Contributions of side effects to contraceptive discontinuation and method switch among Kenyan women: a prospective cohort study.

OBJECTIVE: To determine the contribution of specific contraceptive side effects to method switch and modern-method discontinuation among Kenyan women. DESIGN: A prospective cohort study. SETTING: Five counties in Western Kenya. PARTICIPANTS: Women aged ≥18 years old and emancipated female minors ≥14 years old using modern, reversible contraception were recruited while attending 10 public health facilities. METHODS: Patient-reported adverse effect symptoms, method switch and discontinuation were reported through weekly text message-based surveys for 24 weeks. MAIN OUTCOME MEASUREMENTS: Prevalence, hazards ratio (HR). RESULTS: Among 825 women, 44% were using implants, 43% injectables, 7% an intrauterine device and 6% oral contraceptive pills at enrolment. Most (61%) women were continuing a method used in the previous month. During the 24-week follow up, incidence of contraceptive switch was 61.3 per 100 person-years (95% confidence interval [CI] 52.4-71.8) and incidence of discontinuation was 38.5 per 100 person-years (95% CI 31.6-47.0). On average, one-quarter (prevalence [Pr] 0.24, 95% CI 0.22-0.26) of participants reported side effects or method problems weekly, with sexual side effects the most prevalent symptom (Pr 0.15, 95% CI 0.13-0.16). Lack of expected bleeding was associated with higher risk of method switch (adjusted hazard ratio [aHR] 2.36, 95% CI 1.22-4.57). Risk of all-modern method discontinuation was higher among women experiencing irregular bleeding (aHR 2.39, 95% CI 1.20-4.77), weight changes (aHR 2.72, 95% CI 1.47-4.68) and sexual side effects (aHR 2.42, 95% CI 1.40-4.20). CONCLUSIONS: Addressing irregular bleeding, weight changes and sexual side effects through development of new products that minimise these specific side effects and anticipatory counseling may reduce method-related discontinuation. TWEETABLE ABSTRACT: Bleeding, weight changes, sexual problems associated with discontinuation of #contraception, but many continue despite side effects.

Post-authorization safety study of Clottafact® , a triply secured fibrinogen concentrate in congenital afibrinogenemia. A prospective observational study.

BACKGROUND AND OBJECTIVES: A new fibrinogen concentrate Clottafact® was developed according to European guidelines on plasma-derived products. A post-authorization safety study was set up in 2009 as part of the risk management plan. This was a non-interventional, prospective, non-comparative, multicenter study of the use of fibrinogen concentrate for congenital afibrinogenemia in real-life medical practice in France. MATERIALS AND METHODS: The analysis was descriptive and performed on 3 subgroups: prophylaxis vs. on-demand treatment, age (<6, <12 and ≥12) and severity of the deficiency. RESULTS: Fourteen patients [1-78 years] were included in 7 centres and followed for 1 year. Twenty-one adverse drug reactions (ADRs) classically reported with fibrinogen (pallor, chills, cough, vomiting, headache, urticaria and erythematous rash) were reported in 5 of 14 patients. Two ADRs were serious: an anaphylactic shock and a subclavian venous thrombosis with a favourable outcome without sequelae. In the nine patients under prophylaxis, 365 of 367 infusions were considered as successful (99·5%) and 2 as failures. For the five patients treated on-demand, the efficacy was rated as excellent for 27 of 48 infusions and good for the 21 others. CONCLUSION: This study confirms that the benefit/risk balance for this fibrinogen concentrate is favourable.

Open synovectomy of the ankle joint in young haemophiliacs: mid-term to long- term results of a single-centre series of 32 procedures.

INTRODUCTION: In haemophiliacs, recurrent hemarthrosis and chronic synovitis lead to chronic arthropathy. Synovectomy is indicated when medical treatment fails. Few studies report the results of open synovectomy of the ankle in haemophiliacs with a small number of procedures and also a limited follow-up. AIM: The aim of this paper is to report the long-term results of open surgical synovectomy of the tibio-talar joint. METHODS: Thirty-two open synovectomies were performed in 21 young haemophiliacs in the same haemophilia center using an antero-lateral and postero-medial approaches. The median follow-up was 15.4 years. Clinical (Petrini scores) and radiological evaluations (Pettersson scores) were made preoperatively and at each multidisciplinary follow-up visit. Wilcoxon and Spearman's tests were used for the statistical analysis. RESULTS: Preoperative median Petrini score was 6 (range 3-12), and improved at 2 and 5 years follow-up (P = 0.0003 and P = 0.0001 respectively). At 10 and 15 years follow-ups, median score remained below preoperative score (median 3.5, range 0-11). Ten ankles had a follow-up of more than 20 years. Preoperative median Petterson score presented a slight but continuous worsening in the first 2 and 5 years of follow-ups (P = 0.02, P = 0.003), but not correlation between clinical and radiological results was observed. CONCLUSION: Our long-term results support that clinical scores are improved even if radiological scores progress. Open synovectomy retards the progression of the arthropathy, but not stops it. Bleeding and pain are controlled and even if recurrence of bleedings is frequent, it is less severe, less painful and requiring less factors replacement.

Batch recall of French plasma-derived products due to variant Creutzfeldt-Jakob disease risk: the psychological impact on haemophilic patients, changes in their therapeutic demands and behaviour and ethical considerations.

The choice of plasma-derived products (PdP) vs. recombinant products (RP) for treating haemophilia is influenced by the infectious and perceived safety of the products. Batch recall of PdP due to the risk of variant Creutzfeldt-Jakob disease (vCJD) may have unfavourable psychological impacts on haemophilia patients and influence their product preferences. This study aimed to assess the psychological impact of batch recalls of PdP in six haemophilia patients and their therapeutic demands, and to discuss the ethical problems in physicians' management of this event. A survey was conducted using a new interview form and an existing anxiety and depression questionnaire. Batch recalls produce recurrent negative emotional outcomes in haemophiliacs and their families. The quality, understanding and efficiency of the batch recall announcements were unsatisfactory in some respects. Only one patient still had some of the vials in question, and only three patients understood the real reason for the batch recall. Four patients asked to change their PdP for RP; a fifth patient was considering doing so. Here, topics for discussion include the delivery of an unclear message to patients about a very uncertain risk of a frightening disease, the reasons to maintain PdP when RP are largely available, except in specific cases, and the related discomfort for caregivers. The ethical questions revealed by batch recalls and the high psychological impact of vCJD risk on patients can no longer be ignored, and require surveys assessing the rationales and choices of the healthcare authorities, manufacturers, prescribers and users.

Long-term follow-up of children with haemophilia - low incidence of infections with central venous access devices.

This study reports on 15 years of experience, in a single haemophilia care centre in France, with central venous access devices (VADs) in children with haemophilia. Following the insertion of a central VAD, patients were requested to return to the hospital on a quarterly basis for a multidisciplinary appointment which included clinical examination, chest X-ray, cardiac and major vessels ultrasound and preventive fibrinolysis. The family was urged to return to the Haemophilia Care Centre if complications or problems occurred. The follow-up comprised 50 patients. Data were collected prospectively. The total number of days with a VAD was 86 461 days and the total number of times the VAD was used was 41 192 (approximately every other day). Mean duration of VAD placement was 1269 days (range 113-2794 days). There were 25 complications, of which 9 haematomas and 5 systemic infections. Two VADs, infected with Staphylococcus aureus, had to be replaced. The infection rate was calculated as 0.0578 infections/1000 catheter days. There were no cases of thrombosis. This study concluded that most VAD infections in children can be avoided, even in patients requiring intense, prolonged treatment. The very low infection rate was achieved through the efforts of a multidisciplinary team, combined with extensive training for all individuals involved, adherence to written protocols and specific monitoring measures.

Immune tolerance induction in haemophilia A patients with inhibitors by treatment with recombinant factor VIII: a retrospective non-interventional study.

Immune tolerance induction (ITI) can overcome inhibitory factor VIII (FVIII) antibodies in haemophilia A patients receiving FVIII replacement therapy. The objective was to evaluate the use of sucrose-formulated, full-length recombinant FVIII (rFVIII-FS) for ITI therapy. Patients (<8 years at ITI start) with severe haemophilia A and a peak inhibitor titre >5 Bethesda units (BU) who underwent ITI with any rFVIII-FS dose for ≥ 9 months (or until success) were eligible for this retrospective study. Efficacy analyses included descriptions of ITI treatment regimens and outcomes; ITI success was determined solely at the discretion of the investigator. Safety analyses included assessment of adverse events. Of 51 enrolled patients, 32 [high dose (≥ 85 IU kg(-1) day(-1)), n = 21; low dose, n = 11] were eligible for analysis. ITI was successful in 69% (22/32) of patients (high dose, 66.7%; low dose, 72.7%) after a median of 1.4 years (range, 0.1-3.6 years). Influencing factors for ITI success were start of ITI <1 year after inhibitor detection and an inhibitor titre <10 BU at ITI start. All patients successfully tolerized with ITI continued to receive rFVIII-FS prophylaxis as maintenance therapy, with no inhibitor recurrence from the end of ITI until study enrolment. Use of rFVIII-FS for ITI was effective and well tolerated; success rates were similar to those in published studies.

Use of Haemate(®) P as immune tolerance induction in patients with severe haemophilia A who failed previous induction attempts: a multicentre observational study.

Immune tolerance induction (ITI) can eliminate factor VIII (FVIII) inhibitory antibodies that appear during FVIII replacement therapy. If first-line ITI fails, switching to a different FVIII concentrate, especially one containing von Willebrand factor (VWF), has been advocated. The objective of the study was to assess the efficacy and safety of Haemate(®) P, a plasma-derived FVIII concentrate containing high levels of VWF, as ITI in severe haemophilia A patients who had failed at least one prior ITI attempt with a different FVIII concentrate. In this multicentre, observational study, Haemate(®) P was administered at a starting dose of 83-308 IU kg(-1) day(-1) (1500-6000 IU day(-1)). Efficacy was assessed by standard criteria (e.g. Bethesda titre, FVIII recovery and half-life), and bleeding characteristics. Nine patients from six haemophilia centres were treated with Haemate(®) P after failing one (n = 2), two (n = 5) or three (n = 2) prior ITI courses. The median time from inhibitor detection to Haemate(®) P treatment was 5.4 years. The median Haemate(®) P dose was 134 IU kg(-1), and the median treatment duration 32 months. During median of 47 months of follow-up, complete response, partial response and treatment failure were observed in one, three and five patients respectively. Five patients experienced seven adverse events (AEs), including two serious AEs (sepsis). Haemate(®) P was discontinued due to an AE in one patient with a partial response. Haemate(®) P salvage ITI resulted in complete or partial tolerization in four of nine patients (44%) who had failed previous ITI attempts using different FVIII concentrates.

Spontaneous obturator internus muscle haematoma: a new unpublished cause of ilioipelvic pain in haemophilia.

Obturator muscles haematoma are rarely reported. The most often reported cases are primary pyomyositis or posttraumatic haematomas occurring during pelvic fractures. We firstly report herein two cases of spontaneous obturator internus haematoma (OIH) in two haemophiliacs with inhibitor. Clinical data and imaging of two patients treated in our clinic are reported here according to previously defined criteria of OIH in posttraumatic situation. Both patients were children suffering from severe and moderate haemophilia A, respectively, with an inhibitor at the time of the event. The clinical feature was marked by an iliopelvic pain letting discussing hip haemarthrosis, appendicitis or iliopsoas haematoma. For both patients ultrasonography (US) failed to provide the diagnosis. Careful and repeated clinical examinations eventually lead to suspect obturator haematoma which was confirmed by abdominopelvic computed tomography (CT) and magnetic resonance imaging (MRI). Respectively, high dose of FVIII or rFVIIa regimen allowed a rapid control of the muscular bleeding in the low and high responder inhibitor patients. Spontaneous OIH may be added to the differential diagnosis of iliopelvic pain in severe forms of haemophilia. US still often performed at first in such case remains unhelpful; abdominopelvic CT or MRI should be performed to discriminate among different diagnoses, including OIH which stays probably undiagnosed.

Screening for von Willebrand disease: contribution of an automated assay for von Willebrand factor activity.

Measuring von Willebrand factor (VWF) activity is essential to the diagnosis of von Willebrand disease (VWD). The VWF activity is usually assessed based on measurement of the ristocetin cofactor (VWF:RCo). However, that test is technically challenging and has high intra- and inter-assay variabilities. The HemosIL VWF activity (VWF:AC) is a fully automated assay, recently proposed as a good alternative to VWF:RCo for VWD diagnosis. This study was undertaken to assess this new method. First, the analytical performance of VWF:AC on an automated coagulo-meter (ACLTop) was determined, and then this new method was compared with VWF:RCo and the platelet function analyzer (PFA100) for 160 patients referred for VWD screening. The VWF:AC achieved acceptable precision with within-run and between-run coefficients of variation ranging from 2.3% to 14.1%, and linearity from 10% to 100%. Despite some marked differences between VWF:AC and VWF:RCo for 10 plasmas tested, their agreement for VWD diagnosis was good. The VWF:AC had sensitivity similar to that of PFA100 (close to 100%), but better specificity (97.7% vs. 66% or 60%, depending on the cartridge used). The good analytical performance, and the sensitivity and specificity of VWF:AC to detect VWF deficiency renders it a suitable method for VWD screening. Our findings support VWF:AC use for the diagnostic work-up of VWD, paying close attention to concomitant clinical signs and bleeding score, as recommended for VWD.

Deaths associated with acquired haemophilia in France from 2000 to 2009: multiple cause analysis for best care strategies.

Deaths occurring in the context of acquired haemophilia (AH) may be related to inter-connected causes and mechanisms including bleeding, specific or older patient co-morbidities or iatrogenic complications. However, their magnitude remains unknown. This study aimed to determine the respective weight and frequency of the various causes of death in AH. Multiple-cause analysis based on death certificates data is used in this purpose. Over a 10-year period (2000-2009), 121 deaths with AH as a cause were registered in France. All the deaths were of adults (extremes: 47 and 99 years; mean age: 80.7 years). The average number of causes per death certificate was 4.7. AH was the underlying cause of death (UCD) in 69.4% of the cases, and was more frequent in the older subjects. In contrast, before age of 75 years, AH was more often a contributing cause of death. No postpartum or obvious thromboembolism-related deaths were registered. Haemorrhagic shock was the most frequent direct cause of death (DCD), followed by infectious events, cardiac dysfunction, metabolic and nutritional disorders with muscle wasting and decubitus complications, and cancers (52.9%, 26.4%, 7.5%, 5.8% and 4.1%, respectively). However, when AH was not reported as an UCD, infections become the first DCD (32.4%) followed by bleeding events (16.2%). Best prophylactic and curative strategies for infections are particularly required to improve the prognosis in AH. Moreover, as several of its DCD correspond also to steroids side effects, best tolerated immunosuppressant regimen with steroid-sparing agents adjoining are particularly awaited in AH population.

Uncomplicated neurosurgical resection of a malignant glioneuronal tumour under haemostatic cover of rFVIIa in a severe haemophilia patient with a high-titre inhibitor: a case report and literature review of rFVIIa use in major surgeries.

The development of inhibitors following factor VIII replacement therapy is a serious complication in severe inherited haemophilia. Whereas significant experience, notably in orthopaedic surgery, is now obtained with the use of bypassing agents in haemophilia with high-titre inhibitor, new surgical challenges might occur due to patients' increasing life expectancy. A 56-year-old severe haemophilia A patient with a high-titre inhibitor was diagnosed for probable right temporoparietal malignant glioneuronal tumour on cerebral magnetic resonance imaging (MRI) (4 cm x 3 cm cerebromeningeal tumour with perilesional oedema and transfalcial herniation) requiring total resection. Then recombinant activated FVII (rFVIIa) was chosen as the haemostatic agent: bolus of 270 microg kg(-1) every 2 h during the first 24 h, 180 microg kg(-1) every 3, 4 and 6 h, respectively, at days 2-3, from days 4-10 and finally from days 11-15. Tranexamic acid was associated. Pre- and postoperative courses were uneventful, the surgical procedure being assessed at optimal haemostatic condition without any unusual haemorrhage on MRI controls, diffuse intravascular coagulation criteria or thromboembolic event. Intensive rFVIIa therapy has shown to be safe and effective in this first reported neurosurgery about a malignant tumour exhibiting to a high-bleeding risk notably in haemophilia with high-titre inhibitor. The use of lower doses of rFVIIa might have been possible; however, in the absence of accurate test for monitoring rFVIIa therapy, the potentially life-threatening complications of this procedure required maximum haemostasis with high rFVIIa doses.

Treatment of severe von Willebrand disease with a high-purity von Willebrand factor concentrate (Wilfactin): a prospective study of 50 patients.

BACKGROUND AND OBJECTIVES: A plasma-derived von Willebrand factor (VWF) concentrate with low factor VIII (FVIII) content was specifically developed to treat von Willebrand disease (VWD). Efficacy and safety were investigated by merging the results of two comparable protocols conducted prospectively in 5 European and 12 French centers. METHODS AND RESULTS: Fifty patients with clinically severe VWD (72% had VWF ristocetin cofactor activity less than 10 IU dL(-1) and 46% had FVIII < 20 IU dL(-1)) were treated with the concentrate as the only therapy, except for clinical situations requiring a priming dose of FVIII to rapidly correct an intrinsic coagulation defect. A total of 139 spontaneous bleeding episodes were treated; only 53 (38%) needed a concomitant FVIII dose. Outcome was excellent or good in 89% of the episodes. Forty-four patients underwent 108 surgical or invasive procedures. Outcome was excellent or good in 95 scheduled procedures (only VWF was infused) and 13 emergency procedures (a priming FVIII dose was co-administered with the first VWF infusion). There were no thrombotic complications and none of the 18 patients with type 3 VWD developed anti-VWF or anti-FVIII antibodies. CONCLUSIONS: This concentrate safely and effectively provides hemostasis in patients with clinically severe VWD.

Impact of choice of treatment for bleeding episodes on inhibitor outcome in patients with mild/moderate hemophilia a and inhibitors.

Patients with mild/moderate hemophilia A (MHA) may develop inhibitors to factor VIII (FVIII). In this condition, FVIII clotting activity (FVIII:C) baseline levels may remain stable for some patients, but may be reduced to less than 0.01 U/mL for others. Several risk factors for the development of inhibitors in MHA have been proposed. Genetic factors, such as mutations in the FVIII gene, may play a central role; however, other influences, such as intensive treatment with FVIII products, may also be important. Optimal treatment regimens have yet to be determined, not only for the eradication of inhibitors, but also for the management or surgical prophylaxis of hemorrhages associated with this condition. Several treatment options for the control of bleeding in patients with MHA and inhibitors (MHAI) are currently available, and the choice of therapeutic strategy should be given careful consideration; some treatments may produce an anamnestic response, thus delaying the return to FVIII:C baseline levels and adversely affecting the duration of the severe bleeding phenotype. To increase our knowledge of MHAI, a retrospective collection of data is currently being performed among hemophilia centers in France and Belgium. Based on five examples of patients with MHAI collated from preliminary study data, we illustrate the impact on inhibitor outcome of the therapeutic choices used to treat bleeding episodes in these patients.

Linkage of genetic markers on human chromosomes 20 and 12 to NIDDM in Caucasian sib pairs with a history of diabetic nephropathy.

The potential contribution of maturity-onset diabetes of the young (MODY) genes to NIDDM susceptibility in African-American and Caucasian NIDDM-affected sibling pairs with a history of adult-onset diabetic nephropathy has been evaluated. Evidence for linkage to NIDDM was found with polymorphic loci that map to the long arms of human chromosomes 20 and 12 in regions containing the MODY1 and MODY3 genes. Nonparametric analysis of chromosome 20 inheritance data collected with the MODY1-linked marker D20S197 provides evidence for linkage to NIDDM with a P value of 0.005 in Caucasian sib pairs using affected sibpair (ASP) analyses. Non-parametric analysis of chromosome 12 inheritance data collected with the MODY3-linked markers D12S349 and D12S86 provides evidence for linkage to NIDDM with P values of 0.04 and 0.006, respectively, in Caucasian sib pairs using similar analyses. No evidence for linkage of MODY1 and MODY3 markers to NIDDM in African-American sib pairs was observed. In addition, no evidence for linkage to MODY2 (glucokinase-associated MODY) was observed with either study population. Results of multipoint maximum logarithm of odds (LOD) score analysis were consistent with the ASP results. A maximum LOD score of 1.48 was calculated for linkage to MODY1-linked loci and 1.45 to MODY3-linked loci in Caucasian sib pairs. Tabulation of allele sharing in affected sib pairs with D20S197 and D12S349 suggests that affected sibling pairs may inherit susceptibility genes simultaneously from chromosome 20 and chromosome 12. The results suggest that genes contributing to NIDDM in the general Caucasian population are located in the regions containing the MODY1 and MODY3 genes.

Anti-A2 and anti-A1 domain antibodies are potential predictors of immune tolerance induction outcome in children with hemophilia A.

BACKGROUND: Hemophilia A (HA) is a congenital bleeding disorder resulting from factor VIII deficiency. The most serious complication of HA management is the appearance of inhibitory antibodies (Abs) against injected FVIII concentrates. To eradicate inhibitors, immune tolerance induction (ITI) is usually attempted, but it fails in up to 30% of cases. Currently, no undisputed predictive marker of ITI outcome is available to facilitate the clinical decision. OBJECTIVES: To identify predictive markers of ITI efficacy. METHODS: The isotypic and epitopic repertoires of inhibitory Abs were analyzed in plasma samples collected before ITI initiation from 15 children with severe HA and high-titer inhibitors, and their levels were compared in the two outcome groups (ITI success [n = 7] and ITI failure [n = 8]). The predictive value of these candidate biomarkers and of the currently used indicators (inhibitor titer and age at ITI initiation, highest inhibitor titer before ITI, and interval between inhibitor diagnosis and ITI initiation) was then compared by statistical analysis (Wilcoxon test and receiver receiver operating characteristic [ROC] curve analysis). RESULTS: Whereas current indicators seemed to fail in discriminating patients in the two outcome groups (ITI success or failure), anti-A1 and anti-A2 Ab levels before ITI initiation appeared to be good potential predictive markers of ITI outcome (P < 0.018). ROC analysis showed that anti-A1 and anti-A2 Abs were the best at discriminating between outcome groups (area under the ROC curve of > 0.875). CONCLUSION: Anti-A1 and anti-A2 Abs could represent new promising tools for the development of ITI outcome prediction tests for children with severe HA.

Twenty-four novel hemophilia B mutations revealed by rapid scanning of the whole factor IX gene in a French population sample.

Full scanning of the factor IX gene by means of denaturing gradient gel electrophoresis enabled us to determine the molecular defects in 48 out of 49 hemophiliacs and to evaluate the spectrum of factor IX mutations in the French population. Our results further document the high molecular heterogeneity of the disease and the efficiency of this rapid screening method for disease-causing mutations. This direct approach, which is based on computer-aided analysis of the whole coding, promoter and exon-flanking factor IX gene sequences, proved to be helpful for carrier detection and prenatal diagnosis in most hemophilia B families, including sporadic cases. Moreover, we were able to identify 24 novel molecular defects of various natures in the factor IX gene.

Detection of colorectal cancer K-ras mutations using a simplified oligonucleotide ligation assay.

It has been suggested that some mutations in codons 12 and 13 of the K-ras gene are associated with the progression of colorectal adenomas to carcinomas. The aim of this study was to develop a rapid, colorimetric assay for K-ras point mutations commonly associated with colorectal cancer. K-ras exon 1 was amplified from colorectal tumor DNA and K-ras activating mutations detected using an oligonucleotide ligation assay (OLA) in combination with immunological and colorimetric detection. Using the OLA with oligonucleotides specific to individual K-ras mutations, 6 (of 17 total colorectal adenomas/carcinomas) were found to have K-ras mutations. The assay could detect as little as 10% mutant allele. A simplified OLA designed to test for either the presence (+) or absence (-) of any of the K-ras activating mutations was developed. The assay was further streamlined by use of a dipstick methodology for colorimetric development. If required, assay sensitivity can be increased by the use of the recently described EDNA-ELCA detection system. The simplified (+/-) mutation OLA in combination with a dipstick or EDNA-ELCA detection system provides a rapid, sensitive assay for K-ras point mutations suitable for use as part of the clinical assessment of colorectal cancer.

Multicenter retrospective study on the utilization of FEIBA in France in patients with factor VIII and factor IX inhibitors. French FEIBA Study Group. Factor Eight Bypassing Activity.

Factor VIII or factor IX replacement is frequently impossible in inhibitor-developing hemophiliacs, because of the level of the inhibitor titer. Activated prothrombin complex concentrates are one of the available options to treat the bleeding episodes in such patients. However, the efficacy of these products and the associated thrombogenic risk, particularly in prolonged administration such as employed during surgeries, are important concerns for hemophilia care providers. We performed a multicenter retrospective study to evaluate the use of FEIBA (Factor Eight Bypassing Activity) in France, and data is presented on 433 bleeding episodes, including surgical procedures, concerning 60 patients from 15 hemophilia centers. The efficacy was judged as good or excellent in 352 episodes (81.3%), poor in 73 episodes (16.9%) and non-existent in 8 episodes (1.8%). Minor and major surgical procedures were successfully performed using FEIBA as a second-line therapy after human or porcine factor VIII, and in some occasions FEIBA was utilized as the only substitution product. The tolerance was assessed as good in 428 episodes (98.8%), but in 5 cases adverse effects were reported. Only 3 patients out of 52 regularly evaluated (5.8%) were HIV-seropositive, and for two of them the seroconversion occurred prior to the first use of FEIBA. In contrast, 80.4% of the patients were HCV-seropositive. An anamnestic response after the administration of FEIBA was noted in 31.5% of cases. This study points out the main features of the use of FEIBA in France, and particularly the low HIV seroprevalence in the patients treated. The good efficacy and the excellent tolerance still confer to this product a place to consider in the therapeutic options for the treatment of inhibitor-developing hemophiliacs or in acquired hemophilia.

Mapping and functional studies of two alloantibodies developed in patients with type 3 von Willebrand disease.

Inhibitors against von Willebrand factor (vWF) developed in two unrelated multitransfused patients (patients 1 and 2) with severe (type 3) von Willebrand disease (vWD) were analyzed. Both inhibitors were identified as antibodies of the IgG class by ELISA using immobilized purified vWF and either serum or purified Ig from the patients. Typing, mapping and functional studies of both antibodies revealed significantly distinct properties. Patient 1 antibody contained all subclasses of IgG (1, 2, 3 and 4) whereas antibody from patient 2 was a mixture of only IgG1 and 4. By ELISA using a series of immobilized purified proteolytic fragments of vWF, patient 1 antibody mainly bound to fragment SpIII and, to a lower extent, to fragments SpII and SpI; it poorly bound to P34 and the 39/34 kDa fragment. In contrast, patient 2 antibody only bound to fragments corresponding to the N-terminal portion of vWF but failed to bind to SpII. Functional studies were performed by testing the capacity of each antibody to inhibit vWF binding to its various ligands. Both antibodies blocked vWF binding to Factor VIII (FVIII), fibrillar type III collagen, bitiscetin and the subsequent induced binding to GPIb. Patient 1 antibody also blocked vWF binding to platelet GPIb when induced by ristocetin. However it failed to block vWF binding to GPIb when induced by botrocetin as well as the binding of botrocetin itself to vWF. Our data thus suggest that this inhibitor does not recognize the GPIb-binding site on vWF but the sites of vWF involved in its interaction with ristocetin. In contrast, we observed that patient 2 antibody blocked vWF binding to platelet GPIb induced by either agonist as well as vWF binding to botrocetin. Finally, the effect of the antibodies was tested on vWF binding to GPIIb/IIIa. As expected from the mapping experiments, only IgG from patient 1 blocked the interaction while IgG from patient 2 had no effect. In conclusion, we have shown that two multitransfused patients with type 3 vWD have developed alloantibodies with similar properties to those of polyclonal antibodies but with distinct effects on the functions of vWF.