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von Willebrand disease (VWD) type 2 is caused by qualitative abnormalities of von Willebrand factor (VWF). This study aimed to determine the genotypic and phenotypic characterizations of a large VWD type 2 cohort from Milan. We included 321 patients (54% female) within 148 unrelated families from 1995 to 2021. Patients were fully characterized using laboratory phenotypic tests, and the genotypic diagnosis was confirmed by target genetic analysis using Sanger sequencing. Patients were diagnosed with type 2A (n = 98; 48 families), 2B (n = 85; 38 families), 2M (n = 112; 50 families), or 2N (n = 26; 12 families). Eighty-two unique VWF variants, including 8 novel variants, were found. The potential pathogenic effect of novel variants was assessed by in silico analysis. Most patients were heterozygous for a single variant (n = 259; 81%), whereas 37 cases (11%) had 2 variants (4 homozygous, 9 in trans, and 24 in cis). Twenty-five patients (8%) had ≥3 variants, mainly as a result of gene conversions. Among the 82 distinct variants identified, 5 different types, including missense (n = 64), gene conversion (n = 10), synonymous (n = 1), deletion (n = 4), and splice (n = 3), were observed. The results from this large cohort showed that VWD type 2 is invariably due to variants that do not prevent the synthesis of the protein, and a vast majority of patients (88%) had missense variants. Given the complexity of type 2 diagnosis and the necessity of performing several phenotypic tests, genetic analysis for patients suspected of having type 2 is beneficial to establish the correct diagnosis.

Background and objective Recombinant factor XIII (rFXIII) at the recommended dosage of 35 IU/kg every 4 weeks is currently used for prophylaxis of bleeding in patients affected by FXIII deficiency. The aim of this study was to describe the population pharmacokinetics of rFXIII in patients with FXIII deficiency being treated with rFXIII in real-life and to assess, using Monte Carlo simulations, the attainment of defined FXIII concentration thresholds associated with prevention of the risk of bleeding over time. Methods A nonlinear mixed-effects model approach was used for population analysis. Monte Carlo simulations were used to generate 10,000 FXIII concentration-time profiles associated with incremental doses of 25, 30, 35, 40, 45 and 50 IU/kg of rFXIII. The probability of target attainment (PTA) of FXIII concentrations at thresholds of > 0.05, > 0.10 and > 0.15 IU/mL were calculated weekly, from days 7 to 49. Results A total of 18 patients provided 99 FXIII concentrations; most patients (77.8%, 14/18) had severe FXIII deficiency. A two-compartment pharmacokinetic model with linear elimination from the central compartment best described rFXIII data. No covariates were associated with rFXIII disposition. Pharmacokinetic parameter estimates were 0.16 mL/h/kg for clearance, 57.35 mL/kg for volume of distribution at steady-state, and 11.72 days for elimination half-life. The standard 35 IU/kg dose resulted in PTAs of the pharmacodynamic thresholds of FXIII concentrations of > 0.05, > 0.10 and > 0.15 IU/mL at day 28 that were equal to 89.9%, 68.9% and 47.8%, respectively. Conclusions Intensive FXIII monitoring from day 14, and/or shortening the dosing interval between rFXIII administrations, should be considered to minimise the risk of bleeding.

B-cell lymphoproliferative diseases may be associated with acquired hemostasis disorders, such as acquired hemophilia A (AHA) caused by autoantibodies that neutralize factor VIII activity, and δ-storage pool deficiency, an abnormality of platelet function due to defective dense granules and impaired secretion. We describe the case of a 67-year-old man in whom these two acquired bleeding disorders were concomitantly present as the first clinical manifestation of an indolent non-Hodgkin lymphoma. Immunosuppressive therapy with prednisone was initially started to eradicate anti-FVIII antibodies, subsequently boosted with cyclophosphamide and rituximab, these medications being also chosen to treat the associated indolent lymphoma. Bleeding symptoms were first tackled with limited benefit by using rFVIIa and then rescued using recombinant porcine FVIII. After a 6 month's follow-up lymphoma and AHA were in remission and platelet function was improved. This case underlines the need of multiple and complex diagnostic and therapeutic approaches to rare acquired bleeding disorders associated with lymphoproliferative diseases.

Haemophilia A and B are X-linked hemorrhagic disorders caused by gene variants in the F8 and F9 genes. Due to recessive inheritance, males are affected, while female carriers are usually asymptomatic with a wide range of factor VIII (FVIII) or IX (FIX) levels. Bleeding tendency in female carriers is extremely variable and may be associated with low clotting factor levels. This could be explained by F8 or F9 genetic variations, numerical or structural X chromosomal anomalies, or epigenetic variations such as irregular X chromosome inactivation (XCI). The aim of the study was to determine whether low FVIII or FIX coagulant activity in haemophilia carriers could be related to XCI and bleeding symptoms. HUMARA assay was performed on 73 symptomatic carriers with low clotting activity ≤50 IU/dL. Bleeding Assessment Tool (BAT) from the International Society on Thrombosis and Haemostasis (ISTH) was used to describe symptoms in the cohort of carriers. In 97% of haemophilia carriers, a specific gene variant in heterozygous state was found, which alone could not justify their low FVIII or FIX levels (≤50 IU/dL). A statistical association between XCI pattern and FVIII and FIX levels was observed. Moreover, female carriers with low coagulant activity (≤20 IU/dL) and high degree of XCI ( ≥ 80:20) had a higher ISTH-BAT score than the carriers with the opposite conditions (>20 IU/dL and

Gastrointestinal (GI) bleeding is distinctive of severe von Willebrand disease (VWD), generally arising in older patients; in most cases, blood transfusion and hospitalization are required. The presence of arteriovenous malformations is often described when endoscopic examinations are performed. Patients with congenital type 3, 2A, and 2B are those most frequently affected by this symptom, possibly due to the loss of high-molecular-weight multimers of von Willebrand factor (VWF). GI bleeding can also occur in patients affected by acquired von Willebrand syndrome. Endoscopic examination of the GI tract is necessary to exclude ulcers and polyps or cancer as possible causes of GI bleeding. In congenital VWD, prophylaxis with VWF/factor VIII concentrates is generally started after GI-bleeding events, but this therapy is not always successful. Iron supplementation must be prescribed to avoid chronic iron deficiency. Possible rescue therapies (high-dose statins, octreotide, thalidomide, lenalidomide, and tamoxifen) were described in a few case reports and series; however, surgery may be necessary in emergency situations or if medical treatment fails to stop bleeding. In this article, we present several clinical cases that highlight the clinical challenges of these patients and possible strategies for their long-term management.

INTRODUCTION: Emicizumab is a humanised bispecific monoclonal antibody, which replaces the function of factor VIII (FVIII) by bridging activated factor IX and factor X. Emicizumab is approved for prophylaxis of patients with Hemophilia A (HA), both with and without inhibitors. Real-world data on the efficacy and safety of emicizumab were recently reported from a few hemophilia treatment centers, but more data are needed to assess the efficacy and safety of emicizumab in comparison to standard prophylactic treatment. OBJECTIVE: To evaluate the safety and efficacy of emicizumab prophylaxis in a single cohort of patients with HA, with and without inhibitors. METHODS: We performed an observational prospective study including patients affected with HA, with and without inhibitors, switched to emicizumab prophylaxis in the post-marketing era. Data regarding inhibitor status, Annualized Bleeding Rate (ABR), cause of bleeding, type and location of bleeds, Emicizumab Plasmatic Concentration [Emi] and activated partial thromboplastin time (aPTT) were collected for each patient. Hemophilia Joint Health Scores (HJHS) and General Health Visual Analogue Scale (GH-VAS) were collected by trained physiotherapists before switching to emicizumab and 12 months after treatment start. RESULTS: A total of 22 patients, 21 with severe and 1 with moderate HA, were enrolled. Twenty patients were without inhibitor against FVIII and 2 adults with inhibitor were previously treated with bypassing agents. All patients started emicizumab prophylaxis with a loading dose of 3 mg/kg once weekly for 4 weeks, followed by a maintenance dosage of 1.5 mg/kg weekly. Within the children cohort, 3 were Previously Untreated Patients (PUPs) and 2 were previously treated with FVIII without developing inhibitor. The ABR showed a reduction of 74% in the entire cohort, as reported in Table 1. When stratifying for age groups, the ABR reduction was 70% for adults and 100% for children. Within the adults, the zero-bleeding patients increased from 2 to 11 patients (from 12 to 64%, respectively). In the adult cohort, 6 patients experienced 11 bleeding events over a mean follow-up of 300 days. Five out of 11 events were experienced in 6 months by a single patient who developed anti-drug antibodies (ADA) against emicizumab around the 5 th week ([Emi] 31.7 ug/ml). The prophylaxis with emicizumab was interrupted due to the treatment failure, which occurred despite spontaneous ADA clearance. Another patient developed ADA around the 9 th week ([Emi] 28.3 ug/ml), but without associated bleedings in up to 14 weeks of follow-up (minimum [Emi] 17 ug/ml). Of the remaining 5 adults who experienced bleedings during emicizumab prophylaxis, one patient developed spontaneous soft tissue bleeding, another one developed a spontaneous hemarthrosis in his target joint and the remaining 3 patients experienced post-traumatic joint bleedings, 2 out of 3 bleedings were in target joints. The analysis of the number of total joint bleedings before and after switching stratified for spontaneous and post-traumatic, revealed a reduction in target joint bleedings of 73% and a reduction of spontaneous and post-traumatic bleeding of 80% and 43%, respectively. All events were managed in outpatient clinic and required only a single infusion of FVIII concentrate. The plasmatic concentrations of emicizumab at steady state were within previous reported normal range for all patients, with exception of the two patients who developed ADA. Interestingly, steady state concentration was higher in children than in adults (median [Emi] 64.9 ug/ml and 49.85, respectively). The HJHS and GH-VAS scores at baseline and after 12 months of emicizumab prophylaxis available in 6 adults showed improvement in joint health and self-perceived global health, as shown in Figures 2 and 3. No thrombotic events were reported in the entire cohort. DISCUSSION: We report our Milan single center experience on the use of emicizumab prophylaxis in children and adults with HA, with and without inhibitors. Our experience shows a good efficacy of emicizumab both in children and adults, with few post-traumatic bleedings occurring mainly in target joints of adult patients. In addition, physician's and self-assessed scores revealed an improvement of patient's joint health after 12 months of emicizumab prophylaxis. Figure 1 Figure 1. Disclosures Peyvandi: Roche: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; Sobi: Consultancy, Honoraria; Sanofi: Consultancy, Honoraria.

Introduction Emicizumab is a recombinant, humanized, bispecific antibody restoring the function of missing activated factor VIII (FVIII) by bridging activated FIX (FIXa) and zymogen factor X (FX), medicating the activation of FX. Emicizumab is approved in several countries, at the doses of 1.5 mg/kg once weekly, 3 mg/kg every 2 weeks or 6 mg/kg every 4 weeks, for the prophylaxis of bleeding episodes in patients with hemophilia A with and without inhibitors. The drug has shown a good efficacy either during registration studies as well as in real-world experiences and was well tolerated without significant side effects. The development of neutralizing anti-emicizumab antibodies has been reported in very few cases which frequently required the switch to other products due to inefficacy of the prophylaxis. Patients maintaining a plasma concentration range of the drug within 30-80 ug/ml did not show significant bleeds. However, real life experiences bring the need of personalization of the drug dose. A recent case series presented at ISTH 2021 from Malaysian authors evaluated the efficacy of a dose of emicizumab between 1.7 and 1.9 mg/kg every 4 weeks, showing that even at a lower dose than that approved could be effective for the prevention of bleeding events. Here we report the case of an adult patient with moderate hemophilia A with inhibitor who developed an anti-emicizumab antibody which reduced the concentration of the drug by 50%. Despite that the patient did not report bleeding events in a follow-up period of 18 weeks. Treatment with emicizumab requires further evaluation to understand the best dose for the prevention of bleeding. Case report A 74 years old patient with moderate hemophilia A (FVIII 1-3%) followed at our Center had history of high-titer inhibitor (maximum titer 20 BU). The patient was treated on-demand with plasma-derived FVIII concentrates, when, in Jul 2000, he developed a neutralizing anti-FVIII antibody requiring treatment with activated prothrombin complex concentrates (Feiba). In Nov 2020 the patient was hospitalized for traumatic brain hemorrhage treated with plasma-derived FVIII (inhibitor titer < 5 BU) and subsequently, for the recurrence of inhibitor, with activated prothrombin complex concentrates. In Feb 2021 the patient started prophylaxis with emicizumab at the initial dose of 3 mg/kg once weekly (loading dose), followed by a maintenance dose of 1.5 mg/kg. The patient underwent periodic blood withdrawal for monitoring drug plasma concentration. In Apr 2021 (week 10) drug concentration showed a slight decrease from initial levels, from 39.1 ug/ml (week 5) to 28.3 (week 10) and a weak positivity for an anti-emicizumab antibody was detected. At the following test (week 15) positivity for the anti-emicizumab antibody was confirmed, witnessed by the consistent reduction in drug plasma concentration up to 20.9 ug/ml. During the following weeks, until week 22, drug plasma concentrations were stable (range 17.0-19.4 ug/ml) and positivity for anti-emicizumab antibody remained, as shown in the table. The results of partial Thromboplastin Time (PTT) were consistent with the drug plasma concentrations during the observation period, in which the patient did not developed any bleeding event. Conclusion This case report may corroborate the hypothesis of the efficacy of a reduced dose of emicizumab in patients with hemophilia A. Close laboratory monitoring in patients in prophylaxis with emicizumab is warranted for the evaluation of drug plasma concentration and the prompt detection of anti-drug antibodies, particularly if patient show a reduced therapeutic efficacy. However, in the absence of bleeding events, positivity for anti-emicizumab antibodies should not bring to sudden drug discontinuation. Indeed, in the view of the above, a lower drug plasma concentration than standard might be effective in the prevention of bleeding. 1. Tang ASO et al. July 2021. Efficacy of Reduced-dose Emicizumab in Haemophilia A with Inhibitors: Real World Experience in East Malaysia. ISTH 2021. Figure 1 Figure 1. Disclosures Peyvandi: Takeda: Consultancy, Honoraria; Sobi: Consultancy, Honoraria; Sanofi: Consultancy, Honoraria; Roche: Consultancy, Honoraria.

Introduction Bleeding manifestations among patients with rare bleeding disorders (RBDs) vary significantly between disorders and patients, even when affected with the same disorder. In response to the challenge represented by the clinical assessment of the presence and severity of bleeding symptoms, a number of bleeding score systems (BSSs) or bleeding assessment tools (BATs) were developed. The majority of these were specifically developed for patients with more common bleeding disorders than RBDs. Few RBDs patients were evaluated with these tools and without conclusive results. Methods A new BSS was developed using data retrieved from a large group of patients with RBDs enrolled in the EN-RBD database and from healthy subjects. These data included previous bleeding symptoms, frequency, spontaneity, extent, localization, and relationship to prophylaxis and acute treatment. The predictive power of this BSS was also compared with the ISTH-BAT and examined for the severity of RBDs based on coagulant factor activity. Results This BSS was able to differentiate patients with RBDs from healthy individuals with a bleeding score value of 1.5 having the highest sum of sensitivity (67.1%) and specificity (73.8%) in discriminating patients with RBD from those without. An easy-to-use calculation was also developed to assess the probability of having a RBD. Its comparison with the ISTH-BAT confirmed its utility. Finally, in RBDs patients, there was a significant negative correlation between BS and coagulant factor activity level, which was strongest for fibrinogen and FXIII deficiencies. Conclusion The use of this quantitative method may represent a valuable support tool to clinicians.

Background: Major hemorrhages in newborns can be caused by several conditions, and knowledge of the differential diagnosis is essential in order to ensure prompt recognition and appropriate treatment. Case Report: We describe the case of a male newborn experiencing recurrent hemorrhages from the first days of life. Laboratory findings showed normal platelet count, hepatic function, and C-reactive protein. Coagulation tests detected an isolated prothrombin time (PT) prolongation and severe factor VII (FVII) deficiency. Conclusion: Inherited FVII deficiency is a rare autosomal recessive bleeding disorder. Clinical presentation is heterogeneous, and bleeding severity is not directly related to FVII levels. Acute bleeding episodes can be treated with human plasma-derived FVII (pdFVII) or recombinant activated FVII (rFVIIa). In case of severe deficiency, prophylaxis must be evaluated. Awareness of this condition is crucial in order to establish prompt diagnosis and treatment.

UNLABELLED Essentials Plasma of factor XI-deficient patients (FXI-dp) displays enhanced fibrinolysis. We investigated the role of thrombin activatable fibrinolysis inhibitor (TAFI) in 18 FXI-dp. FXI-dp generated less activated TAFI (TAFIa) on clotting challenge and were resistant to TAFIa. TAFI activation and TAFIa resistance correlated with bleeding score and bleeding phenotype. SUMMARY Background Factor XI (FXI) deficiency, a rare disorder with unpredictable bleeding, has been associated with reduced fibrinolytic resistance as a result of abnormal fibrin density. Objective We investigated the involvement of thrombin-activatable fibrinolysis inhibitor (TAFI) in the increased lysability of FXI-deficient (FXI-def) clots and the role of thrombin. Patients/Methods Eighteen patients with FXI deficiency (1-58%) and 17 matched controls were investigated for fibrinolytic resistance to t-PA, thrombin generation, TAFI activation and response to TAFIa. Results When clotting was induced by 0.5 pm tissue factor (TF), FXI-def plasmas displayed less thrombin and TAFIa generation and shorter lysis time than controls. A 100-fold higher TF concentration (to bypass FXI) abolished the difference in thrombin generation but not in lysis time between patients and controls. Normalization of FXI levels by a FXI concentrate increased thrombin generation but had no effect on the lysis time of FXI-def plasma. Moreover, when clots were induced by purified thrombin and high concentrations of FXa inhibitor, FXI-def plasma still generated less TAFIa and displayed a shorter lysis time than controls. Finally, upon TAFIa addition, the lysis time of FXI-def plasma was prolonged significantly less than that of control plasma, suggesting a TAFIa resistance. TAFIa generation and TAFIa resistance were correlated with the bleeding score, displaying a considerable capacity to discriminate between patients with and without bleeding. Conclusions TAFI pathway impairment, largely caused by a hitherto unknown TAFIa resistance, appears to be one main cause of decreased fibrinolytic resistance in FXI deficiency and might be clinically useful for assessing the bleeding risk of FXI-def patients.

Introduction von Willebrand disease (VWD) is the most common inherited bleeding disorder. The age of bleeding onset is highly variable, also in patients with similar degree of severity. Aim The primary aim of this study was to evaluate whether baseline factor VIII (FVIII) plasma levels correlate with age at first bleeding in patients with extremely low levels of VWF:RCo (

Summary Background In individuals with borderline von Willebrand factor (VWF) plasma levels, second-level tests are required to confirm or exclude von Willebrand disease (VWD). These tests are time-consuming and expensive. Objective To assess which parameters can predict VWD diagnosis in individuals with borderline VWF levels (30–60 IU dL−1). Methods Nine hundred and fifty individuals with bleeding episodes or abnormal coagulation test results were investigated with first-level tests (blood count, prothrombin time, activated partial thromboplastin time, blood clotting factor VIII, VWF ristocetin cofactor activity [VWF:RCo], and VWF antigen), and 93 (62 females and 31 males; median age, 28 years; interquartile range 15–44) had borderline VWF:RCo levels. All underwent second-level investigations to confirm or exclude VWD. A multivariable logistic regression model was fitted with sex, age, bleeding score, family history, VWF:RCo and ABO blood group as predictors, and used to predict VWD diagnosis. Results Forty-five of the 93 individuals (48%) had VWD (84% type 1). A negative linear relationship between VWF:RCo levels and risk of VWD diagnosis was present, and was particularly evident with blood group non-O [adjusted odds ratio 7.00 (95% confidence interval [CI] 1.48–33.11) for every 5 IU dL−1 decrease in VWF:RCo]. The other variable clearly associated with VWD diagnosis was female sex (adjusted odds ratio 5.76 [95% CI 1.47–22.53]). The area under the receiver operating characteristic curve of the full logistic model was 0.89 (95% CI 0.82–0.95). Conclusions In individuals with borderline VWF, the two strongest predictors of VWD diagnosis are low VWF:RCo levels (particularly in those with blood group non-O) and female sex. This predictive model has a promising discriminative ability to identify patients with borderline VWF levels who are likely to have VWD.

Knowledge regarding the management of orthopaedic surgery in patients with rare bleeding disorders (RBDs) is limited. Retrospective data collection and analysis of 35 orthopaedic procedures (6 minor and 29 major) carried out in 22 patients with RBD between 1982 and 2013. These surgeries were performed using heterogeneous regimens of hemostatic therapy, except for seven procedures performed with no hemostatic treatment in four patients with mild factor deficiency. Of the 28 procedures carried out with hemostatic treatment, nine (32%) were performed using replacement therapy with dosages of concentrates of the deficient factor aimed to achieve perioperative plasma levels judged to be compatible with hemostasis; three (11%) using factor replacement therapy associated with fresh frozen plasma (FFP); four (14%) using recombinant activated factor VII; four (14%) using virus inactivated plasma alone; three (11%) using virus inactivated plasma associated with desmopressin; one (4%) using FFP alone; and four (14%) procedures using tranexamic acid alone. Bleeding complications occurred in 7 of 35 procedures (20%) involving five patients. Prophylaxis of venous thromboembolism was performed only in one case with no excessive bleeding, but two patients not on thromboprophylaxis developed superficial thrombophlebitis. A satisfactory control of hemostasis was achieved in most patients. In some of those characterized by mild factor deficiency (FVII, FXI) hemostatic treatment could be avoided in some instances. The control of hemostasis combined with an adequate surgical technique is needed for the successful outcome of orthopaedic surgery in RBDs that requires the involvement of specialized haemophilia centres.

Many persons with severe haemophilia reach seniority thanks to effective treatment. There is no information on health-related quality of life (HRQoL) of these patients, who had lived for many years when regular replacement therapy was unavailable. Italian patients with severe haemophilia aged ≥65 years born in the 1940s or earlier were compared with men without bleeding disorders matched for age and geography. HRQoL was assessed via generic and disease-specific questionnaires. Potential associations with concomitant illnesses, orthopaedic status, physical functioning, cognitive status and depression were evaluated. In addition, the newly adapted HRQoL questionnaire specific for elderly persons with haemophilia (Haem-A-QoL(Eldlery)) was psychometrically tested and validated. Thirty-nine patients, aged 65-78 years, were investigated, 33 with haemophilia A and six with haemophilia B, and compared to 43 controls, aged 65-79 years. Chronic blood borne viral infections, hypertension and arthropathy were more frequent in patients, whereas hypercholesterolemia and cardiovascular diseases were more frequent in controls. Psychometric characteristics of Haem-A-QoL(Elderly) showed good to excellent values for reliability and validity. HRQoL was worse in patients at EQ-VAS, WHOQOL-BREF and WHOQOL-Old. The highest impairments were found in patients by means of the haemophilia-specific Haem-A-QoL(Elderly) in such dimensions as 'physical activity & leisure', 'physical health' and 'view'. A poor orthopaedic status was negatively associated with HRQoL. Compared to age-matched controls elderly patients with haemophilia had an impaired HRQoL in association with their health status. The newly developed Haem-A-QoL(Elderly) proved to be a reliable and valid instrument for HRQoL assessment in elderly haemophilia patients.

Central nervous system (CNS) bleeding is one of the most severe and debilitating manifestations occurring in patients with rare bleeding disorders (RBDs). The aim of this study was to retrospectively collect data on patients affected with RBDs who had CNS bleeding, to establish incidence of recurrence, death rate, neurological sequences, most frequent location, type of bleeding and efficacy of treatments. Results pertained to 36 CNS bleeding episodes in 24 patients with severe deficiency except one with moderate factor VII (FVII) deficiency. Six patients (25%) experienced a recurrence and two had more than one recurrence. Seven patients (29%) had an early onset of CNS bleeding before the first 2 years of life, others (71%) later in life. In 76% of cases, CNS bleeding was spontaneous. CNS bleeding was intracerebral in 19 cases (53%), extracerebral in 10 (28%) and both intracerebral and extracerebral in two cases (6%). Neurosurgery was performed in 11 cases, in association with replacement therapy in seven cases. Seizures were noted in four patients. Residual psychomotor abnormalities were seen in two patients. No death was recorded. To prevent recurrence, 17/24 patients (71%) were put on secondary prophylaxis. In conclusion, recurrence of CNS bleeding was confirmed to be relatively frequent in patients with severe FV, FX, FVII and FXIII deficiencies. Most patients were managed with replacement therapy alone, surgery being reserved for those with worsening neurological conditions. Our results indicate that some RBDs require early prophylactic treatment to prevent CNS bleeding. Optimal dosage and frequency of treatment need further evaluation.

Summary. Free foetal DNA in maternal blood during early pregnancy is an ideal source of foetal genetic material for non-invasive prenatal diagnosis. The aim of this study was to evaluate the use of free foetal DNA analysis at early gestational age as pretest for the detection of specific Y-chromosome sequences in maternal plasma of women who are carriers of X-linked disorders, such as haemophilia. Real-time quantitative PCR analysis of maternal plasma was performed for the detection of the SRY or DYS14 sequence. A group of 208 pregnant women, at different gestational periods from 4 to 12 weeks, were tested to identify the optimal period to obtain an adequate amount of foetal DNA for prenatal diagnosis. Foetal gender was determined in 181 pregnant women sampled throughout pregnancy. Pregnancy outcome and foetal gender were confirmed using karyotyping, ultrasonography or after birth. The sensitivity, which was low between 4th and 7th week (mean 73%), increased significantly after 7+1th weeks of gestation (mean 94%). The latter sensitivity after 7+1th week of gestation is associated to a high specificity (100%), with an overall accuracy of 96% for foetal gender determination. This analysis demonstrates that foetal gender determination in maternal plasma is reliable after the 9th week of gestation and it can be used, in association with ultrasonography, for screening to determine the need for chorionic villus sampling for prenatal diagnosis of X-linked disorders, such as haemophilia.

Although rare, type 3 von Willebrand disease (VWD3) is of major interest because of its severe clinical presentation, the need for replacement therapy with von Willebrand Factor (VWF) concentrates and the risk of anti-VWF inhibitors. To better characterize the clinical and laboratory features of this rare inherited bleeding disorder, a large cohort of VWD3 patients has been enrolled into the type 3 Von Willebrand International RegistrieSInhibitor Prospective Study. 3WINTERS-IPS is a no-profit, investigators initiated, multicenter, European-Iranian (EU-IR) observational, retrospective and prospective study on patients with VWD3 diagnosis. One of the aims of 3WINTERS-IPS is to assess the efficacy and safety of VWF concentrates with or without FVIII, including the risk of anti-VWF antibodies, in a large cohort of centrally confirmed VWD3 patients. A total of 260 previously diagnosed VWD3 cases were enrolled into the study from 18-EU and 7-IR investigation sites (retrospective registries) and reassessed by 5 expert labs for phenotypic and genotypic analyses to confirm VWD3 diagnosis (central confirmation). Only 201/260 (77%) cases with centrally confirmed VWD3 diagnosis were included into the 24-month clinical observation (prospective phase) registered as NCT02460458 into Clinical-Trials.gov. All the clinical and laboratory data were reported by investigators into the database online organized by a CRO under the direct supervision of the Scientific Coordinators. Clinical results on the efficacy and safety of VWF concentrates during the first 18-month observation are currently available on 149/201 (74%) VWD3 patients (EU=62/IR=87) with the following sex (M/F) and age (Mean-SD, Median) distribution: 86/115 and 28.9-18, 27. Anti-VWF antibodies were confirmed in 16/201 (8%) VWD3: these patients are under treatment with recombinant FVIII without VWF or recombinant activated Factor VII. Being 3WINTERS-IPS a non-interventional study, the therapeutic approaches such as on demand (OD) or secondary long-term prophylaxis (SLTP) with the assigned VWF concentrates with or without FVIII (FANHDI, HAEMATE-P, WILATE, WILFACTIN) were decided by local investigators. The number of VWD3 treated OD/SLTP were 106/43 with more cases under SLTP at EU than at IR sites (28/15). Cases under OD/SLTP with bleeds were 73/106(69%) of OD and 21/43(48%) of SLTP. To compare the results of OD/SLTP groups, data obtained were divided by case number and by months to calculate the mean (range) annual bleeding rate (ABR). ABR observed so far in OD/SLTP is 4.3 (2.8-5.8)/3.1(1.4-3.8) with nose (29/28%), joint (19/24%), uterus (13/23%) bleeds being the most frequent sites. To manage (OD) or prevent (SLTP) bleeds the mean (range) consumption of VWF:RCo units of VWF concentrates per patient were 4800 (1800-15.500) and 8000 (5000-10.500) units, respectively. During follow-up VWD3 patients under OD/SLTP were exposed to 17/10 minor/major surgeries with 14.900 (9.500-22.000)/17.200 (12.800-31.000) VWF:RCo Units used per surgery. Efficacy of the different VWF concentrates was reported as good/excellent during bleeds and surgeries. No side effects related to VWF concentrates were reported by investigators: no additional anti-VWF antibodies were found after the use of VWF concentrates. Based on this interim analyses on the largest cohort of VWD3 currently under prospective observation, the frequency of spontaneous bleeds assessed by ABR seems lower than expected by the severe VWF defect of VWD3. So far, the use of SLTP seems to reduce the ABR. However, a longer prospective observation (from 2 to 5 years) with 3WINTERS-IPS-EXTENDED is required to characterize bleeding phenotype of VWD3 patients and to prepare recommendations on the appropriate use (OD/SLTP) of the VWF concentrates Disclosures Leebeek: Uniqure: Research Funding; Baxalta/Shire: Research Funding; CSL Behring: Research Funding. Peyvandi:Kedrion: Consultancy; Kedrion: Consultancy; Kedrion: Consultancy; Novo Nordisk: Speakers Bureau; Novo Nordisk: Speakers Bureau; Grifols: Speakers Bureau; Ablynx: Other: Member of Advisory Board, Speakers Bureau; Ablynx: Other: Member of Advisory Board, Speakers Bureau; Grifols: Speakers Bureau; Ablynx: Other: Member of Advisory Board, Speakers Bureau; Ablynx: Other: Member of Advisory Board, Speakers Bureau; Octapharma US: Honoraria; Roche: Speakers Bureau; Shire: Speakers Bureau; Ablynx: Other: Member of Advisory Board, Speakers Bureau; Kedrion: Consultancy; Grifols: Speakers Bureau; Kedrion: Consultancy; Novo Nordisk: Speakers Bureau; Grifols: Speakers Bureau; Grifols: Speakers Bureau; Novo Nordisk: Speakers Bureau; Roche: Speakers Bureau; Novo Nordisk: Speakers Bureau; Roche: Speakers Bureau; Roche: Speakers Bureau; Shire: Speakers Bureau; Sobi: Speakers Bureau; Roche: Speakers Bureau; Shire: Speakers Bureau; Shire: Speakers Bureau; Octapharma US: Honoraria; Sobi: Speakers Bureau; Sobi: Speakers Bureau; Shire: Speakers Bureau; Sobi: Speakers Bureau; Octapharma US: Honoraria; Octapharma US: Honoraria; Sobi: Speakers Bureau; Octapharma US: Honoraria. Eikenboom:CSL: Research Funding.

Introduction The spectrum of bleeding problems in FVII deficiency is highly variable and FVII levels and causative genetic mutations correlate poorly with the bleeding risk. Long-term prophylaxis is generally initiated in order to prevent subsequent CNS bleeding after a first event or in patients with other major/ life threatening/ frequent bleeding symptoms as gastrointestinal bleeding or hemarthrosis. However few data are available in the literature regarding FVII prophylaxis and clinical decisions cannot be based on evidence. Aims We report the data available in the literature on FVII prophylaxis and our personal experience regarding three patients affected by severe FVII deficiency. Methods Specific papers on long-term prophylaxis in severe FVII deficiency were identified using the database, PUBMED. Results The most frequent indications for long-term prophylaxis were CNS bleeding (58%), hemartrosis (15%) and GI bleeding (9%). Patients were treated with various dosages and frequency. Prophylactic treatment with 10-30U/kg (pdFVII) or 20-30mcg/kg (rFVIIa) twice or three times/weeks was described to be effective. Conclusions In the literature and in our experience, prophylaxis can be considered in patients with severe FVII deficiency and severe bleeding phenotype. A dose of 10-30U/kg (pdFVII) or 20-30 microg/kg (rFVIIa) twice or three times/week is usually administrated, but dose and frequency can be tailored based on the clinical follow-up of the patients. Since hemarthrosis is a frequent manifestation, a suggestion to improve the outcomes of patients with severe FVII deficiency is to monitor joint condition in order to identify early arthropathy that could be another indication to start secondary prophylaxis.

Besides its essential role in hemostasis, there is growing evidence that von Willebrand factor (VWF) has an additional antitumor effect. To elucidate the clinical significance of this biological activity we conducted a retrospective study on cancers among Italian patients with von Willebrand disease (VWD) on behalf of the Italian Association of Haemophilia Centres (AICE). A questionnaire to collect demographic, clinical, and treatment data of VWD patients with cancer was sent to all the 54 Italian Haemophilia Treatment Centres (HTCs) members of AICE. Overall, 18 HTCs (33%) provided information on 92 VWD patients (61 alive and 31 deceased) with 106 cancers collected during the period 1981 to 2014. Of them, 19 (18%) were hematological cancers and 87 (82%) were solid cancers. A total of 61% of patients had type 1, 36% type 2 (12% type 2A, 14% type 2B, 9% type 2M, and 1% type 2N), and 3% type 3 VWD: this distribution was significantly different from that observed in the whole VWD population (79% type 1, 16% type 2 [8% type 2A, 4% type 2B, 2% type 2M, 2% type 2N], and 5% type 3; type 2 vs. non-type 2: p

Inherited deficiencies of plasma proteins involved in blood coagulation generally lead to lifelong bleeding disorders. Rare bleeding disorders (RBDs), discussed in this chapter, represent 3–5 % of all the inherited coagulation deficiencies, with prevalence ranging from approximately 1:500,000 to 1:2,000,000 in the general population. Patients affected by bleeding disorders present a wide spectrum of clinical symptoms that vary from a mild or moderate bleeding tendency to significant episodes. Women with inherited bleeding disorders are particularly disadvantaged since, in addition to suffering from general bleeding symptoms, they are also at risk of bleeding complications from regular haemostatic challenges during menstruation, pregnancy and childbirth. Moreover, such disorders pose important problems for affected women due to their reduced quality of life caused by limitations in activities and work, and alteration of their reproductive life. Management of these women is difficult because of considerable inter-individual variation. Furthermore, reliable information on clinical management is scarce, with only a few long-term prospective studies of large cohorts providing evidence to guide diagnosis and treatment.

Summary Thrombotic microangiopathies (TMAs) are rare but serious complications of bone marrow transplantation (BMT). Clinical manifestations are similar to those of thrombotic thrombocytopenic purpura (TTP), but prognosis is generally poorer despite plasma exchange. The enzymatic activity of the plasma metalloprotease ADAMTS13, which cleaves ultralarge thrombogenic multimers of von Willebrand factor (VWF) derived from activated endothelial cells, is very low or undetectable in patients with classic TTP, and protease deficiency is thought to play a mechanistic role in the formation of platelet thrombi in the microcirculation. This is the first prospective study to evaluate the incidence of TMA in 46 consecutively recruited patients undergoing autologous or allogeneic BMT and explore in parallel the behaviour of ADAMTS13, VWF antigen and VWF multimer size. The incidence of post-BMT TMA was 6% (three of 46); all cases occurred after allogeneic BMT. Compared with baseline values plasma ADAMTS13 activity was significantly reduced in patients undergoing BMT, particularly after the conditioning regimen (mean values: 50 ± 22 vs. 77 ± 32%; P

A 91-year-old woman affected with acquired Von Willebrand (VW) syndrome and intestinal angiodysplasias presented with severe gastrointestinal bleeding (hemoglobin 5 g/dl). Despite replacement therapy with VW factor/factor VIII concentrate qid, bleeding did not stop (eleven packed red blood cell units were transfused over three days). High circulating levels of anti-VW factor immunoglobulin M were documented immunoenzimatically. Heart ultrasound showed abnormalities of the mitral and aortic valves with severe flow alterations. When intravenous immunoglobulins were added to therapy, prompt clinical and laboratory responses occurred: complete cessation of bleeding, raise in hemoglobin, VW factor antigen, VW ristocetin cofactor and factor VIII levels as well as progressive reduction of the anti-VWF autoantibody levels.

Acquired von Willebrand Syndrome is a rare bleeding disorder, which arises in individuals with no personal or family history of bleeding, associated with lymphoproliferative and myeloproliferative disorders or other diseases.To develop a two-step approach assay to detect autoantibodies against VWF and to verify their prevalence in AVWS.AVWS definition: negative personal or family history of bleeding diathesis, VWF below normal range and recent history of bleeding manifestations. Twenty-three consecutive patients affected by AVWS were enrolled. An ELISA assay (first step) using recombinant VWF protein immobilized on plates and sheep/goat polyclonal anti-human IgG or IgM labelled with peroxidase was developed. A group of 40 healthy subjects was tested to calculate the floating cut point value. A confirmation assay (with addition of purified VWF vs buffer) was performed (second step).Twenty-one patients (93%) had an associated disease, two patients had idiopathic AVWS. Anti-VWF autoantibodies were detected in 9 patients (39%). Of these, eight (89%) had VWF:RCo levels10%, but none of them resulted positive using Bethesda assay (neutralizing antibodies). The confirmation test confirmed the positive results obtained with ELISA and resulted negative in those patients with negative results and in the controls.With the present two-step approach assay nine out of 23 (39%) patients affected with AVWS resulted positive for anti-VWF autoantibodies. This ELISA assay might be used as an additional confirmation tool in the diagnostic procedure in patients affected by AVWS or in the follow-up of congenital and acquired patients exposed to replacement therapy.

Patients with von Willebrand disease (VWD) may need orthopaedic surgery because of disabling chronic arthropathy due to recurrent joint bleeding. They may also require this surgery independently of their haemostasis disorder. Knowledge regarding the management of orthopaedic surgery in VWD is limited. Description of management of orthopaedic surgery in patients with VWD, based upon retrospective data collection and analysis of 32 orthopaedic procedures carried out over a period of 33 years in 23 patients was the aim of this study. Of 32 procedures, six were minor (three hand surgery, one foot surgery, two others) and 26 were major (seven joint replacements, nine arthroscopic procedures, two foot surgery, eight others). Twenty-two procedures were performed using replacement therapy with plasma-derived concentrates containing both factor VIII (FVIII) and von Willebrand factor (VWF). Two procedures in patients with acquired von Willebrand syndrome (AWVS) were performed using FVIII-VWF concentrates associated with intravenous immunoglobulins, or desmopressin plus tranexamic acid. Seven procedures were performed using desmopressin alone and one using intravenous immunoglobulins in AVWS. Bleeding complications occurred in seven procedures (22%). In one patient, an anti-VWF antibody was diagnosed after surgery. Anticoagulant prophylaxis of venous thromboembolism was implemented in four cases only and in two instances there was excessive bleeding. In conclusion, control of surgical haemostasis was achieved in most patients with VWD undergoing orthopaedic surgery. The control of haemostasis combined with an adequate surgical technique and early post-operative rehabilitation are warranted for the successful performance of orthopaedic surgery in VWD, which requires the involvement of specialized haemophilia centres.

Post-partum hemorrhage (PPH) accounts for a substantial fraction of maternal deaths in the general population. Among all women, however, those affected with rare bleeding disorders (RBDs) represent a particular group since to usual bleeding symptoms, they are likely to experience bleedings associated to obstetrical and gynaecological problems. Pregnancy and childbirth, two important stages in the life of a woman, pose a special clinical challenge in women with RBDs, since information about these issues are really scarce and limited to few case reports. These data show that all women with RBDs, except for FXI deficiency, have to be considered potentially at risk for developing PPH, therefore they should be monitored carefully during and immediately after pregnancy. The implication is that women with bleeding disorders may require prophylaxis and/or close observation for several weeks and should be followed by a multidisciplinary team including expertises such as laboratory haematologist, obstetrician-gynaecologist, anaesthesiologist, family physician, and laboratory technician.

Introduction: Elevated homocysteine (Hcy) is associated with the risk of deep vein thrombosis, pulmonary embolism, ischemic heart disease, and stroke. Several studies have suggested that hyperhomocysteinemia (HHcy) may predispose to retinal vein thrombosis (RVT) development. The aim of this study is to investigate the relationship between Hcy, C677T methylenetetrahydrofolate reductase (MTHFR) genotype, and RVT in patients compared with controls. Materials and Methods: We evaluated the Hcy plasma level of 3114 consecutive participants in 2 Italian centers during a 2-year period. Hyperhomocysteinemia was found in 99 patients and 136 healthy participants. Of the 99 patients, 20 had RVT with a high prevalence of HHcy in the RVT subgroup (20.2%). This result suggested a possible relationship between HHcy and RVT development. We investigated 105 consecutive patients with recent diagnosis of RVT, and we compared them with 226 healthy controls to evaluate whether HHcy may be a risk factor for RVT. Results: the prevalence of HHcy was higher in patients compared with controls (34.3% vs 14.2%; P < .001). The MTHFR C677T genotype was found in 69 of 105 (65.7%) patients with RVT (heterozygosity: 40 of 105 and homozygosity: 29 of 105). The control group showed the presence of MTHFR C677T genotype in 169 of 226 participants (74.8%; heterozygosity: 100 of 226 and homozygosity: 69 of 226) without difference between the 2 groups (P = .08). Conclusion: our study suggests that HHcy is a possible risk factor for RVT development, while no association was found between RVT and the C677T MTHFR genotype.

The aim of this case-control study was to analyse the prevalence of gynaecological, obstetrical and other more general bleeding symptoms in 114 women affected by various inherited bleeding disorders, who were compared with 114 apparently healthy women. Retrospective information were collected by means of two specific questionnaires, one on gynaecological and obstetrical bleeding symptoms, with special focus on the presence of menorrhagia as defined by a pictorial blood loss assessment chart (PBAC); and the other on general bleeding symptoms, whose severity was graded by means of the bleeding score (BS). Compared to normal women, the whole group of women with inherited bleeding disorders had a higher prevalence of excessive bleeding at menarche (25% vs. 5%, P0.0001) and menorrhagia (59% vs. 46%, P = 0.06). Affected women also had a higher frequency than controls of general bleeding symptoms that scored as severe by a BSor = 12 (49% vs. 0%, P0.0001). In affected women, the BS increased according to the severity of the haemostasis defect. In conclusions, the BS and the PBAC are simple tools to evaluate the severity of general bleeding symptoms and menorrhagia in women with inherited bleeding disorders. These instruments may help to identify those women for whom a therapeutic intervention is warranted.

To characterize a functional assay for circulating fibrinogen based on rotational thrombelastography. Maximum clot firmness was determined by rotational thrombelastography in normal human plasma pool, fibrinogen-deficient plasma pool, normal whole blood, and individual plasma samples from 17 patients with fibrinogen deficiency. Plasma samples spiked with varying concentrations of exogenous fibrinogen were also measured. Results were compared with enzyme-linked immunosorbent assay and Clauss assay. The impact of sample freezing and filtration and use of cytochalasin D were also investigated. Over the tested range of 0 -3 mg/ml added exogenous fibrinogen, the maximum clot firmness standard curve for determination of fibrinogen in plasma pools (n = 7) was linear (r 2 = 0.97). Maximum clot firmness was highly linearly correlated both with Clauss assay (r 2 = 0.93) and enzyme-linked immunosorbent assay (r 2 = 0.95). In unspiked plasma samples from individual patients with fibrinogen deficiency, fibrinogen was undetectable by rotational thromboelastography. By all evaluated methods, the response to spiking with fibrinogen in such samples coincided closely in patients with afibrinogenemia and hypofibrinogenemia. In dysfibrinogenemia, smaller Clauss assay responses to spiking were observed, whereas the enzyme-linked immunosorbent assay response was variable. Maximum clot firmness was the only evaluated method of fibrinogen assessment to yield consistent results across all categories of fibrinogen deficiency. These in-vitro results suggest the potential clinical utility of rotational thromboelastography as a versatile method for monitoring the response to fibrinogen concentrate among patients with fibrinogen deficiency. Clinical investigations using rotational thromboelastography after in-vivo fibrinogen administration to patients with congenital fibrinogen deficiency are warranted.

Plasminogen deficiency is a rare disease characterized by ligneous conjunctivitis and infections. We observed a 3-year-old Italian boy presenting ligneous conjunctivitis and low plasma levels of plasminogen. Twenty-three different mutations on the PLG gene have been reported to date, but mutation analysis had been troublesome for the presence of highly homologous genes. The aim of the study was to identify the underlying mutation avoiding coamplification of unwanted genetic materials using a long polymerase chain reaction strategy, instead of the previously reported subcloning methods. By this simple strategy the complete sequence analysis of PLG gene was performed, and a previously reported missense homozygous mutation (K19E) was identified.

Factor XI deficiency (FXI-Def) is associated with mild, unpredictable bleeding tendency. FXI is believed to participate in a thrombin-dependent positive feed-back that leads to the formation of a second burst of thrombin, which, in turn, inhibits fibrinolysis mainly through TAFI activation. It is conceivable, therefore, that FXI-Def leads to the formation of clots that are more susceptible to lysis. Our study was undertaken to test this hypothesis. Eighteen subjects with FXI-Def (1-58%), and 17 matched controls were studied. All assays were performed on citrate-plasma stored at -80°C. The fibrinolytic resistance to t-PA (30 ng/ml) of clots generated by 0.5 pM tissue factor was lower in samples from FXI-Def subjects than in controls (lysis time: 61.1 ± 9.7 vs 74.9 ± 14.9 min, P=0.008). Generation of thrombin and TAFIa during fibrinolysis was markedly reduced in FXI-Def samples ( Disclosures Peyvandi: NovoNordisk: Research Funding, speaker's fee Other; CSL Behring: speaker's fee, speaker's fee Other; LFB: speker's fee, speker's fee Other; Grifols: speaker's fee, speaker's fee Other; Bayer: speaker's fee Other; Baxter: speaker's fee Other; Biotest: Research Funding; Kedrion biopharma: Research Funding. Colucci:Boehringer Ingelheim : Research Funding.

Objective Variant alleles of the CYP2C9 gene encoding the cytochrome P450 (CYP) enzyme (2C9*2 [Arg144Cys] and 2C9*3 [Ile359Leu]) are known to increase the anticoagulant effect of warfarin and decrease the mean daily dose required to maintain the international normalized ratio (INR) of the prothrombin time within the target therapeutic range. However, little information is available on the effect of CYP2C9 polymorphisms on dose requirements during the most critical step of anticoagulant therapy, the induction phase. Methods This retrospective study evaluated the dosages given to 125 patients who started therapy with warfarin in a clinical center where physicians used the same approach for dosing and frequency of monitoring. CYP2C9 allelic variants were evaluated by polymerase chain reaction followed by restriction enzyme analysis. Results From the time of the first INR estimate (day 4) until the end of the induction phase (arbitrarily established at day 24), patients with 2C9*2 or 2C9*3 variant alleles required lower mean daily doses than patients carrying only wild-type alleles 2C9*1 (−17% and −40%, P < .0001). They also more frequently had INR values above the upper limit of the target range (3.0) (65% for 2C9*2/− and 66% for 2C9*3/− versus 33% for 2C9*1/*1; P = .006 and .012, respectively). Conclusions The requirement of smaller doses of warfarin in relation to CYP2C9 polymorphisms is already manifest on the fourth day of treatment, at the time of the first INR estimate. CYP2C9 genotyping is as yet not warranted, but frequent INR monitoring with appropriate dose adjustments is recommended during the first 3 weeks of treatment to avoid overanticoagulation and the inherent risk of bleeding in carriers of variant alleles. Clinical Pharmacology & Therapeutics (2004) 75, 198–203; doi: 10.1016/j.clpt.2003.09.015

Abstract 3312 The European Network of Rare Bleeding Disorders (EN-RBD) was established to bridge the gap between knowledge and practice in the care of patients with RBDs (rare bleeding disorders frequency Disclosures: Peyvandi: NovoNordisk, CSL Behring: Honoraria. Bidlingmaier:CSL Behring, Bayer Schering: Research Funding; CSL Behring, NovoNordisk, Pfizer, Bayer Schering: Membership on an entity's Board of Directors or advisory committees; Baxter, Biotest, CSL Behring, NovoNordisk, Pfizer, Bayer Schering: Honoraria. Schved:LFB, CSL Behring, Novonordisk, Bayer Schering: Research Funding.

Introduction: Some severe hemophiliacs (FVIII/FIX2000 (SB) IU/Kg/year. Patients who did not fit these criteria were considered as intermediate bleeders (IB). FVIII was measured by chromogenic assay and ETP was measured in platelet-rich plasma after addition of tissue factor. Results: 22MB, 22SB and 28IB were enrolled. MB had lower clinical and radiological scores when compared with both IB and SB (p SB (#22) IB (#28) MB (#22) p Age (yr) 38 (21–76) 38 (23–62) 32 (22–73) NS Age 1st bleed (yr) 1 (0–4) 2 (0–6) 3 (1–10) < 0.005 Bleeding episodes/yr 36 (25–60) 10 (3–20) 0 (0–2) < 0.0005 Factor use (IU/Kg/yr) 2207 (2040–8696) 1068 (207–2400) 60 (25–487) < 0.0005 Clinical score 18 (10–35) 10 (0–34) 3 (0–17) < 0.005 Pettersson score 44 (14–62) 28 (0–48) 17 (3–40) < 0.0005 Null mutations (%) 59 70 6 < 0.005 PTG20210A (%) 0 7 5 NS FV Leiden (%) 5 7 0 NS Median ETP (nM) 414 478 850 < 0.05

Summary. Prenatal diagnosis (PND) is an important issue in the comprehensive care of haemophiliacs. As a consequence of technological progress made in the field of PND, the early detection of an affected fetus provides the expectant couple with a chance to terminate pregnancy. This study was undertaken to assess the attitudes of two different haemophilic populations in Iran and Italy towards PND and termination of pregnancy. This study series included 59 Iranians (38 haemophilia A patients and 21 mothers) and 50 Italians (27 haemophilia A patients, 16 mothers and seven fathers). All the 109 participants received a questionnaire including demographic characteristics and evaluating the psychological effects stemming from PND and termination of pregnancy. Approximately 84.7% of the Iranians and 35.4% of the Italians were not familiar with the possibilities afforded by PND for haemophilia (P

The PRO-RBDD is a prospective study of fibrinogen and FXIII deficiency designed to collect data on demographics, laboratory phenotype, genotype, clinical manifestations, obstetric data, surgery, treatment type and its efficacy and safety. Central laboratory testing is also available for diagnosis confirmation and genotyping. The aims of the study are to evaluate the prevalence of bleeding episodes, establish the minimum coagulant activity level to prevent bleeding (spontaneous or post-traumatic), and to monitor patients’ therapeutic regimens (efficacy and complications). The PRO-RBDD network involved 52 Hemophilia Treatment Centers (HTCs) worldwide for a predicted 380 and 573 patients with fibrinogen and FXIII deficiency, respectively. Data collection started in February 2013 and will continue for 3 years (baseline and 6 follow-up visits are planned). Clinical bleeding episodes were classified into four categories of severity relying on the location and potential clinical impact as well as spontaneity of bleeding. Statistical analysis was performed using chi-square. Linear regression analysis was used to explore the association between coagulation factor activity level and clinical bleeding severity, with the relationship between the two variables defined through the coefficient β. Currently, 26 HTCs have obtained local ethical committee approval and 15 have started data entry for 89 and 109 fibrinogen and FXIII deficient patients, respectively. Demographic data showed a similar distribution between males and females with a median age of 21 years (range: 1-84) and 19 years (range: 3-71) for fibrinogen and FXIII deficiency respectively; 38% and 22% of fibrinogen and FXIII deficient patients, respectively, were children ( Follow-up data are available for up to 500 days for 51 and 28 patients with fibrinogen and FXIII deficiencies, respectively. Three out of 6 patients with fibrinogen deficiency (50%) on prophylaxis (30-45 mg/kg/month fibrinogen concentrate), experienced bleeding, while no bleeding was observed for 39 of the 45 fibrinogen deficient patients treated on-demand. Of the 14 patients with FXIII deficiency not on prophylaxis, 2 (14%) had spontaneous bleeds. No bleeding was reported for patients with FXIII deficiency on prophylaxis. No thrombotic events were recorded for any patients. Preliminary data from the PRO-RBDD study of patients with fibrinogen and FXIII deficiency confirmed a strong association between coagulant activity levels and clinical severity in both deficiencies, and the efficacy of prophylaxis in patients with FXIII deficiency. For fibrinogen deficiency, the optimal prophylactic treatment regimen requires further study. Abstract 2838. Table Fibrinogen patients FXIII patients Laboratory severity Severe undetectable Moderate 0.1-1 g/L Mild >1 g/L Severe undetectable Moderate 5-30% Mild >30% Bleeding severity Asymptomatic (no documented bleeding episodes) 1 (1%) 16 (19%) 12 (14%) 0 0 9 (10%) Grade I (bleeding after trauma or drug ingestion) 1 (1%) 7 (8%) 4 (5%) 2 (2%) 3 (3%) 2 (2%) Grade II (spontaneous minor bleeding) 4 (5%) 4 (5%) 5 (6%) 1 (1%) 1 (1%) 1 (1%) Grade III (spontaneous major bleeding) 22 (26%) 9 (10%) 0 70 (74%) 6 (6%) 0 Age at diagnosis median (min,max) 1.5 (0,24) 9 (0,84) 29 (0,64) 5 (0,54) 7 (0,36) 30 (2,46) Treatment type On demand 17 (20%) 38 (43%) 21 (24%) 8 (8%) 8 (8%) 7 (7%) Prophylaxis 11 (13%) 0 0 67 (71%) 2 (2%) 4 (4%) Disclosures Peyvandi: Biotest: Research Funding; Baxter: speaker's fee Other; Bayer: speaker's fee Other; Grifols: speaker's fee, speaker's fee Other; LFB: speker's fee, speker's fee Other; CSL Behring: speaker's fee, speaker's fee Other; NovoNordisk: Research Funding, speaker's fee Other; Kedrion biopharma: Research Funding. Mumford:NovoNordisk: Consultancy, speaker fee Other.