Clinical and economic burden of immune tolerance induction in entire patients with hemophilia A: Insights from a real-world Korean setting

INTRODUCTION

The most notable challenge facing hemophilia A treatment is the development of inhibitors against factor VIII, resulting in increased clinical and socioeconomic burdens due to the need for expensive bypassing agents (BPAs). Although immune tolerance induction (ITI) is currently the primary approach for inhibiting and reducing the inhibitors, the lengthy duration of ITI necessitates the continued use of BPA to manage bleeding episodes. In this study, we aimed to obtain real-world evidence on the clinical and economic aspects and associated burdens experienced by patients with hemophilia A with inhibitors undergoing ITI in Korea.

METHODS

Claims data from January 1, 2007, to December 31, 2020, were used in this study. The study cohort comprised patients with hemophilia A undergoing ITI, who were categorized into three groups: successful, failed, or continuation of ITI. We evaluated clinical and economic burdens, including monthly healthcare visits, medication costs, and total medical expenses.

RESULTS

The study involved 33 cases of ITI across 32 patients. Excluding seven continuation cases where success could not be determined at the observation point, the estimated success rate of ITI was 80.8 %. The median duration of ITI for all patients was 25.7 months. While no significant disparities were noted in the ITI duration between successful and unsuccessful cases (24.51 vs. 25.66 months), substantial discrepancies were observed in the duration of BPA usage (11.10 vs. 25.66 months) and the number of prescribed BPAs (1.79 vs. 2.97).

CONCLUSION

Successful ITI reduced both clinical and economic burdens, resulting in decreased monthly medication expenses and overall medical costs.

The role of coagulation factors VIII, IX and XI in the prediction and mediation of recurrent thrombotic events in children with non-central venous catheter deep vein thrombosis

BACKGROUND

The role of elevated coagulation factors VIII (FVIII), FIX, FXI for the prediction of recurrent thrombotic events in children after an index non-central venous catheter (non-CVC) related deep vein thrombosis (DVT) remains unclear.

OBJECTIVE

This study investigates the predictive role of FVIII, FIX, and FXI for recurrent thrombosis in children with index non-CVC DVTs, and the mediation effect of FVIII on chronic inflammation and recurrent thrombosis.

METHODS

Children aged 0-18 years diagnosed with an index non-CVC related DVT (1993-2020) were included in this single-center retrospective cohort study. Plasma levels of FVIII, FIX, FXI were measured cross-sectionally ≥30 days after the acute DVT. The association between the continuous variables FVIII, FIX, FXI and thrombosis recurrence was investigated using uni- and multivariable logistic regression, adjusting for age, sex, and chronic inflammation. Mediation analysis assessed the role of FVIII as a mediator between chronic inflammation and recurrent thrombosis. Ethics approval was obtained.

RESULTS

A total of 139 children with an index non-CVC related DVT were included. Thirty-eight (27 %) had a recurrent thrombosis at a median of 237 days (P25-P75 65-657 days) after the index DVT. In uni- and multivariable-analysis, FVIII, FIX or FXI did not predict thrombosis recurrence; However, chronic inflammation was an independent predictor. There was no evidence that FVIII mediated the effect of chronic inflammation on thrombosis recurrence.

CONCLUSION

We found no evidence that elevated FVIII, FIX or FXI predicted thrombosis recurrence, or evidence of a mediating role of FVIII. Underlying chronic inflammation predicted venous recurrent thrombotic events in this cohort.

SARS-CoV-2 S protein activates NLRP3 inflammasome and deregulates coagulation factors in endothelial and immune cells

BACKGROUND

Hyperinflammation, hypercoagulation and endothelial injury are major findings in acute and post-COVID-19. The SARS-CoV-2 S protein has been detected as an isolated element in human tissues reservoirs and is the main product of mRNA COVID-19 vaccines. We investigated whether the S protein alone triggers pro-inflammatory and pro-coagulant responses in primary cultures of two cell types deeply affected by SARS-CoV-2, such are monocytes and endothelial cells.

METHODS

In human umbilical vein endothelial cells (HUVEC) and monocytes, the components of NF-κB and the NLRP3 inflammasome system, as well as coagulation regulators, were assessed by qRT-PCR, Western blot, flow cytometry, or indirect immunofluorescence.

RESULTS

S protein activated NF-κB, promoted pro-inflammatory cytokines release, and triggered the priming and activation of the NLRP3 inflammasome system resulting in mature IL-1β formation in both cell types. This was paralleled by enhanced production of coagulation factors such as von Willebrand factor (vWF), factor VIII or tissue factor, that was mediated, at least in part, by IL-1β. Additionally, S protein failed to enhance ADAMTS-13 levels to counteract the pro-coagulant activity of vWF multimers. Monocytes and HUVEC barely expressed angiotensin-converting enzyme-2. Pharmacological approaches and gene silencing showed that TLR4 receptors mediated the effects of S protein in monocytes, but not in HUVEC.

CONCLUSION

S protein behaves both as a pro-inflammatory and pro-coagulant stimulus in human monocytes and endothelial cells. Interfering with the receptors or signaling pathways evoked by the S protein may help preventing immune and vascular complications driven by such an isolated viral element. Video Abstract.

Prothrombin complex concentrate (PCC) for treatment of trauma-induced coagulopathy: systematic review and meta-analyses

BACKGROUND

Trauma-induced coagulopathy (TIC) is common in trauma patients with major hemorrhage. Prothrombin complex concentrate (PCC) is used as a potential treatment for the correction of TIC, but the efficacy, timing, and evidence to support its use in injured patients with hemorrhage are unclear.

METHODS

A systematic search of published studies was performed on MEDLINE and EMBASE databases using standardized search equations. Ongoing studies were identified using clinicaltrials.gov. Studies investigating the use of PCC to treat TIC (on its own or in combination with other treatments) in adult major trauma patients were included. Studies involving pediatric patients, studies of only traumatic brain injury (TBI), and studies involving only anticoagulated patients were excluded. Primary outcomes were in-hospital mortality and venous thromboembolism (VTE). Pooled effects of PCC use were reported using random-effects model meta-analyses. Risk of bias was assessed for each study, and we used the Grading of Recommendations Assessment, Development, and Evaluation to assess the quality of evidence.

RESULTS

After removing duplicates, 1745 reports were screened and nine observational studies and one randomized controlled trial (RCT) were included, with a total of 1150 patients receiving PCC. Most studies used 4-factor-PCC with a dose of 20-30U/Kg. Among observational studies, co-interventions included whole blood (n = 1), fibrinogen concentrate (n = 2), or fresh frozen plasma (n = 4). Outcomes were inconsistently reported across studies with wide variation in both measurements and time points. The eight observational studies included reported mortality with a pooled odds ratio of 0.97 [95% CI 0.56-1.69], and five reported deep venous thrombosis (DVT) with a pooled OR of 0.83 [95% CI 0.44-1.57]. When pooling the observational studies and the RCT, the OR for mortality and DVT was 0.94 [95% CI 0.60-1.45] and 1.00 [95% CI 0.64-1.55] respectively.

CONCLUSIONS

Among published studies of TIC, PCCs did not significantly reduce mortality, nor did they increase the risk of VTE. However, the potential thrombotic risk remains a concern that should be addressed in future studies. Several RCTs are currently ongoing to further explore the efficacy and safety of PCC.

Use of four-factor prothrombin complex concentrate (4F-PCC) for management of bleeding not associated with therapeutic anticoagulant use

INTRODUCTION

Four-factor prothrombin complex concentrate (4F-PCC) may be an option for patients with bleeding unrelated to therapeutic anticoagulation to help with bleeding cessation and reduce blood component requirements.

MATERIALS AND METHODS

Retrospective, observational study of adult patients who received 4F-PCC for bleeding not associated with therapeutic anticoagulation between June 2019 and July 2021. Primary outcome was to describe off-label 4F-PCC use in patients not on therapeutic anticoagulation for bleeding management in surgical and non-surgical patients. Additional outcomes evaluated were blood product use, chest tube and drainage output, and coagulation studies before and after 4F-PCC administration as well as other hemostatic agent use and thromboembolic events.

RESULTS

Seventy-six patients were included; median age 64 years (IQR 50-69), 66% of bleeding events were associated with surgery, and the majority of 4F-PCC doses ordered by cardiac surgery (68.4%). A total of 110 4F-PCC doses were administered; median 1 dose/patient (IQR 1-2), median total dose 1000 units (IQR 500-1484). Other hemostatic agents commonly administered were protamine (59%), desmopressin (43%), and tranexamic acid (42%). Packed red blood cells, fresh frozen plasma, platelet, and cell saver blood administration and prothrombin time (PT), international normalized ratio (INR), and partial thromboplastin time (aPTT) were significantly reduced following 4F-PCC administration. Eight patients (11%) experienced thromboembolic complications.

CONCLUSION

Relatively low doses of 4F-PCC (median total dose 1000 units) were associated with decreased blood component requirements and improved PT, INR, and aPTT values in patients with bleeding unrelated to therapeutic anticoagulation. Other hemostatic agent use was common and thromboembolic complications occurred.

Comparison of the International Normalized Ratio Between a Point-of-Care Test and a Conventional Laboratory Test: the Latter Performs Better in Assessing Warfarin-induced Changes in Coagulation Factors

Background

Point-of-care testing (POCT) coagulometers are increasingly used for monitoring warfarin therapy. However, in high international normalized ratio (INR) ranges, significant discrepancy in the INR between POCT and conventional laboratory tests occurs. We compared the INR of POCT (CoaguChek XS Plus; Roche Diagnostics, Mannheim, Germany) with that of a conventional laboratory test (ACL TOP 750; Instrumentation Laboratory SpA, Milan, Italy) and explored possible reasons for discrepancy.

Methods

Paired POCT and conventional laboratory test INRs were analyzed in 400 samples from 126 patients undergoing warfarin therapy after cardiac surgery. Coagulation factor and thrombin generation tests were compared using the Mann-Whitney U test. Correlations between coagulation factors and INRs were determined using Pearson correlation coefficients.

Results

The mean difference in the INR between the tests increased at high INR ranges. Endogenous thrombin potential levels were decreased at INR <2.0 for CoaguChek XS Plus and 2.0< INR <3.0 for ACL TOP 750 compared with those at INR <2.0 for both tests, indicating a better performance of ACL TOP 750 in assessing thrombin changes. The correlation coefficients of coagulation factors were stronger for ACL TOP 750 INR than for CoaguChek XS Plus INR. Vitamin K-dependent coagulation factors were found to contribute to the INR discrepancy.

Conclusions

Decreases in vitamin K-dependent coagulation and anticoagulation factors can explain the significant discrepancy between the two tests in high INR ranges. Since conventional laboratory test INR values are more reliable than POCT INR values, a confirmatory conventional laboratory test is required for high INR ranges.

Effects of wasp venom on venous thrombosis in rats

OBJECTIVES

This study aimed to investigate the potential effects of wasp venom (WV) from Vespa magnifica on antithrombosis in rats with inferior vena cava (IVC) thrombosis.

MATERIALS AND METHODS

The thrombosis rat model was established by improving the IVC stenosis, in which rats were subjected to IVC ligation for 75 min. Rats were administered argatroban (IP) or WV (s.c.) for 4 hr after IVC thrombosis. The weight, inhibition rate, and pathological morphology of the thrombosis induced by IVC ligation and the variation in four coagulation parameters, coagulation factors, and CD61+CD62P+ were simultaneously determined in IVC rats.

RESULTS

The thrombus formed as a result of IVC ligation was stable. Compared with the control group, the weight of the thrombus was significantly reduced in the argatroban group. Thrombus weight was reduced by treatment with 0.6, 0.2, and 0.05 mg/kg WV, with inhibition rates of 52.19%, 35.32%, and 28.98%, respectively. Inflammatory cells adhered to and infiltrated the vessel wall in the IVC group more than in the sham group. However, the pathological morphology and CD61+CD62P+ of the WV treatment groups tended to be normal.

CONCLUSION

We improved the model of IVC thrombosis to be suitable for evaluation of antithrombotic drugs. Our findings demonstrated that WV could inhibit IVC thrombosis associated with reducing coagulation factors V and CD61+CD62p expression in rats.

The mediating role of coagulation function on the association of prenatal exposure to aflatoxin B1 and postpartum hemorrhage in Guangxi, China

Pregnant women are vulnerable to certain environmental agents, one of which is aflatoxin. As one of the most popular aflatoxins, Aflatoxin B1 (AFB1) has recently garnered increased attention concerning its potential association between exposure and adverse pregnancy outcomes. The aims of the study were to examine the associations between prenatal exposure to AFB1 and postpartum hemorrhage (PPH), and whether coagulation function has a mediating effect on their relationship. A total of 379 mother-infant pairs were included in the present study. Prenatal serum AFB1 albumin (AFB1-Alb) adduct levels in peripheral venous blood were detected by using an ELISA kit. Multiple linear and logistics regression models were applied to analyze the relationship between AFB1-Alb levels and PPH. We found mothers with high levels of AFB1-Alb adduct levels had significantly increased postpartum blood loss (partial regression coefficient (β) = 50.71, 95% confidence interval (CI) 3.48, 97.95). Mothers with high levels of AFB1-Alb adduct levels also had significantly increased risk of PPH (odds ratio (OR) = 4.81, 95% CI 1.01, 22.98). Moreover, concentrations of AFB1-Alb were positively associated with activated partial thromboplastin time (APTT) while negatively associated with fibrinogen (FIB). One-unit increase in APTT was correlated with a 6.62-ml (95% CI 3.04, 10.20) increase in postpartum blood loss. Mediation analysis suggested that the maternal blood APTT levels had a positive mediating effect in the association between AFB1-Alb adduct levels and postpartum blood loss (β = 0.32, 95% CI 0.04, 0.68). These results indicated that prenatal exposure to AFB1 was associated with increased postpartum blood loss, possibly by interfering with maternal APTT levels.

Incidence of thrombotic complications related to weight-based dosing of activated prothrombin complex concentrate (aPCC) for reversal of apixaban and rivaroxaban in obese patients

Factor eight inhibitor bypassing activity (aPCC) is recommended as a non-specific reversal agent for direct oral anticoagulants (DOACs) according to the 2017 American College of Cardiology (ACC) guidelines for reversal of anticoagulation. Factor eight inhibitor bypassing activity carries a black box warning for thrombotic events such as stroke, pulmonary embolism, deep vein thrombosis, and myocardial infarction, particularly at high doses. This was a retrospective, single-center, cohort investigation that included patients who received a weight-based dose of aPCC for reversal of apixaban and rivaroxaban between January 1, 2015, and December 31, 2020. Patients were grouped by BMI as obese (BMI ≥ 30 kg/m²) or non-obese (BMI < 30 kg/m²) for analysis. The primary outcome of this investigation was the occurrence of thrombotic complications [venous thromboembolism (VTE), myocardial infarction, stroke] documented in the medical record at any point during hospitalization after administration of aPCC. Secondary outcomes included bleeding complications, in-hospital mortality, ICU and hospital length of stay. Patients in the obese group were younger [76.4 years (SD +/- 11.3 years) vs. 69.6 years (SD +/- 12.4 years); p < 0.0001] and a higher proportion had a diagnosis of diabetes mellitus prior to admission [37 (19.2%) vs. 35 (36.8%); p = 0.0011]. There was no difference in the primary outcome of thrombotic events between non-obese and obese patients [12 (6.2%) vs. 5 (5.3%); p = 0.75], or for any of the secondary outcomes of bleeding, in-hospital mortality or length of stay. This investigation did not reveal a difference in rates of thrombosis or bleeding events between obese and non-obese patients who received aPCC for reversal of apixaban and rivaroxaban.

[Pathophysiology of bleeding]

Bleeding is associated with an increased morbidity and mortality. Anatomic and hemostatic causes play a central role in the pathophysiology of bleeding, with anatomic causes being by far more common. While trauma and invasive procedures are the leading causes of bleeding in surgical disciplines, gastrointestinal bleeding is the major cause of bleeding in internal medicine. Major bleedings lead to secondary homeostatic changes, which in turn not only contribute to further bleeding, but also to the pathogenesis of organ dysfunction. Acquired coagulopathies due to antithrombotic treatment or an underlying disease also contribute to the extent and the dynamics of bleeding, while hereditary bleeding disorders are seldom. The balance between the physiological pro- and anticoagulant pathway plays a significant role in the pathophysiology of bleeding and coagulation. Therefore, the pathophysiology of bleeding cannot be described by means of easily available laboratory coagulation workup. The aim of coagulation correction during the management of life-threatening bleeding is not to normalize coagulation, but rather to stop bleeding. Besides a careful clinical evaluation of the course of bleeding coupled with basic understanding of the physiology of coagulation, targeted laboratory coagulation workup can contribute to a rational coagulation treatment concept.

Clinical utilization of four-factor prothrombin complex concentrate: a retrospective single center study

OBJECTIVE

Four-factor prothrombin complex concentrate (4F-PCC) was approved by the US Food and Drug Administration in 2013 for management of severely bleeding patients on warfarin therapy. We describe use of 4F-PCC at a large, suburban academic center.

METHODS

We retrospectively reviewed all patients receiving 4F-PCC from its introduction through 2016 at a large level 1 trauma center. Clinical and demographic data were obtained, including indications for anticoagulation and antiplatelet agents, comorbidities, concomitant medications, etiology and site of bleeding, as well as disposition, length of stay, mortality, and thrombotic events.

RESULTS

One hundred eighty-four patients received 4F-PCC. Mean age was 72 years; 40.8% were female. Indications for 4F-PCC administration included: active bleeding (74%), reversal prior to a procedure (14%), and elevated international normalized ratio (12%). Warfarin was the most common concomitant medication (71.1%). Most patients were receiving anticoagulation for atrial fibrillation (63%). Concomitant treatments for bleeding included vitamin K (58.2%), packed red blood cells (50%), fresh frozen plasma (38%), and platelets (26.1%), amongst others. Median length of hospital stay was 8.4 days. Nine patients (4.9%) developed thrombosis within 90 days of 4F-PCC. Mortality was 24.5%, with notably higher rates amongst those who received 4F-PCC for off-label indications (19.1% on-label mortality vs. 37.7% off-label mortality on chi-square analysis, P=0.01).

CONCLUSION

This study demonstrates that 4F-PCC is being utilized for indications other than the reversal of warfarin-induced coagulopathy. Further investigation is warranted to determine the efficacy and safety of 4F-PCC for these potential indications.

Propensity score adjusted comparison of three-factor versus four-factor prothrombin complex concentrate for emergent warfarin reversal: a retrospective cohort study

BACKGROUND

Prothrombin Complex Concentrates (PCC) are prescribed for emergent warfarin reversal (EWR). The comparative effectiveness and safety among PCC products are not fully understood.

METHODS

Patients in an academic level one trauma center who received PCC3 or PCC4 for EWR were identified. Patient characteristics, PCC dose and time of dose, pre- and post-INR and time of measurement, fresh frozen plasma and vitamin K doses, and patient outcomes were collected. Patients whose pre-PCC International Normalized Ratio (INR) was > 6 h before PCC dose or the pre-post PCC INR was > 12 h were excluded. The primary outcome was achieving an INR ≤ 1.5 post PCC. Secondary outcomes were the change in INR over time, post PCC INR, thromboembolic events (TE), and death during hospital stay. Logistic regression modelled the primary outcome with and without a propensity score adjustment accounting for age, sex, actual body weight, dose, initial INR value, and time between INR measurements. Data are reported as median (IQR) or n (%) with p < 0.05 considered significant.

RESULTS

Eighty patients were included (PCC3 = 57, PCC4 = 23). More PCC4 patients achieved goal INR (87.0% vs. 31.6%, odds ratio (OR) = 14.4, 95% CI: 3.80-54.93, p < 0.001). This result remained true after adjusting for possible confounders (AOR = 10.7, 95% CI: 2.17-51.24, p < 0.001). The post-PCC INR was lower in the PCC4 group (1.3 (1.3-1.5) vs. 1.7 (1.5-2.0)). The INR change was greater for PCC4 (2.3 (1.3-3.3) vs. 1.1 (0.6-2.0), p = 0.003). Death during hospital stay (p = 0.52) and TE (p = 1.00) were not significantly different.

CONCLUSIONS

PCC4 was associated with a higher achievement of goal INR than PCC3. This relationship was observed in the unadjusted and propensity score adjusted results.

Generation of hyperfunctional recombinant human factor IX variants expressed in human cell line SK-Hep-1

OBJECTIVE

To develop recombinant factor IX (FIX) variants with augmented clotting activity.

RESULTS

We generated three new variants, FIX-YKALW, FIX-ALL and FIX-LLW, expressed in SK-Hep-1 cells and characterized in vitro and in vivo. FIX-YKALW showed the highest antigen expression level among the variants (2.17 µg^-mL), followed by FIX-LLW (1.5 µg^-mL) and FIX-ALL (0.9 µg^-mL). The expression level of FIX variants was two-five fold lower than FIX-wild-type (FIX-WT) (4.37 µg^-mL). However, the biological activities of FIX variants were 15-31 times greater than FIX-WT in the chromogenic assay. Moreover, the new variants FIX-YKALW, FIX-LLW and FIX-ALL also presented higher specific activity than FIX-WT (17, 20 and 29-fold higher, respectively). FIX variants demonstrated a better clotting time than FIX-WT. In hemophilia B mice, we observed that FIX-YKALW promoted hemostatic protection.

CONCLUSION

We have developed three improved FIX proteins with potential for use in protein replacement therapy for hemophilia B.

The association between leptin concentration and blood coagulation: Results from the NEO study

BACKGROUND

The adipocyte-derived hormone leptin has been associated with altered blood coagulation in in vitro studies. However, it is unclear whether this association is relevant in vivo and to what extent this association is influenced by total body fat. Therefore, we aimed to examine the association between serum leptin and blood coagulation while taking total body fat into account in a population-based cohort study.

METHODS

We performed a cross-sectional analysis with baseline measurements of 5797 participants of the Netherlands Epidemiology of Obesity (NEO) study, a population-based cohort of middle-aged men and women. We examined associations between serum leptin concentration and coagulation factor concentrations and parameters of platelet activation in linear regression analyses. All analyses were adjusted for multiple covariates, including total body fat.

RESULTS

In multivariable adjusted analyses a 1 μg/L higher serum leptin concentration was associated with a 0.22 IU/dL (95% CI: 0.11, 0.32) higher FVIII concentration and a 0.20 IU/dL (95% CI: 0.14, 0.27) higher FIX concentration (3.5 IU/dL FVIII and 3.2 IU/dL FIX per SD leptin). Serum leptin concentration was not associated with FXI, fibrinogen, platelet count, mean platelet volume and platelet distribution width in multivariable adjusted analyses.

DISCUSSION

This study showed that serum leptin concentration was associated with higher concentrations of FVIII and FIX in an observational study, which could be clinically relevant.

Incidence of Symptomatic Venous Thromboembolism in Patients with Hemophilia Undergoing Hip and Knee Joint Replacement without Chemoprophylaxis: A Retrospective Study

OBJECTIVE

To establish the prevalence of clinically significant venous thromboembolic events (VTE) in hemophilia patients undergoing total hip arthroplasty (THA) and total knee arthroplasty (TKA) without chemoprophylaxis and a modified coagulation factor substitution.

METHODS

A cohort of patients who underwent THA and TKA from June 2002 to April 2017 were included. Based on World Federation of Hemophilia (WFH) guidelines, a modified coagulation factor substitution regimen was adopted. All patients were under a standardized postoperative protocol with routine mechanical prophylaxis against VTE. None of the patients received prophylactic anticoagulation. Only symptomatic patients were referred for radiological examination to exclude VTE. We evaluated the patient demographics and calculated the prevalence of VTE in our cohort.

RESULTS

A total of 98 patients were reviewed. The patients were all men. Thirty-one patients underwent primary THA with 39 hip arthroplasties (only 1 case with hemophilia B) and 67 patients underwent primary TKA with 101 knee arthroplasties (5 cases with hemophilia B). The mean age was 34.2 ± 7.8 years. The mean body mass index was 21.2 ± 5.7 kg/m² . There was 100% compliance to mechanical prophylaxis. The mean time to ambulation was 6.8 days (±2.5 days), and the mean hospital stay was 32.4 days (±7.1 days). There was only 1 hemophilia B patient with clinically significant VTE. None of the other 97 surgical cases had symptomatic VTE within 6 months after the procedure. This translates to a prevalence of 1.02%.

CONCLUSION

Given the low incidence (1.02%) of clinically significant VTE in our cohort, routine chemoprophylaxis in hemophilia patients undergoing THA and TKA may not be needed.

Emicizumab for routine prophylaxis to prevent bleeding episodes in patients with hemophilia A

Hemophilia A is an X-linked bleeding disorder caused by defects in the gene encoding factor VIII (FVIII). Routine prophylaxis with exogenous FVIII requires frequent intravenous injections. One of the most challenging issues in the treatment of hemophilia A is the development of alloantibodies against infused FVIII. Presence of inhibitors results in an ineffective factor replacement therapy and increases the risk of morbidity and mortality in these patients. Therefore, there is growing interest in the development of new strategies for the prophylaxis and prevention of bleeding in patients with hemophilia to circumvent these drawbacks. Emicizumab (ACE-910; Roche, Genentech and Chugai Pharmaceutical) is a recombinant humanized bispecific antibody that restores the function of missing FVIII by bridging activated FIX and FX, simulating the cofactor function of FVIII.

Outcome of perioperative hemostatic management in patients with hemophilia without inhibitors undergoing 161 invasive or surgical procedures

Perioperative management of persons with hemophilia (PWH) is a challenge for surgeons and hematologists. Reductions in mortality rate and complications have been achieved since the introduction of clotting factor concentrates (CFCs), which improve hemostatic control. However, there is no clear consensus on the optimal dosing of CFC administration. The aim of this study was to evaluate the outcome of PWH without inhibitors in patients undergoing invasive or surgical procedures. A total of 161 procedures, including 57 major and 104 minor ones were retrospectively reviewed. The characteristics of PWH, age at procedure, duration and total amount of CFC administration during the perioperative period, hemostatic adequacy, and complications were summarized. The study showed a low rate of bleeding (1.2%), infection (0%), thromboembolic event (0%), and inhibitor development (0%). The results revealed the doses and duration of CFC administration for several major and minor procedures which were capable of achieving excellent hemostatic control.

[Hemorrhage under direct oral anticoagulants : Occurrence and treatment in intensive care patients]

The use of anticoagulants is associated with an increased risk of bleeding and nevertheless bleeding complications can be lifethreatening. The focus is on bleeding under direct oral anticoagulants (DOAC) because antidotes and specific measures are lacking for some DOACs. Furthermore, routinely carried out clotting tests cannot be used to determine the degree of anticoagulation under DOACs. Therefore, it becomes difficult to determine whether the coagulation inhibition effect is present. This article presents the treatment of hemorrhage in patients with DOACs in the intensive care unit. Further, the indications for DOACS and details of administration and monitoring are presented.

Prothrombotic factors do not increase the risk of recurrent ischemic events after cryptogenic stroke at young age: the FUTURE study

BACKGROUND

The role of hypercoagulable states and preceding infections in the etiology of young stroke and their role in developing recurrent ischemic events remains unclear. Our aim is to determine the prevalence of these conditions in patients with cryptogenic stroke at young age and to assess the long-term risk of recurrent ischemic events in patients with and without a hypercoagulable state or a recent pre-stroke infection with Borrelia or Syphilis.

PATIENTS AND METHODS

We prospectively included patients with a first-ever transient ischemic attack or ischemic stroke, aged 18-50, admitted to our hospital between 1995 and 2010. A retrospective analysis was conducted of prothrombotic factors and preceding infections. Outcome was recurrent ischemic events.

RESULTS

Prevalence of prothrombotic factors did not significantly differ between patients with a cryptogenic stroke and with an identified cause (24/120 (20.0%) and 32/174 (18.4%) respectively). In patients with a cryptogenic stroke the long-term risk [mean follow-up of 8.9 years (SD 4.6)] of any recurrent ischemic event or recurrent cerebral ischemia did not significantly differ between patients with and without a hypercoagulable state or a recent infection. In patients with a cryptogenic stroke 15-years cumulative risk of any recurrent ischemic event was 24 and 23% in patients with and without any prothrombotic factor respectively.

CONCLUSIONS

The prevalence of prothrombotic factors and preceding infections did not significantly differ between stroke patients with a cryptogenic versus an identified cause of stroke and neither is significantly associated with an increased risk of recurrent ischemic events after cryptogenic stroke.

[Vomiting and collapse of a 28-year-old male long distance runner in middle European Summer]

BACKGROUND

Hyperthermia often ends fatally and must therefore be promptly recognized and adequately treated.

CASE

A 28-year-old man participated in a long-distance race (3 km) on a hot summer day (28 °C). The runner collapsed, had to vomit but continued the run and reached the finish. Neurologically, the patient presented with intermittent cerebral seizures. External cooling batteries were immediately applied and cold infusions were started. The patient was admitted to the intensive care unit of the university hospital (body temperature 40.2 °C). After a few hours, a manifest disseminated intravascular coagulopathy developed with multiple organ failure. It took 12 l of volume replacement, 8 units of fresh frozen plasma and 2 units of erythrocyte concentrates in the first 12 h to stabilize the patient. Although with the help of forced external cooling and application of cold infusions, the body temperature could be lowered to 38 °C by the next morning, the overall situation of the patient continued to deteriorate. Despite dialysis and massive substitution of coagulation factors, the patient could not be sufficiently stabilized and died of brain edema.

CONCLUSION

Not only the old or young children are subject to the potential danger of a fatal heat stroke but also young athletic persons after normal sports activities (3 km run). Cooling must be started immediately and the patient must be hospitalized as a vital emergency. If hemostasis fails due to the heat-related loss of hepatogenic protein synthesis, a viscious circle begins, which, as in the reported case, is irreversible despite maximum therapy and substitution.

Comparison of drug administration logistics between prothrombin complex concentrates and plasma in the emergency department

BACKGROUND

Prothrombin complex concentrate (PCC) is used as an alternative to fresh frozen plasma (FFP) for emergency bleeding. The primary objective of this study was to compare the time from order to start of administration between 3-factor PCC (PCC3), 4-factor (PCC4), and FFP in the emergency department (ED). The secondary objective was to evaluate the effect of an ED pharmacist on time to administration of PCCs.

METHODS

This was a single center three-arm retrospective cohort study. Adult patients in the ED with bleeding were included. The primary outcome measure was the time from order to administration, which was compared between PCC3, PCC4, and FFP. The time from order to administration was also compared when the ED pharmacist was involved versus not involved in the care of patients receiving PCC.

RESULTS

There were 90 patients included in the study cohort (30 in each group). The median age was 69years (IQR 57-82years), and 57% (n=52) were male. The median time from order to administration was 36min (IQR 20-58min) for PCC3, 34min (IQR 18-48min) for PCC4, and 92min (IQR 63-133) for FFP (PCC3 versus PCC4, p=0.429; PCC3 versus FFP, p<0.001; PCC4 versus FFP, p<0.001). The median time from order to administration was significantly decreased when the ED pharmacist was involved (24min [IQR 15-35min] versus 42min [IQR 32-59min], p<0.001).

CONCLUSIONS

Time from order to administration is faster with PCC than FFP. ED pharmacist involvement decreases the time from order to administration of PCC.

The anticoagulant properties of cadmium telluride quantum dots

The size-dependent optical properties of quantum dots (QDs) are frequently exploited for use in medical imaging and labelling applications. Similarly, presented here, they also elicit profound size-dependent anticoagulant properties. Cadmium telluride quantum dot (QDs) (3.2 nm) were shown to have a dramatic anticoagulant effect centred on around the intrinsic coagulation pathway, compared to their 3.6 nm counterparts. Several clinically relevant diagnostic tests were carried out over a concentration range of the QDs and demonstrated that the 3.2 nm QDs elicited their response on the intrinsic pathway as a whole, yet the activity of the individual intrinsic coagulation factors was not affected. The mechanism appears also to be strongly influenced by the concentration of calcium ions and not cadmium ions leached from the QDs. Static and shear-based primary haemostasis assays were also carried out, demonstrating a profound anticoagulant effect which was independent of platelets and phospholipids. The data presented here suggest that the physical-chemical properties of the QDs may have a role in the modulation of haemostasis and the coagulation cascade, in a yet not fully understood mechanism. This study has implications for the use of similar QDs as diagnostic or therapeutic tools in vivo, and for the occupational health and safety of those working with such materials.

Association of pre-chemotherapy peripheral blood pro-inflammatory and coagulation factors with reduced relative dose intensity in women with breast cancer

Background

Chemotherapy decreases the risk of relapse and mortality in early-stage breast cancer (BC), but it comes with the risk of toxicity. Chemotherapy efficacy depends on relative dose intensity (RDI), and an RDI < 85% is associated with worse overall survival. The pro-inflammatory (interleukin (IL)-6, C-reactive protein (CRP)) and coagulation factors (D-dimer) serve as biomarkers of aging. The purpose of this study is to determine if these biomarkers are associated with reduced RDI in women with stage I–III BC.

Methods

This study enrolled women with stage I–III BC. Prior to adjuvant or neoadjuvant chemotherapy, peripheral blood was collected for biomarker measurement. Dose reductions and delays were captured and utilized to calculate the RDI delivered. Univariate and multivariate analyses were performed to describe the association between pre-chemotherapy IL-6, CRP, and D-dimer levels and an RDI < 85%, controlling for relevant tumor and patient factors (age, stage, receptor status, chemotherapy regimen, and pre-chemotherapy physical function and comorbidity).

Results

A total of 159 patients (mean age 58 years, range 30–81, SD 11.3) with stage I–III BC were enrolled. An RDI < 85% occurred in 22.6% (N = 36) of patients and was associated with higher pre-chemotherapy IL-6 (OR 1.14, 95% CI 1.04–1.25; p = 0.006) and D-dimer (OR 2.32, 95% CI 1.27–4.24; p = 0.006) levels, increased age (p = 0.001), increased number of comorbidities (p = 0.01), and decreased physical function by the Medical Outcomes Survey Activities of Daily Living (ADL) Scale (p = 0.009) in univariate analysis. A multivariate model, including two biomarkers (IL-6 and D-dimer), age, ADL, BC stage, and chemotherapy regimen, demonstrated a significant association between the increased biomarkers and reduced RDI < 85% (OR 2.54; p = 0.04).

Conclusions

Increased pre-chemotherapy biomarkers of aging (IL-6 and D-dimer) are associated with reduced RDI (<85%). Future studies are underway to validate these findings.

Trial registration

ClinicalTrials.gov, NCT01030250. Registered on 3 November 2016.

Electronic supplementary material

The online version of this article (doi:10.1186/s13058-017-0895-5) contains supplementary material, which is available to authorized users.

[NOAC: Real-life data and the role of antidotes for the treatment of bleeding]

The non-vitamin K antagonists (NOAC) are an integral component of our antithrombotic prevention and therapy. For four of the NOAC, their non-inferiority or even superiority versus vitamin K antagonists (VKA) has been proven. Thus, the management of special patient cohorts or the management of active bleeding complications is a focus of current discussion.In addition to prospective trials, numerous retrospective analyses of health insurers or public health provider data have been analyzed and published as "real life" or "real-world evidence" data. In almost all data sets the results of the NOAC approval trials were confirmed, demonstrating their non-inferiority or even superiority versus VKA. Attempts to compare the various NOAC with each other must be viewed critically since the real-world evidence (RWE) analysis provides very divergent results depending on the cohorts analyzed. Thus, a substantial prescriber-bias must be taken into account and never be excluded.In order to improve the management of bleeding complications, NOAC antidotes were developed. While the factors Xa antidote, andexanet alpha, a modified coagulation factor deleted of an intrinsic activity, will not be available before 2018, the dabigatran antidote idarucizumab is already in clinical use. Idarucizumab, a monoclonal antibody fragment directed against dabigatran, is able to completely antagonize the effect of dabigatran within minutes. Therefore, the drug has the potential to terminate life-threatening bleeding complications earlier and make emergency surgical or interventional procedures possible without an elevated bleeding risk.

Coagulative safety of epidural catheters after major upper gastrointestinal surgery: advanced and routine coagulation analysis in 38 patients

BACKGROUND

The risk of spinal haematoma in patients receiving epidural catheters is estimated using routine coagulation tests, but guidelines are inconsistent in their recommendations on what to do when results indicate slight hypocoagulation. Postoperative patients are prone to thrombosis, and thromboelastometry has previously shown hypercoagulation in this setting. We aimed to better understand perioperative haemostasis by comparing results from routine and advanced tests, hypothesizing that patients undergoing major upper gastrointestinal surgery would be deficient in vitamin K-dependent coagulation factors because of malnutrition, or hypocoagulative because of accumulation of low molecular weight heparin (LMWH).

METHODS

Thirty-eight patients receiving epidural analgesia for major upper gastrointestinal surgery were included. We took blood at the time of preoperative epidural catheterization and at catheter withdrawal. Prothrombin time-international normalized ratio (PT-INR), activated partial thromboplastin time (aPTT) and platelet count (Plc) were analysed, and also albumin, proteins induced by vitamin K absence (PIVKA-II), rotational thromboelastometry (ROTEM®), multiple electrode aggregometry (Multiplate®) and activities of factors II, VII, IX, X, XI, XII and XIII.

RESULTS

Postoperative coagulation was characterized by thrombocytosis and hyperfibrinogenaemia. Mean PT-INR increased significantly from 1.0 ± 0.1 to 1.2 ± 0.2 and mean aPTT increased significantly from 27 ± 3 to 30 ± 4 s. Activity of vitamin K-dependent factors did not decrease significantly: FIX and FX activity increased. FXII and FXIII decreased significantly. Mean Plc increased from 213 ± 153 × 10⁶/L while all mean ROTEM-MCFs (maximal clot firmnesses) especially FIBTEM-MCF increased significantly to above the reference interval. All mean ROTEM® clotting times were within their reference intervals both before and after surgery. ROTEM® (HEPTEM minus INTEM) results were spread around 0. There were significant correlations between routine tests and the expected coagulation factors, but not any of the viscoelastic parameters or PIVKA-II. Multiplate® area under curve and EXTEM-MCF correlated significantly to Plc as did EXTEM-MCF to fibrinogen, FIX, FX and FXIII; and FIBTEM-MCF to Plc, FII, FXI and FXIII.

CONCLUSIONS

The increase in PT-INR may be caused by decreased postoperative FVII while the elevated aPTT may be caused by low FXII. The mild postoperative hypocoagulation indicated by routine tests is not consistent with thromboelastometry. The relevance of ROTEM® and Multiplate® in the context of moderately increased routine tests remains unclear. Trial registration number is not applicable since this is not a clinical trial.

[Therapy with blood products]

Blood products are frequently used in intensive care medicine although there is little evidence of improvement in clinical outcome. The threshold for erythrocyte transfusion in non-bleeding critically ill patients is currently a hemoglobin level of 7.0 g/dl. The indications for platelet transfusion must be assessed after evaluation of the cause of thrombocytopenia, the clinical condition and the expected effect. The use of plasma should also be critically viewed, mainly due to hypervolemia. Prothrombin complex concentrates are better than plasma for warfarin reversal. There is good evidence for the use of albumin for massive paracentesis, in the treatment of hepatorenal syndrome type 1 and spontaneous bacterial peritonitis. Albumin infusion can have favorable effects in severe sepsis and septic shock. A restrictive strategy should be favored in the use of blood products and the decision should be based on a critical appraisal of the available evidence.

Influence of blood lipids on global coagulation test results

Background

High levels of blood lipids have been associated with high levels of coagulation factors. We investigated whether blood lipids influence the results of global coagulation tests, including prothrombin time (PT), activated partial thromboplastin time (aPTT), and thrombin generation assay (TGA).

Methods

PT, aPTT, and TGA, along with procoagulant and anticoagulant factors, were measured in 488 normal individuals. Vitamin K status was assessed with prothrombin-induced by vitamin K absence-II (PIVKA-II).

Results

The procoagulant factors II, VII, IX, X, and XI and anticoagulant factors protein C and protein S showed significant correlations with triglyceride, and the procoagulant factors II, V, VII, IX, X, XI, and XII and anticoagulant factors antithrombin and protein C correlated with total cholesterol. There were no correlations of blood lipid levels with PIVKA-II levels. Subjects with high triglyceride levels (≥200 mg/dL) showed shorter PT values than those with lower triglyceride levels. However, aPTT value was not changed in terms of blood lipid levels. In both 1 and 5 pM tissue factor-induced TGAs, subjects in the high-triglyceride or high-cholesterol groups (≥240 mg/dL) had high levels of lag time, time-to-peak, and endogenous thrombin potential. Total cholesterol was a significant determinant of PT and TGA values.

Conclusion

High blood lipids were related with increased coagulation activity in a normal population. Our findings are expected to help interpret the global coagulation test results in individuals with high lipid levels.

Evaluation of the plasma quality after filtration

BACKGROUND AND THE PURPOSE OF THE STUDY

The quality of some of the human plasma derived drugs such as coagulation factor VIII and coagulation factor IX which can be used for the treatment of hemophilia A and B, depends on their activity which may be affected by filtration. In this study the quality of plasma with respect to coagulation factors FVII, FVIII, FIX, FV, FXI, Fibrinogen, antithrombin III, anti-plasmin and antitrypsin activities obtained after plasma filtration with CPD (citrate-phosphate-dextrose) using integral filter was evaluated.

METHODS

Sixty units of plasma were individually separated from whole blood by centrifugation and immediately filtered by integral filter system. Specific plasma filtration was carried out between 4 and 20 hrs after blood donation. Before filtration, 60 units of non filtered fresh plasmas were kept as control. Coagulation factors were determined by one-stage clotting assay in an automated system. Antithrombin III activity was determined by immunochrom assay in an automated system. Activity of anti-plasmin was determined by Berichrom α(2)-antiplasmin and antitrypsin activity was assayed with human neutrophil elastase.

RESULTS

The activity of coagulation factors FVIII, FIX, Fibrinogen, FV, and FXI, were not affected by filtration, in all experiments. Filtration only caused negligible change in FVII activity. Antithrombin III, anti-plasmin and antitrypsin activities were not influenced by filtration. Nonfiltrated and filtrated plasma values were not significantly different (P> 0.05).

CONCLUSIONS

Plasma filtration dose not result in a measurable impairment of coagulation factors and inhibitors. Although a little changes in FVII activity was observed after filtration, but these filtration-dependent changes apparently have no impact on the therapeutic quality of whole blood- filtered fresh plasma for transfusion.