dormant Microbial Component in the Development of Preeclampsia

Preeclampsia (PE) is a complex, multisystem disorder that remains a leading cause of morbidity and mortality in pregnancy. Four main classes of dysregulation accompany PE and are widely considered to contribute to its severity. These are abnormal trophoblast invasion of the placenta, anti-angiogenic responses, oxidative stress, and inflammation. What is lacking, however, is an explanation of how these themselves are caused. We here develop the unifying idea, and the considerable evidence for it, that the originating cause of PE (and of the four classes of dysregulation) is, in fact, microbial infection, that most such microbes are dormant and hence resist detection by conventional (replication-dependent) microbiology, and that by occasional resuscitation and growth it is they that are responsible for all the observable sequelae, including the continuing, chronic inflammation. In particular, bacterial products such as lipopolysaccharide (LPS), also known as endotoxin, are well known as highly inflammagenic and stimulate an innate (and possibly trained) immune response that exacerbates the inflammation further. The known need of microbes for free iron can explain the iron dysregulation that accompanies PE. We describe the main routes of infection (gut, oral, and urinary tract infection) and the regularly observed presence of microbes in placental and other tissues in PE. Every known proteomic biomarker of "preeclampsia" that we assessed has, in fact, also been shown to be raised in response to infection. An infectious component to PE fulfills the Bradford Hill criteria for ascribing a disease to an environmental cause and suggests a number of treatments, some of which have, in fact, been shown to be successful. PE was classically referred to as endotoxemia or toxemia of pregnancy, and it is ironic that it seems that LPS and other microbial endotoxins really are involved. Overall, the recognition of an infectious component in the etiology of PE mirrors that for ulcers and other diseases that were previously considered to lack one.

The simultaneous occurrence of both hypercoagulability and hypofibrinolysis in blood and serum during systemic inflammation, and the roles of iron and fibrin(ogen)

Although the two phenomena are usually studied separately, we summarise a considerable body of literature to the effect that a great many diseases involve (or are accompanied by) both an increased tendency for blood to clot (hypercoagulability) and the resistance of the clots so formed (hypofibrinolysis) to the typical, 'healthy' or physiological lysis. We concentrate here on the terminal stages of fibrin formation from fibrinogen, as catalysed by thrombin. Hypercoagulability goes hand in hand with inflammation, and is strongly influenced by the fibrinogen concentration (and vice versa); this can be mediated via interleukin-6. Poorly liganded iron is a significant feature of inflammatory diseases, and hypofibrinolysis may change as a result of changes in the structure and morphology of the clot, which may be mimicked in vitro, and may be caused in vivo, by the presence of unliganded iron interacting with fibrin(ogen) during clot formation. Many of these phenomena are probably caused by electrostatic changes in the iron-fibrinogen system, though hydroxyl radical (OH˙) formation can also contribute under both acute and (more especially) chronic conditions. Many substances are known to affect the nature of fibrin polymerised from fibrinogen, such that this might be seen as a kind of bellwether for human or plasma health. Overall, our analysis demonstrates the commonalities underpinning a variety of pathologies as seen in both hypercoagulability and hypofibrinolysis, and offers opportunities for both diagnostics and therapies.

Anticoagulant effect of Huisheng Oral Solution in a rat model of thrombosis

OBJECTIVE

To investigate whether Huisheng Oral Solution has an anticoagulant effect in a rat model of thrombosis.

MATERIALS AND METHODS

A total of 40 male SD rats were equally and randomly divided into four groups: blank group, model group, and two treatment groups (A and B). Rats were subcutaneously injected with carrageenan to induce thrombosis. Rats in the treatment group A were intragastrically administered with Huisheng Oral Solution at a dose of 2 ml/100 g body weight (once per 8 hours), 72 hours after carrageenan injection, while those in the treatment group B were administered with Huisheng Oral Solution both 72 hours before and after induction of thrombosis. Blood samples were collected 24, 48, and 72 hours after carrageenan injection for measurements of prothrombin time (PT), activated partial thromboplastin time (APTT), international normalized ratio (INR), fibrinogen (FIB), prothrombin activity (PTA), platelets (PLT), fibrin degradation products (FDPs), and D-dimer. Lung, liver, and mesentery samples were taken 72 hours after carrageenan injection for histopathological analysis. The numbers of microthrombi in sections of different tissue samples were counted under a microscope. Blood parameters among each group were compared using the Welch test, the Kruskal-Wallis test, or the SNK test after testing for normality, while the number of microthrombi was compared using the Bonferroni test.

RESULTS

Compared to those in the model group, PT, APTT, and INR were significantly prolonged or increased while FIB was significantly reduced at the majority of time points in the two treatment groups (P < 0.05 for all). The levels of FDPs and D-dimer and PLT counts at the majority of time points were significantly lower (P < 0.05 for all), and the numbers of microthrombi in lung, liver, and mesentery samples were significantly decreased (P < 0.05 for all) in the two treatment groups. The above parameters at the majority of time points showed no significant differences between the two treatment groups.

CONCLUSIONS

Huisheng Oral Solution can significantly improve coagulation parameters, fibrinolysis parameters, and PLT count, and reduce blood hypercoagulability and microthrombosis, suggesting that Huisheng Oral Solution has an anticoagulant effect in a rat model of thrombosis.

[Severe pre-eclampsia. An evidence-based practice proposal]

OBJECTIVES

There are several treatment proposals for the obstetric patient with pre-eclampsia, but there is limited evidence on the adequacy of standard treatment. International healthcare organisations recommend that hospitals or anaesthesia departments have written guidelines, protocols or recommendations for dealing with common or severe situations. We propose evidence-based recommendations for the treatment of pre-eclampsia.

MATERIAL AND METHODS

A literature review was performed using several sources, bibliography databases, recommendations made by specialist societies, and reviews. Four anaesthesiologists reviewed the references selected, in order to design clinical questions (these were obtained from recent pre-eclampsia review articles). Consensus of at least 3 out of 4 experts was required. The Oxford criteria for evidence were chosen to classify the scientific articles, and the Jadad score was applied to the final articles selected.

RESULTS

A total of 50 clinical questions were designed and answered. These were classified into: general questions, influence of the type of delivery, pre-anaesthesia evaluation, peripartum treatment (including analgesia and anaesthesia), eclampsia, post-delivery period, and intensive care and transport. Most of the responses showed low scientific evidence.

CONCLUSIONS

Evidence-based recommendations for severe pre-eclampsia treatment were provided with special emphasis on the anaesthesiologist point of view.