Prothrombin activation fragment (F1.2) is increased in pregnant patients with antiphospholipid antibodies

Recurrent Miscarriage Syndrome and Infertility Due to Blood Coagulation Protein/Platelet Defects: A Review and Update

Three-hundred fifty-one women were referred for thrombosis and hemostasis evaluation after suffering recurrent miscarriages. All patients were referred by a high-risk obstetrician or reproductive medicine specialist after anatomic, hormonal or chromosomal defects had been ruled out. These patients were assessed over a three year period. The mean patient age at referral was 34 years and the mean number of miscarriages was 2.9 (2-9). All patients underwent a thorough evaluation for thrombophilia and, when indicated, a hemorrhagic disorder. Of the 351 patients, 29 (8%) had no defect. Of the remaining 322 patients, 7 (2%) had a bleeding disorder: 3 with platelet dysfunction, 1 with Factor XIII deficiency, 3 with von Willebrand’s and 3 with Osler-Weber-Rendu. The remainder of the patients had a thrombophilia as follows: 195 (60%) had antiphospholipid syndrome, 64 (20%) had Sticky Platelet Syndrome, 38 (12%) had MTHFR mutation, 23 (7.1%) had PAI-1 polymorphism, 12 (3.7%) had Protein S deficiency, 12 (3.7%) had Factor V Leiden, 3 (1%), had AT deficiency, 3 (1%) had Heparin-Cofactor II deficiency, 3 (1%) had TPA deficiency, and 6 (2%) had Protein C deficiency. There were a total of 364 defects found in the 312 patients harboring thrombophilia; thus, several harbored two and a few harbored three separate defects. All patients with thrombophilia were treated with preconception ASA at 81 mg/day with the immediate post-conception addition of heparin or LMW heparin (Dalteparin). Both ASA and heparin/LMW heparin were used to term. The first 120 patients were treated with unfractionated heparin at 5,000 U every 24 hours, subcutaneously and the last 192 have been treated with Dalteparin at 5,000 U/day subcutaneously. The patients with MTHFR were also treated with folate at 5 mg/day + pyridoxine at 50 mg/day. All patients were carefully monitored with CBC and platelet counts, anti-Xa levels, frequent ultrasounds and physical exams. Only 2 of the thrombophilia patients suffered another miscarriage; all others had a normal term delivery. There were no pregnancy-related thromboses, no delivery complications and no episodes of post-partum thrombosis. The only bleeding consisted of 1-4 cm bruises at injection sites. No episodes of thrombocytopenia (HIT) were noted. In our experience, thrombophilia is a common cause of recurrent miscarriage and all patients with no anatomical, hormonal or chromosomal defect should be evaluated for thrombophilia or a bleeding disorder. The success rate of normal term delivery in these 312 patients was 94% using ASA + heparin or Dalteparin. In addition, side effects of therapy were minimal.

Effects of acute normovolemic hemodilution on perioperative coagulation and fibrinolysis in elderly patients undergoing hepatic carcinectomy

OBJECTIVE

To observe the effects of acute normovolemic hemodilution (ANH) on coagulation function and fibrinolysis in elderly patients undergoing hepatic carcinectomy.

METHODS

Thirty elderly patients (aged 60-70 years) with liver cancer (American Society of Anesthesiologists physical status I-II) scheduled for hepatic carcinectomy from February 2007 to February 2008 were randomly divided into ANH group (n = 15) and control group (n = 15). After tracheal intubation, patients in ANH group and control group were infused with 6% hydroxyethyl starch (HES) (130/0.4), and basic liquid containing 6% HES and routine Ringer's solution, respectively. In all the studied patients, blood samples were drawn at five different time points: before anesthesia induction (T1), 30 minutes after ANH (T2), 1 hour after start of operation (T3), immediately after operation (T4), and 24 hours after operation (T5). Then coagulation function, soluble fibrin monomer complex (SFMC), prothrombin fragment (F1+2), and platelet membrane glycoprotein (activated GPIIb/GPIIIa and P-selectin) were measured.

RESULTS

The perioperative blood loss was not significantly different between the two groups (P > 0.05). The volume of allogeneic blood transfusion in ANH group was significantly smaller than that in control group (350.5 +/- 70.7 mL vs. 457.8 +/- 181.3 mL, P < 0.01). Compared with the data of T1, prothrombin time (PT) and activated partial thromboplastin time in both groups prolonged significantly after T3 (P < 0.05), but still within normal range. There were no significant changes in thrombin time and D-dimer between the two groups and between different time points in each group (all P > 0.05). SFMC and F1 + 2 increased in both groups, but without statistical significance. P-selectin expression on the platelet surface of ANH group was significantly lowered at T2 and T3 compared with the level at T1 (P < 0.05). Compared with control group, P-selectin was significantly lower in ANH group at T2-T5 (all P < 0.05).

CONCLUSIONS

In elderly patients undergoing resection of liver cancer, ANH may not hamper fibrinolysis and coagulation function. It could therefore be safe to largely reduce allogeneic blood transfusion.

Antiphospholipid syndrome in pregnancy

During the past 5 years the author and his colleagues have assessed carefully 351 women referred for evaluation of thrombosis and hemostasis after they had suffered recurrent miscarriages. This article describes the flow protocol the author and associates follow to maximize success and keep the costs of evaluation of recurrent miscarriage syndrome/infertility at a minimum while providing the best chances for defining a cause and thus providing optimal therapy for successful term pregnancy outcome. It presents the outcomes of the author's protocol and those of others in treating women who have antiphospholipid syndrome and who have suffered recurrent miscarriages.

Antiprothrombin antibodies are associated with pregnancy loss in patients with the antiphospholipid syndrome

OBJECTIVE

To document the clinical association between the history of pregnancy loss in patients with the diagnosis of primary or secondary antiphospholipid syndrome (APS) and the presence of different antiprothrombin antibody subtypes [immunoglobulin G (IgG), IgM and IgA] in a cohort of patients with APS.

METHODS

Records of 170 female patients with primary APS, or APS secondary to systemic lupus erythematosus (SLE) or secondary to other autoimmune diseases were studied.

RESULTS

In female APS patients with IgG antiprothrombin antibodies (n = 105) significant associations to pregnancy loss (p < 0.0001), early pregnancy loss (p < 0.0001) and a negative association to thrombocytopenia (p < 0.01) could be identified. In the group of patients with IgG antiprothrombin antibodies and at least one pregnancy (n = 84) a significant association with pregnancy loss (p < 0.005) and especially with early pregnancy loss (p < 0.0001) was demonstrated. No association with other immunoglobulin subtypes of antiprothrombin antibodies could be documented. In the subgroup of patients with primary APS and at least one pregnancy in the history, pregnancy loss (p < 0.005) and early pregnancy loss (p < 0.0001) were found to be highly associated with the presence of IgG antiprothrombin antibodies. IgG antiprothrombin antibodies represent the highest independent risk factor for pregnancy loss with an odds ratio of 4.5. There was no statistically significant association with venous or arterial thrombosis in all IgG antiprothrombin antibody positive patients.

CONCLUSION

The results of this study document the association of IgG antiprothrombin antibodies with pregnancy loss and in particular early pregnancy loss in a large and well-characterized cohort of patients. We would recommend routine testing for antiprothrombin antibodies in young female patients with APS.

Fluctuations in levels of antiphospholipid antibodies and increased coagulation activation markers in normal and heparin-treated antiphospholipid syndrome pregnancies

Antiphospholipid antibodies (aPL) are associated with an increased risk of thrombosis and recurrent miscarriage. We assessed levels of coagulation activation markers and aPL during normal pregnancy and in women with the antiphospholipid syndrome (aPS). Fluctuations in aPL levels were observed in all patients with aPS. No particular pattern of antibody positivity, or fluctuation in aPL level, was associated with poor pregnancy outcome. A significant increase was observed in levels of factor Xlla (FXIIa; P < 0.001), factor VIIa (FVIIa, P < 0.001), thrombin antithrombin complexes (TAT; P < 0.001), prothrombin fragment F1.2 (F1.2; P < 0.001) and D-dimer (DD; P < 0.05) during normal pregnancy. Factor VIIa, TAT, F1.2 and DD increased significantly before 20 weeks gestation, while a statistically significant increase in FXIIa levels was first detected between weeks 20 and 30 of gestation. In pregnant women with aPS, increases in FXIIa were similar to those in normal pregnancy, but increased FVIIa levels were not observed until after 30 weeks gestation. Similar to normal pregnancy, increased levels of TAT and F1.2 were detected in aPS pregnancies before 20 weeks gestation, but increased DD were not observed until after week 20. Surprisingly, women with aPS receiving low molecular weight heparin prophylaxis had significantly higher (P = 0.02) levels of TAT (median 8.6; interquartile range (IQR) 6.5-20.8) between weeks 20 and 30 of gestation compared to the normal pregnant population (median 5.9; IQR 4.7-7.9), thus indicating increased thrombin generation in women with aPS in mid-pregnancy.

Thrombophilia and pregnancy: review of the literature and some original data

The association of thrombophilia with pregnancy complications has received increasing attention. It is now apparent that thrombophilia is responsible for a large number of the serious complications of pregnancy such as venous thrombosis, pulmonary embolism, fetal loss, pregnancy loss, intrauterine fetal demise, and preeclampsia. The inherited thrombophilia abnormalities, factor V Leiden mutation, prothrombin gene mutation 20210A, and antithrombin III, protein C, and protein S deficiency, and the acquired disorders, the anticardiolipin syndrome and lupus inhibitor, are responsible for a large share of the incidences of premature termination of pregnancy and many of the above complications. The normal physiology of pregnancy may be prothrombotic, with evidence for increased markers of activated coagulation and coagulation factors. There is a decrease in protein S and resistance to activated protein C occurs in a significant number of pregnancies in the absence of the factor V Leiden mutation. In the following article, we review some of the major studies that have correlated the thrombophilia and other acquired disorders that adversely impact pregnancies.

Which antiphospholipid antibody tests are most useful?

Despite an active international effort to improve diagnosis and treatment of the antiphospholipid syndrome (Hughes syndrome), there remain problems of lack of standardization and lack of prospective and multivariate epidemiologic analysis which restrict the diagnostic and predictive ability of commercially available tests. Nevertheless, current published series provide some data from which strategic approaches can be used to maximize the efficiency and usefulness of available tests. For further updates on new research and developments of interest to physicians and patients with this syndrome, the following web sites may prove helpful: www.slrapls.org, www.hematology.org, www.acforum.org, www.americanheart.org, www.rarediseases.org, www.aarda.org, and www.lupus.org.

Antiphospholipid syndrome and recurrent miscarriages

Sixty percent of recurrent spontaneous abortions are unexplained. Antiphospholipid syndrome is a multisystem disease with the predominant features of venous and arterial thrombosis, recurrent pregnancy loss, foetal death and the presence of antiphospholipid antibodies. Many epidemiological studies focus on antiphospholipid autoantibodies syndrome (APS) as a cause of recurrent spontaneous abortion (RSA). It is found that 7-25% of RSA would have APS as the main risk factor. 'Association not being synonymous with cause', the proportion of abortions due to the APS is difficult to estimate for several reasons: definition of recurrent abortion is variable, the assays for antiphospholipid antibodies are not well standardised, inclusion of patients in the study group according to the antibodies titre is author dependent. Recent studies suggest association of antiphospholipid antibodies syndrome not only with recurrent abortions but also with infertility. New mechanisms are described by which antiphospholipid antibodies could cause placental thrombosis and infarction, acting directly on the surface anticoagulant expressed on trophoblastic cells. Only lupus anticoagulant (LA) and anticardiolipin antibodies (aCL) assays are sufficiently standardised to be usable in routine. Testing for other antiphospholipid antibodies (aPLs) should remain investigational. Several treatments have been proposed: low doses of aspirin, low or immunosuppressive doses of corticosteroids, and preventive or effective dose of heparin, intravenous immunoglobulin.

Coagulation activation markers do not correlate with the clinical risk of thrombosis in pregnant women

OBJECTIVE

Because coagulation activation markers have been shown to indicate an increased risk of thrombosis, we tested whether thrombin-antithrombin III complexes and D-dimers correlated with the risk assessment in pregnant women on the basis of clinical data.

STUDY DESIGN

We divided a group of 261 pregnant women (305 pregnancies) into low- and high-risk groups according to the personal and family histories of thrombosis and the presence of a hereditary or an acquired thrombophilia. Women with a thrombotic event in the current pregnancy formed a separate group. All pregnancies with or without heparin therapy were closely monitored with thrombin-antithrombin III and D-dimer values for the entire course of the pregnancy. Retrospectively, the data were then correlated with the different groups and subgroups.

RESULTS

The course of the mean thrombin-antithrombin III values of all 305 pregnancies was close to or slightly above the upper cutoff line, whereas the D-dimer values were well within the normal range. Independent of heparin, there was no difference in the course of the thrombin-antithrombin III and D-dimer values between the low- and high-risk groups. Only women with ongoing thrombosis during pregnancy had significantly higher thrombin-antithrombin III and D-dimer values with or without heparin therapy. Among those individuals with elevated thrombin-antithrombin III or D-dimer values, there were no specific, recognizable patients who had elevated markers more often than others.

CONCLUSIONS

Thrombin-antithrombin III and D-dimer values do not correlate with a risk stratification assessed by clinical criteria. There are many women at low clinical risk who have elevated markers, and there are many women at very high clinical risk who have normal markers. Thus thromboprophylaxis would often be used inadequately if the indication were based on coagulation markers.

Recurrent miscarriage syndrome and infertility caused by blood coagulation protein or platelet defects

Recurrent miscarriage syndrome and infertility are common problems in the United States. Recurrent miscarriage affects more than 500,000 women annually. If properly screened through a cost-effective protocol, the cause will be found in almost all women. The most common singular defect in women with RMS is a hemostasis defect, and if a thorough APLS evaluation is performed, the most common of these is found to be APLS. Other hereditary and acquired procoagulant defects are also commonly found, if looked for. It is important to evaluate women with RMS appropriately, because if a cause for the RMS is found, most women will achieve normal-term delivery. Hemorrhagic defects are rare hemostasis causes of RMS, but these defects also are treatable in many instances and should be considered in appropriate women. Treatment of the common procoagulant defects consists of preconception low-dose ASA at 81 mg/day followed by immediate postconception low-dose unfractionated porcine heparin. LMWH may be a suitable alternative.

Recurrent miscarriage syndrome due to blood coagulation protein/platelet defects: prevalence, treatment and outcome results. DRW Metroplex Recurrent Miscarriage Syndrome Cooperative Group

Although first-time miscarriages are usually caused by chromosomal defects, about 55% of recurrent miscarriages are caused by procoagulant defects that induce thrombosis and infarction of placental vessels. Of recurrent miscarriages, about 7% are caused by chromosome defects, 15% to hormonal defects, and 10% to 15% to anatomical defects. Recurrent miscarriage involves more than 500,000 women in the United States each year. During the past 4 years, 179 patients, prescreened for chromosomal, hormonal, and anatomical defects, and found to harbor none, underwent hemostasis defect evaluation. A total of 160 of these have been analyzed. A hemostasis defect was found in 150 of 160 women (n = 94% of screened women). The mean age was 33 years; the mean number of miscarriages before referral was three. All women with a procoagulant defect (149) were treated with preconception ASA at 81 mg/d, and unfractionated porcine heparin at 5000 U every 12 hours was added immediately postconception; both agents were used to term delivery. Only two of 149 patients failed therapy. The defects found were as follows: antiphospholipid syndrome, 67%; sticky platelet syndrome, 21%; tissue plasminogen activator (TPA) deficiency, 9%; factor V Leiden, 7%; high PAI-1, 6%; protein S, 5%; high LP(a), 3%; AT, 2%; protein C, 1%. Thirty-eight patients had more than one defect. In the group with antiphospholipid syndrome, 24% only had a subgroup antibody (antiphosphatidyl-serine, -inositol, -ethanolamine, -choline, -glycerol) or antiphosphatidic acid antibody, in the absence of anticardiolipin antibody or lupus anticoagulant. This finding is similar to that recently reported in early age ischemic stroke patients (<50 years old). In summary, about 55% of patients with recurrent miscarriage harbor a procoagulant defect to account for placental vascular occlusion. More than 98% will have a normal term delivery with preconception aspirin (ASA) and addition of postconception heparin to term. Patients should be screened by an obstetrician or by reproductive specialists for hormonal and anatomic defects before initiating a procoagulant evaluation; if such prescreening is done, the yield of a defect is high and appropriate therapy leads to an excellent outcome.

Antiphospholipid antibody syndrome: new insights on thrombogenic mechanisms

The antiphospholipid antibody syndrome is a thrombophilic condition manifested by vascular thrombosis or recurrent pregnancy loss together with the presence of antibodies against anionic phospholipid protein complexes. These antibodies are detected by their reactivity to the anionic phospholipids (or protein phospholipid complexes) in solid-phase immunoassays or by their property of inhibiting phospholipid-dependent coagulation reactions (the "lupus anticoagulant" effect). The pathophysiologic mechanisms of this syndrome have remained obscure because of the apparent multiplicity of antigenic determinants recognized by the antibodies and also because of the many effects which have been described for them. This article reviews current concepts of the antiphospholipid disease process and evidence for the hypothesis that thrombosis in this syndrome is a result of the displacement of annexin-V, an anionic phospholipid-binding protein with potent anticoagulant activity, from phospholipid surfaces. The authors propose that under physiologic conditions, annexin-V plays a thromboregulatory role at the vascular-blood interface by shielding anionic phospholipids from complexation with coagulation proteins in circulating blood. Thrombosis in the antiphospholipid syndrome is due to disruption of the annexin shield by antiphospholipid (and cofactor) antibodies which results in the increased exposure of thrombogenic phospholipids. Accumulated data are consistent with the hypothesis that the disruption of annexin-V binding to anionic phospholipid surfaces plays an important thrombogenic role in the antiphospholipid syndrome.