Mild Bleeding Disorders Research Articles

Patients Referred for Bleeding Symptoms of Unknown Cause: Does Evaluation of Thrombin Generation Contribute to Diagnosis?

IntroductionPatients with mild to moderate bleeding symptoms referred for coagulation investigation sometimes never receive a definitive diagnosis. Bleed assessment tools have been developed and validated to assess the severity of symptoms. Global coagulation assays, e.g., the thrombin generation test (thrombogram) have a potential to identify hemostatic defects that are not detected in specific assays.Material and MethodsOne hundred and eighty-five patients referred to our centre because of bleeding symptoms were evaluated using the bleeding assessment tool (BAT) described by Tosetto and colleagues in 2006. Blood samples were investigated for thrombin generation (TG) capacity (Technoclone), in platelet poor (PPP) plasma, and specific clotting factors, i.e., von Willebrand factor, factor VIII and IX, as well as INR, APTT, platelet count, and platelet adhesion.ResultsOf the 185 patients, five women were diagnosed with mild von Willebrand disease and one male with mild hemophilia A. The remaining 179 subjects (76% females and 24% males with average ages of 33 and 28 years, respectively) were evaluated further. In the total cohort and among women, peak TG, and lag time correlated with bleeding score (p=0.01 and p=0.04, respectively with correlation coefficients). No such correlations were found among males.Discussion and ConclusionAlthough our study showed some correlation between TG and bleeding score, results are generally consistent with a previous report which failed to demonstrate the value of TG measurement in a similar setting. In conclusion, the complexity of the mechanisms underlying clinical bleeding complicates the ability to use TG tests as reliable predictors of bleeding. Mild congenital bleeding disorders, especially VWD, should be specifically screened for in patients with mild/moderate symptoms.

The Diagnostic Accuracy of Bleeding Assessment Tools for the Identification of Patients with Mild Bleeding Disorders: A Systematic Review

IntroductionA study of diagnostic test accuracy compares a single index test to a gold standard to determine status of disease. The observed accuracy of a test varies among patient subgroups and is sensitive to bias. To achieve reliable estimates of diagnostic accuracy, an appropriate study design in a clinically relevant population is warranted. Recently a review was published about the evolution of the bleeding assessment tool (BAT) in diagnosing patients with mild bleeding disorders (MBD) (Rydz et al. J Thromb Haemost 2012). Many validation studies have been done. However, a critical appraisal addressing the quality of these validation studies is lacking.ObjectiveWe performed a systematic review to determine the quality and applicability of studies assessing the diagnostic utility of the BAT for MBD among clinic based cohorts.MethodsThe literature search was conducted using the electronic database PubMed. The final search date was March 2, 2015. The search terms: 'bleeding disorder OR bleeding tendency' AND 'bleeding questionnaire' were used. All studies assessing the diagnostic accuracy of bleeding questionnaires in identifying adults (age > 18 years) with MBD were considered eligible, irrespective of study design or used reference standard. The methodological quality and applicability of each included study was assessed using a Quality Assessment of Diagnostic studies-2 (QUADAS-2) tool. This tool consists of four domains specific for patient selection, index test, reference standard and participant flow. For each domain bias was assessed using signaling questions, for the first three domains applicability was assessed.ResultsThe search yielded 530 citations, from which 35 possible relevant full-text studies were identified. Twenty-two studies were excluded, reasons for exclusion were: letter to the editor, validation of questionnaire combined with laboratory results and primary care population. Table 1 shows the 13 included studies, the assessed BAT and the targeted bleeding condition. Risk of bias and applicability concerns are summarized in figure 1. In 77% of the studies there was a high risk of bias for patient selection and applicability concerns. Many studies used a case control design, comparing patients with a known bleeding disorder with healthy controls. This leads to spectrum bias and might generate higher estimates of sensitivity and specificity (Rutjes et al. Clin Chem 2005). In 46% there was a high risk of bias for index test due to the use of a self-administered questionnaire or because the person conducting the questionnaire was aware of the diagnosis. This leads to observer bias caused by better awareness and over-reporting of bleeding symptoms. Finally, there was high risk of bias in study flow in 38% of the studies. These studies included symptoms after diagnosis of the bleeding disorder. Since bleeding disorders are managed by interventions to prevent bleeding, underestimation of the bleeding symptoms may occur.ConclusionThis review highlights the difficulties and advantages of the BAT validation studies. It provides the ability for medical practitioners to apply the BAT with full awareness of its restrictions and benefits. With the evaluation of the risks of bias in the included studies we highlighted limitations, especially in method of patient selection and use of index test, that future studies preferably should try to avoid. [Display omitted] [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Flow Cytometry-Based Platelet Function Testing Is Predictive of Symptom Burden in a Cohort of Bleeders

▪Platelet function disorders (PFDs) are common in patients with mild bleeding disorders (MBDs), yet the clinical significance of laboratory findings suggestive of a PFD remain unclear due to the lack of evidence for a clear link between test results and patient phenotype. Herein, we present results from a study evaluating the potential utility of platelet function testing using whole-blood flow cytometry in a cohort of 105 patients undergoing investigation for MBD. Subjects were evaluated with a test panel comprising two different activation markers (fibrinogen binding and p-selectin exposure) and four physiologically relevant platelet agonists (ADP, PAR1-AP, PAR4-AP and CRP-XL). Abnormal test results were identified by comparison with reference ranges constructed from 24 healthy controls or the fifth percentile of the entire patient sample. We found that abnormal test results are predictive of bleeding symptom severity, and that the greatest predictive strength was achieved using a subset of the panel, comparing measurements of fibrinogen binding after activation with all four agonists with the fifth percentile of the patient sample (P = 0.00008, hazard ratio 8.7; 95 % CI 2.5-40). Our results suggest that whole-blood flow cytometry-based platelet function testing is a feasible alternative for the investigation of MBDs. We also show that platelet function testing using whole-blood flow cytometry could provide a clinically relevant quantitative assessment of platelet-related primary hemostasis. [Display omitted] DisclosuresLindahl:Diapensia: Equity Ownership.

TMEM16F is required for phosphatidylserine exposure and microparticle release in activated mouse platelets

Phosphatidylserine (PtdSer) exposure on the surface of activated platelets requires the action of a phospholipid scramblase(s), and serves as a scaffold for the assembly of the tenase and prothrombinase complexes involved in blood coagulation. Here, we found that the activation of mouse platelets with thrombin/collagen or Ca(2+) ionophore at 20 °C induces PtdSer exposure without compromising plasma membrane integrity. Among five transmembrane protein 16 (TMEM16) members that support Ca(2+)-dependent phospholipid scrambling, TMEM16F was the only one that showed high expression in mouse platelets. Platelets from platelet-specific TMEM16F-deficient mice exhibited defects in activation-induced PtdSer exposure and microparticle shedding, although α-granule and dense granule release remained intact. The rate of tissue factor-induced thrombin generation by TMEM16F-deficient platelets was severely reduced, whereas thrombin-induced clot retraction was unaffected. The imaging of laser-induced thrombus formation in whole animals showed that PtdSer exposure on aggregated platelets was TMEM16F-dependent in vivo. The phenotypes of the platelet-specific TMEM16F-null mice resemble those of patients with Scott syndrome, a mild bleeding disorder, indicating that these mice may provide a useful model for human Scott syndrome.

Plasma clot properties in patients with a mild-to-moderate bleeding tendency of unknown cause.

In a large proportion of patients with mild bleeding disorders (MBDs) no diagnosis can be established by routine coagulation tests. We investigated whether alterations in plasma clot properties account for MBDs of unknown cause. Ninety-five patients with MBDs of unknown origin and 98 age- and sex-matched healthy controls were investigated. Furthermore, data of 25 patients with a deficiency of factor VIII were analyzed. Plasma clot characteristics in the absence and presence of recombinant tissue plasminogen activator (rtPA) represented by the lag phase, rate of protofibril formation (Vmax), fibrin structure (ΔAbs), time to peak (TTP), half lysis time (t50 and area under the curve (AUC) were measured in turbidometric clot formation and lysis assays. In the fibrinolysis assay, Vmax was lower in patients than in healthy controls. No differences in the other parameters of clot formation and lysis were detected between the groups. There was no clear association of plasma clot properties with the clinical severity of bleeding in patients with MBDs. Patients with known decreased factor VIII levels also showed a lower Vmax. Fibrinogen levels were positively associated with each of the assessed parameters in both groups, with the strongest association with ΔAbs, indicating altered fibrin structure. Factor VIII activity correlated with altered clot characteristics similar to fibrinogen, especially in patients, with the strongest positive correlation to Vmax. This cohort of patients with MBDs of unknown origin showed a lower rate of fibrin formation in the fibrinolysis assay, but otherwise similar plasma clot properties compared to healthy controls.

Referral Practices in Management of Heavy Menstrual Bleeding in Adolescents

▪Background: Due to the prevalence of mild bleeding disorders (MBDs) among adolescent females with heavy menstrual bleeding (HMB), the American College of Obstetricians and Gynecologists (ACOG) and the American Academy of Pediatrics (AAP) recommend screening select adolescent patients with HMB for mild bleeding disorders (MBDs) under the guidance of a hematologist, as coagulation labs can be difficult to interpret. The goal of this study was to describe referral patterns for adolescents with HMB and compare evaluation and management practices among different pediatric specialties using Medicaid claims data.Methods: Our patient population comprised 10-17 year old females enrolled in Medicaid in central and southeastern Ohio with at least 2 separate diagnoses of HMB and at least 12 months of continuous enrollment prior to their first HMB diagnosis. While there is no standard definition of “severe” HMB, for this study, patients with iron deficiency anemia, an inpatient hospital stay for HMB, or an outpatient blood transfusion were defined as having severe HMB. Medicaid claims data and electronic medical records from Nationwide Children’s Hospital, the region’s only children’s hospital, were linked to collect study data.Results: We identified 509 patients with HMB. Referral to a pediatric specialist occurred in 17.9% of patients; 39.5% of those with severe HMB and 13.8% of those with non-severe HMB were referred. 10.8% of patients were referred to adolescent med, 6.7% were referred to hematology, and 0.4% were referred to endocrinology. Of the patients seen by a specialist at a children’s hospital, 69% were screened for a MBD. When stratified by specialty, 100.0% of patients seen by hematology were screened for a MBD while 51.0% of patients seen by adolescent medicine were screened for a MBD. Approximately one-third (35.7%) of referred patients were diagnosed with a MBD, most commonly platelet function defects and von Willebrand disease (VWD). 48.3% of patients with severe HMB were diagnosed with a MBD, while 29.1% of patients with non-severe HMB were diagnosed with a MBD. Both hematologists (100.0%) and adolescent medicine doctors (97.0%) almost uniformly prescribed treatment for HMB, most commonly hormonal contraception (95.2%). Patients had significantly higher odds of referral to a pediatric specialist if they had severe HMB [2.3, 95% CI (1.42-3.71)]. Patients had significantly lower odds of referral if they lived farther away from the region’s children’s hospital [0.16, 95% CI: (0.09-0.29)]. There was no significant difference in frequency of referral between patients initially diagnosed by family practitioners, pediatricians, or gynecologists.Conclusions: Despite ACOG and AAP recommendations, we found that only a small percentage of adolescents with HMB are referred to a pediatric specialist. Efforts should be made to increase education regarding which patients are at higher risk of an underlying MBD, and increasing the number of these adolescents who are referred to hematology so that coagulation lab studies can be ordered and interpreted appropriately. Such efforts should be targeted at patients in rural areas, since this population was particularly unlikely to receive care from a hematologist. DisclosuresNo relevant conflicts of interest to declare.

Elucidation of Mild Bleeding Disorders Reported Under Ibrutinib (Imbruvica(R)) Therapy: Implications for Optimal Clinical Management

IntroductionIbrutinib is the first-in-class covalent inhibitor of Bruton’s Tyrosine Kinase (BTK), now approved for the therapy of mantle cell lymphoma (MCL) and chronic lymphocytic leukemia (CLL). Mild bleeding disorders (grade 1-2) have been reported in 44-60% of patients across clinical trials, with <5% grade 3 hemorrhages after trauma. After vascular injury, platelets adhere onto von Willebrand factor (vWF, through GPIb-IX-V complex) and collagen (through a2b1 and GPVI receptor), and activate phospholipase Cg2 (PLCg2) through BTK phosphorylation. In this study, we sought to examine phosphorylation pathways and platelet functions in vitro and ex vivo from ibrutinib-treated patients.Patients and MethodsWithin the compassionate access program of ibrutinib in France (started Feb 2014), we investigated whether ibrutinib could impact on platelet functions in vitro and ex vivo, as measured at day 0 and day 15-30 by: aggregometry using various agonists, measurement of intra-cellular levels of phosphorylation of BTK and PLCg2 phosphorylations, monitoring adhesion onto vWF matrix under high shear rate.We next assess how in vitro tests could help identify bleeding risk in a larger cohort of patients from three institutions.ResultsFirst, we demonstrated that in healthy donors’ platelets, ibrutinib inhibits collagen and collagen related peptide (CRP) -induced platelet aggregation in a dose-dependent manner (mean EC50=250nM, a dose achievable in patients). This effect was paralleled by the inhibition of PLCg2 phosphorylation on the Btk-dependent phosphorylation site Tyr753, and of the auto-phosphorylation Tyr223 site of BTK itself, suggesting a specific targeting by ibrutinib. Of note, adhesion on vWF under high shear rate was dramatically decreased. In parallel, in 7/14 patients had bleeding symptoms (5/7 with grade 1-2 bleedings) and they all presented a strong inhibition of platelet aggregation in response to collagen and a significant decrease in adhesion onto vWF. Thus, the easy-to-use collagen-induced platelet aggregation test in platelet rich plasma could help physicians to decide when to perform surgical procedures without haemostasis concerns. Moreover, we show that addition of 50% untreated platelets is sufficient to efficiently reverse the effects of ibrutinib, and that platelet functions recover following treatment interruption as physiological platelet renewal occurs, supporting the in vitro data. On the other hand, patients who received aspirin (n=6) had no cases of severe bleeding and no significant impact on collagen/CRP-induced platelet aggregation. Because aspirin+P2Y12 inhibitors (such as clopidogrel, Plavix®) is widely used in the elderly population, ibrutinib therapy should be given very cautiously to these patients (who receive then three major pathway platelet activation pathway inhibitor), as recommended for vitamin K antagonists drugs. Aggregometry tests may provide important information to physicians to predict the bleeding risk as observed in our cohort of >30 patients (as of June 2014, recruitment still ongoing). Two last points should be emphasized when considering bleeding risk of ibrutinib: (i) from our study, some patients had no anti-platelet detectable effect ex vivo under ibrutinib therapy, the mechanism of which still remains unclear, and (ii) in patients with mild bleedings, platelet functions recovery and cessation of symptoms occured in virtually all patients (except those on aspirin therapy) after 3-6 months despite ongoing lymphoma responses, suggesting a potential adaptative process in platelets.Summary and ConclusionWe identified that ibrutinib affects collagen and Von Willebrand Factor-mediated platelet activation in vitro and ex vivo. The mild bleeding diathesis observed in a subgroup of ibrutinib-treated patients correlates with defects in collagen-induced platelet aggregation and platelet adhesion on von Willebrand Factor at high shear rate. Based on in vitro analyses and in vivo platelet turnover, 2-3 days ibrutinib cessation appears to be enough for effective aggregation response recovery, and reintroduction of the drug should be rapid to avoid disease recurrence. Our study also suggests that platelet transfusion at a dose sufficient to get 50 % of fresh platelets may correct haemostasis in emergency, provided it was given after elimination of ibrutinib from blood (4-6h). DisclosuresTam:Pharmacyclics and Janssen: Honoraria, Membership on an entity’s Board of Directors or advisory committees.

Reference Ranges of Coagulation Parameters in Pregnancies of Healthy Women and Women with Mild Bleeding Disorders

Introduction:It is well know that most of the coagulation factor increase during pregnancy in healthy women. Nevertheless the uninterrupted course of coagulation parameters from the beginning until the end of a pregnancy in healthy women has not been described yet. Only reference ranges for the third month and the sixth month of pregnancy are evaluated. There aren’t any data available for the course of coagulation parameters during pregnancy in women with known coagulation disorders.In 2012 we started a study to investigate reference ranges during pregnancy for all coagulation factors, anticoagulants and activation markers of coagulation in 100 healthy pregnant women and 100 pregnant women with a previously known mild bleeding disorders.The study has been approved by the Ethics Committee Nordrhein.Samples and Methods:We analysed samples of pregnant women by conducting the following tests: Blood count, VWF:RCo, VWF:Ag, VWF:CB, Fibrinogen (Clauss), activities of FII, FV, FVII, FVIII (clotting and chromogenic), FIX, FX, FXI, FXII, FXIII. d-dimer, prothrombin fragment 1.2, Quick, partial thromboplastin time, plasma thrombin time , CRP, proteine S, proteine C, antithrombin, Lupus antigoaculant, ACA, ß2-GP in week 10, 16, 22, 28, 34, 40 and 6 weeks post partum (max. +/- 1)Interim Results:Currently 21 pregnant women were included in our study. 16 obviously healthy women were used to calculate the reference ranges for pregnancy. Because of strict inclusion and exclusion criteria (no previous spontaneous abortion, no previous placenta haematoma, no previous pre-eclampsia and only natural pregnancies) most of the women are in the group of the no known coagulation disorder so far.Discussion/Conclusion:There are signs that defects in the coagulation system can be associated to complications during pregnancy like child loss, intrauterine haematoma and genital bleeding. The evaluation of reference ranges helps to detect and to value coagulation disorders during pregnancy.It might be possible to explain the higher abortion rate in women with mild bleeding disordersby determination of reference values of all pro- and anticoagulants during pregnancy. If a treatment with coagulation factor concentrates can help to prevent miscarriage is still subject of ongoing studies.Determination of reference ranges for coagulation factors in the third trimenon might help to determine the peripartum bleeding risk of women with mild coagulation disorders and to help to decide whether a women needs coagulation factor concentrate during labour.Limitation:Based on the strict inclusion and exclusion criteria the number of patients is small. DisclosuresHalimeh:Biotest: The authors declare that they receive research grant from Biotest AG Other. Rott:Biotest: The authors declare that they receive research grant from Biotest AG Other. Osseiran:Biotest: The authors declare that they receive research grant from Biotest AG Other. Kappert:Biotest: The authors declare that they receive research grant from Biotest AG Other. Siebert:Biotest: The authors declare that they receive research grant from Biotest AG Other.

Rare platelet GPCR variants: what can we learn?

Platelet-expressed GPCRs are critical regulators of platelet function. Pharmacological blockade of these receptors forms a powerful therapeutic tool in the treatment and prevention of arterial thrombosis associated with coronary atherosclerosis and ischaemic stroke. However, anti-thrombotic drug therapy is associated with high inter-patient variability in therapeutic response and adverse bleeding side effects. In order to optimize the use of existing anti-platelet drugs and to develop new therapies, more detailed knowledge is required relating to the molecular mechanisms that regulate GPCR and therefore platelet function. One approach has been to identify rare, function-disrupting mutations within key platelet proteins in patients with bleeding disorders. In this review, we describe how an integrated functional genomics strategy has contributed important structure-function information about platelet GPCRs with specific emphasis upon purinergic and thromboxane A2 receptors. We also discuss the potential implications these findings have for pharmacotherapy and for understanding the molecular basis of mild bleeding disorders.

The accuracy of a patient or parent-administered bleeding assessment tool administered in a paediatric haematology clinic.

Classifying and describing bleeding symptoms is essential in the diagnosis and management of patients with mild bleeding disorders (MBDs). There has been increased interest in the use of bleeding assessment tools (BATs) to more objectively quantify the presence and severity of bleeding symptoms. To date, the administration of BATs has been performed almost exclusively by clinicians; the accuracy of a parent-proxy BAT has not been studied. Our objective was to determine the accuracy of a parent-administered BAT by measuring the level of agreement between parent and clinician responses to the Condensed MCMDM-1VWD Bleeding Questionnaire. Our cross-sectional study included children 0-21 years presenting to a haematology clinic for initial evaluation of a suspected MBD or follow-up evaluation of a previously diagnosed MBD. The parent/caregiver completed a modified version of the BAT; the clinician separately completed the BAT through interview. The mean parent-report bleeding score (BS) was 6.09 (range: -2 to 25); the mean clinician report BS was 4.54 (range: -1 to 17). The mean percentage of agreement across all bleeding symptoms was 78% (mean κ=0.40; Gwet's AC1=0.74). Eighty percent of the population had an abnormal BS (defined as ≥2) when rated by parents and 76% had an abnormal score when rated by clinicians (86% agreement, κ=0.59, Gwet's AC1=0.79). While parents tended to over-report bleeding as compared to clinicians, overall, BSs were similar between groups. These results lend support for further study of a modified proxy-report BAT as a clinical and research tool.

Comprehensive Evaluation of Hemostasis in Normal Women

Women with mild bleeding disorders (MBDs) pose a diagnostic challenge and menorrhagia, the most common presenting symptom that remains underreported. We tested the hypothesis that screening apparently normal females using general and gynecological bleeding assessment tools and a global hemostatic assay together with platelet aggregation can help predict MBDs. We assessed 47 women using electronic bleeding assessment tools; e-bleeding questionnaire; and e-Pictorial Bleeding Assessment Chart (e-PBAC) based on previously validated methods, thrombelastography (TEG), and platelet aggregation together with basic coagulation testing. Three women had elevated bleeding score with von Willebrand disease diagnosis confirmed in one case and eleven cases had elevated e-PBAC. We report normal ranges for TEG and platelet aggregation in women during the first half of the menstrual cycle and show 23.4% of apparently normal women may have general or heavy menstrual bleeding. This is a prelude to a larger study to determine the validity of bleeding assessment tools in screening for MBDs in women.

Characterization of multiple platelet activation pathways in patients with bleeding as a high-throughput screening option: use of 96-well Optimul assay

AbstractUp to 1% of the population have mild bleeding disorders, but these remain poorly characterized, particularly with regard to the roles of platelets. We have compared the usefulness of Optimul, a 96-well plate-based assay of 7 distinct pathways of platelet activation to characterize inherited platelet defects in comparison with light transmission aggregometry (LTA). Using Optimul and LTA, concentration-response curves were generated for arachidonic acid, ADP, collagen, epinephrine, Thrombin receptor activating-peptide, U46619, and ristocetin in samples from (1) healthy volunteers (n = 50), (2) healthy volunteers treated with antiplatelet agents in vitro (n = 10), and (3) patients with bleeding of unknown origin (n = 65). The assays gave concordant results in 82% of cases (κ = 0.62, P < .0001). Normal platelet function results were particularly predictive (sensitivity, 94%; negative predictive value, 91%), whereas a positive result was not always substantiated by LTA (specificity, 67%; positive predictive value, 77%). The Optimul assay was significantly more sensitive at characterizing defects in the thromboxane pathway, which presented with normal responses with LTA. The Optimul assay is sensitive to mild platelet defects, could be used as a rapid screening assay in patients presenting with bleeding symptoms, and detects changes in platelet function more readily than LTA. This trial was registered at www.isrctn.org as #ISRCTN 77951167.

Evaluation of Pediatric Bleeding Questionnaire in Turkish Children With Von Willebrand Disease and Platelet Function Disorders

The diagnosis of mild bleeding disorders is not easy as most of the "healthy" individuals also report bleeding symptoms. In order to get a precise bleeding history, Pediatric Bleeding Questionnaire (PBQ) has been developed. In our study, Turkish children diagnosed with Von Willebrand disease (VWD), platelet function defect (PFD), and healthy children without any symptoms (control group 1) and healthy children with symptoms but found hemostatically normal (control group 2) were analyzed with PBQ. The cut off level for "positive bleeding score" was found to be ≥2 (area under the curve [AUC]: 0.785, 95% confidence interval [CI]: 0.718-0.852). The sensitivity, specificity, positive predictive value, and negative predictive value of PBQ to define VWD versus control group 1 was 100%, 97.4%, 96.4%, and 100%; VWD versus control group 2 was 100%, 53.1%, 64.3%, and 100%; PFD versus control group 1 was 93.3%, 53.1%, 73.7%, and 85%; and PFD versus control group 2 was 93.3%, 53.1%, 73.7%, and 85%, respectively.

The cost-effectiveness of ulipristal acetate tablets in treating patients with moderate to severe symptoms of uterine fibroids

ObjectivesUlipristal acetate is a selective progesterone receptor modulator that has been demonstrated to be an effective 3-month pre-operative treatment for moderate to severe symptoms of uterine fibroids in adult women of reproductive age. The aim of this analysis was to assess the cost-effectiveness of 5mg ulipristal as an add-on therapy to standard pre-surgical observation and treatment in Hungary. Study designA Markov model was developed using a 10-year time horizon. Ulipristal was compared with pre-surgical observation and immediate hysterectomy. The model comprised the following mutually exclusive health states: mild, moderate, severe, or persistent severe excessive bleeding disorder; myomectomy; post-myomectomy with mildly to moderately excessive bleeding disorder; post-myomectomy with severely excessive bleeding disorder; hysterectomy; post-hysterectomy; post-menopause; and death. Transition probabilities and utility values were obtained from clinical trials and the scientific literature. Resource utilisation and unit costs were derived from a consensus panel of clinical experts, National Health Insurance Fund tariffs, and publications. ResultsAdding a 3-month course of ulipristal to pre-operative observation was predicted to achieve an additional 0.021 quality-adjusted life years (QALYs) at an estimated incremental cost of €397, which would result in an incremental cost of €19,200/QALY. When 3 months of ulipristal therapy was compared with immediate hysterectomy, the incremental cost-effectiveness ratio was reduced to €3575/QALY. The results were most sensitive to the utility value of the post-hysterectomy health state but responsive to changes in other model parameters. ConclusionsThe results of this analysis suggest that adding ulipristal treatment to standard pre-surgical therapy represents a good value for money in Hungary. The inclusion of societal benefits may considerably reduce the cost-effectiveness ratio.

The Accuracy Of a Parent-Administered Bleeding Assessment Tool In a Pediatric Hematology Clinic

BackgroundThe introduction of bleeding assessment tools (BATs) to quantify the presence and severity of commonly reported bleeding symptoms has received increased interest over the past decade. Bleeding scores, along with laboratory data and family history, can assist the clinician in the assessment of a suspected mild bleeding disorder (MBD). While clinician-administered BATs have been utilized frequently, implementation and validation of the accuracy of a self-report or parent-proxy BAT have yet to be investigated. The primary objective of this study was to determine the accuracy of a parent-administered BAT by measuring the level of agreement between parent and clinician responses to the Condensed MCMDM-1VWD Bleeding Questionnaire. MethodsOur study population included children aged 0-19 years presenting to the hematology clinic at Nationwide Children's Hospital (Columbus, OH) for initial evaluation of a suspected MBD or for follow-up evaluation of a previously diagnosed MBD. At the time of the visit, the parent/caregiver completed a short demographic survey and a modified version (targeted for a 6th grade comprehension level) of the Condensed MCMDM-1VWD Bleeding Questionnaire. The treating provider also completed the BAT by interviewing the patient and his/her caregiver; clinicians were blinded to the results of the parent BAT. Both the parent and clinician versions of the BAT were scored and analyzed in the same manner for ease of comparison. We calculated the percentage of agreement and weighted kappa statistic for individual bleeding symptoms as well as the mean across all questionnaire items. We also examined the agreement between caregiver and clinician responses in regards to patient age, gender, diagnosis (new versus follow-up patient), and parent education level. ResultsTo date, we have enrolled 55 eligible patients. The overall mean bleeding score (BS) as calculated from the parent-report BAT was 5.98 (range: -1-25), while the mean BS for the clinician-report BAT was 3.87 (range: 0-16). The mean percentage of agreement between parents and clinicians across all items was 76% (range: 58-98%). The mean weighted kappa statistic was 0.31 (range: -0.04-0.79), representing fair agreement (based on Landis and Koch criteria); the mean Gwet's AC1 (an alternative kappa statistic) was 0.72 (range: 0.48-0.98), representing substantial agreement. Overall, 20% of parent and clinician total bleeding scores matched exactly, and an additional 42% of parent and clinician scores varied by only one to two points. 82% of the study population had an abnormal total bleeding score (defined as ≥2) when rated by parents and 78% had an abnormal total score when rated by clinicians (82% agreement, kappa = 0.43, Gwet's AC1 = 0.73). Tests for equal kappa coefficients did not show significant differences in agreement between parents and clinicians when compared by patient gender, age, diagnosis, or parent education level. DiscussionTo our knowledge, the results of a patient and/or parent-administered BAT score have not been studied to determine their accuracy and feasibility of use as a screening method for patients with a suspected MBD. While parents tended to over-report bleeding as compared to clinicians, overall, parent and clinician bleeding scores were similar in our study, and these results lend support for the potential use of a modified proxy-report BAT in a clinic setting. Additional research into the construct of the parent-administered BAT is needed to further improve the accuracy of parent-reported bleeding symptoms. Disclosures:Lang:OSUCOM Bennett Medical Student Research Scholarship: Research Funding; ASH HONORS Award: Research Funding.

Hemorrhagic Complications With Adenotonsillectomy In Children and Young Adults With Bleeding Disorders

Hemorrhagic complications remain a challenge with surgical procedures in patients with bleeding disorders. Tonsillectomy and adenoidectomy are some of the most common surgical procedures performed in pediatric patients. Adequate hemostasis in patients with bleeding disorders is centered on comprehensive hemostatic support and dexterous surgical technique. To assess our institutional experience with children and young adults with bleeding disorders that underwent tonsillectomy and/or adenoidectomy we performed a retrospective chart review of all such patients (age< 25 years) over duration of 20 years from July 1992 to July 2012. Nineteen patients were identified. The mean age was 10.2 years (Range 2.5 – 23.2 years) with 13 females and 6 males. The cohort included 2 patients with platelet disorders, 5 patients with von Willebrand disease and 12 patients with factor deficiencies (see table 1). Sixteen patients (84%) underwent tonsillectomy and adenoidectomy, while 3 patients (16%) underwent tonsillectomy only. Pre-operative treatment in the form of coagulation factor infusion (with a goal of 100% factor levels prior to surgery) or DDAVP was given to 16 patients (84%). Nine patients (47%) received anti-fibrinolytic agent, aminocaproic acid, starting pre-operatively for an average of 15.5 days (Range 10 – 36 days) post-operatively. Six patients (32%) received aminocaproic acid only post-operatively for an average of 12 days (Range 7-14 days). One patient received Tranexamic acid for 19 days. Intraoperative hemostasis was achieved by electrocautery in 16 patients (84%) and coblation technique in 2 patients (10%). Surgical hemostasis technique for 1 patient was undocumented, however this patient did not have any bleeding complications subsequently. Ten patients (53%) experienced post-operative hemorrhage including 2 patients (10%) with early (<24 hours) bleeding and 8 patients (42%) with delayed (>24 hours) bleeding from surgical site. Bleeding resolved spontaneously in 2 patients while 8 patients (42%) required interventions such as cauterization (4 patients), extended aminocaproic acid dosing (4 patients), DDAVP (1 patient), DDAVP and tranexamic acid (1 patient), recombinant factor VII (1 patient), Humate-P® (1 patient), Factor VIII infusion (1 patient) and Factor IX infusion (1 patient). Three patients (30% of bleeding patients) required transfusions including 1 patient that received platelet transfusions, 1 patient received PRBCs and another patient received FFP. Recurrent bleeding was noted in 3 patients and the rate was significantly higher in older patients amongst those with bleeding complications (p=0.0189).Table 1Age (years, months)GenderDiagnosisSeverity of diseasePost-operative bleeding (Early ≤ 24 hours, Delayed >24 hours)Recurrent bleeding14,5MEssential ThrombocythemiaModerateEarlyYes13,6MFactor VII deficiencyMildDelayedNo6,7FFactor VII deficiencyMildDelayedNo7,6FFactor VII deficiencyMildNo-11,2FFactor XI deficiencyMildEarlyNo8,4MHemophilia ASevereDelayedNo9,4FHemophilia A carrierMildDelayedNo15,2FHemophilia A carrierMildNo-5,0MHemophilia BMildNo-23,2MHemophilia BMildDelayedYes6,1FHemophilia B carrierMildNo-6,8FHemophilia B carrierMildNo-15,2FHemophilia B carrierMildNo-11,4FMay-Hegglin anomalyModerateDelayedNo4,0FType 1 von WillebrandMildDelayedNo13,5FType 2A von WillebrandModerateDelayedYes2,5MType 2A von WillebrandModerateNo-9,9FType 2B von WillebrandModerateNo9,1FType III von WillebrandSevereNo-The rate of bleeding complications in pediatric patients with mild bleeding disorders undergoing adenotonsillectomy has been reported to be similar to that of normal population. In our cohort, delayed bleeding was more common than early bleeding consistent with current literature. We observed a higher rate of bleeding complications (53%) than reported in literature despite aggressive hemostatic support and adequate surgical techniques; however, our sample size was limited. Although there was no association between delayed hemorrhage and age, recurrent bleeding was associated with older age. We conclude that patients with bleeding disorders undergoing adenotonsillectomy are at a higher risk of bleeding and require close monitoring with hemostatic support for a prolonged period of time in post-operative period. Disclosures:No relevant conflicts of interest to declare.

The Intracellular Cargo Receptor ERGIC-53 Is Required for the Production of Infectious Arenavirus, Coronavirus, and Filovirus Particles

SummaryArenaviruses and hantaviruses cause severe human disease. Little is known regarding host proteins required for their propagation. We identified human proteins that interact with the glycoproteins (GPs) of a prototypic arenavirus and hantavirus and show that the lectin endoplasmic reticulum (ER)-Golgi intermediate compartment 53 kDa protein (ERGIC-53), a cargo receptor required for glycoprotein trafficking within the early exocytic pathway, associates with arenavirus, hantavirus, coronavirus, orthomyxovirus, and filovirus GPs. ERGIC-53 binds to arenavirus GPs through a lectin-independent mechanism, traffics to arenavirus budding sites, and is incorporated into virions. ERGIC-53 is required for arenavirus, coronavirus, and filovirus propagation; in its absence, GP-containing virus particles form but are noninfectious, due in part to their inability to attach to host cells. Thus, we have identified a class of pathogen-derived ERGIC-53 ligands, a lectin-independent basis for their association with ERGIC-53, and a role for ERGIC-53 in the propagation of several highly pathogenic RNA virus families.

An adenine insertion in exon 6 of human GP6 generates a truncated protein associated with a bleeding disorder in four Chilean families

Glycoprotein VI (GPVI), 60-65kDa, is a major collagen receptor on platelet membranes involved in adhesive and signaling responses. Mice lacking GPVI have impaired platelet response to collagen and defective primary adhesion and subsequent thrombus formation. Complete or partial deficiency of GPVI in humans is a rare condition presenting as a mild bleeding disorder. The defect in most of the reported patients is acquired and associated with other diseases. To date, only two patients have been characterized at the molecular level who carry different compound heterozygous mutations in the GP6 gene. To report four unrelated patients from non-consanguineous families who presented with mucocutaneous bleeding. They had absent platelet aggregation and (14) C-5-HT secretion with collagen, convulxin and collagen-related peptide. Flow cytometry and immunofluorescence-confocal microscopy showed an absence of GPVI in non-permeabilized platelets. All the patients had an adenine insertion in exon 6 (c.711_712insA), changing the reading frame and generating a premature 'stop codon' in site 242 of the protein. The mutation predicts the synthesis of the truncated protein before the trans-membrane domain, corresponding to a band of ≈49kDa observed in western blots and in permeabilized platelets by immunofluorescence. Platelet mRNA from all the patients was sequenced and contained the corresponding adenine insertion. Heterozygous relatives had no pathological bleeding, normal response to collagen and convulxin and intermediate membrane expression of GPVI. The identification of four unrelated homozygous patients with an identical defect suggests that inherited GPVI deficiency is more frequent than previously suspected, at least in Chile.

Phenotyping and Genotyping of Platelet Disorders

Investigation of patients with mild bleeding disorders might provide novel information on the regulation and role of platelet proteins. It might even identify new targets for prevention of thrombosis. However, gene mutations require phenotypic support to assign causation, according to findings from the observational study, Genotyping and Platelet Phenotyping [GAPP; ISRCTN77951167; UKCRN ID 9858]. This article presents results to date from the study.

THE ROLE OF BLEEDING HISTORY AND CLINICAL MARKERS FOR THE CORRECT DIAGNOSIS OF VWD

Quantification of the bleeding severity by use of bleeding assessment tools (BAT) and bleeding score (BS) has been consistently shown to improve the clinical diagnosis of von Willebrand disease (VWD) while helping researchers establish phenotype/genotype correlations. Subjects with a BS equal or higher than 3 may be consider having a bleeding tendency, and should be referred for a laboratory investigation, particularly for VWD. In the diagnosis of type 1 VWD, the use of the BS has been shown to be highly specific (>95%) with reported sensitivities ranging from 40 to 100%. The BS is related to all available measurements of von Willebrand factor activity, including the PFA-100 closure time. Therefore, in clinical practice the use of BAT should always be the first step to standardize the assessment of patients with suspected VWD. The use of the recent ISTH consensus BAT is suggested to harmonize the collection of bleeding symptoms in patients with a suspected or confirmed hemostatic disorder, particularly VWD. The ISTH BAT is also coupled with a Web-based repository of bleeding symptoms, therefore providing an integrated framework for collaboration in the field of clinical evaluation of VWD and mild bleeding disorders.