BACKGROUND:  Currently available coronavirus disease 2019 (COVID-19) vaccines are approved for intramuscular injection and efficacy may not be ensured when given subcutaneously. For years, subcutaneous vaccination was recommended in patients with hemophilia to avoid intramuscular bleeds. Therefore, recommendations for the application of COVID-19 vaccines are needed.
METHODS:  The Delphi methodology was used to develop consensus recommendations. An initial list of recommendations was prepared by a steering committee and evaluated by 39 hemophilia experts. Consensus was defined as ≥75% agreement and strong consensus as ≥95% agreement, and agreement as a score ≥7 on a scale of 1 to 9. After four rounds, a final list of statements was compiled.
CONCLUSIONS:  Consensus was achieved that COVID-19 vaccines licensed only for intramuscular injection should be administered intramuscularly in hemophilia patients. Prophylactic factor replacement, given on the day of vaccination with a maximum interval between prophylaxis and vaccination of 24 hours (factor VIII and conventional factor IX concentrates) or 48 hours (half-life extended factor IX), should be provided in patients with moderate or severe hemophilia. Strong consensus was achieved that patients with mild hemophilia and residual factor activity greater than 10% with mild bleeding phenotype or patients on emicizumab usually do not need factor replacement before vaccination. Swelling, erythema, and hyperthermia after vaccination are not always signs of bleeding but should prompt consultation of a hemophilia care center. In case of injection-site hematoma, patients should receive replacement therapy until symptoms disappear.
CONCLUSIONS:  Consensus was achieved on recommendations for intramuscular COVID-19 vaccination after replacement therapy for hemophilia patients depending on disease severity.

暂无摘要。

In hemophilia A and B, analysis of the F8 and F9 gene variants enables carrier and prenatal diagnosis and prediction of risk for the development of inhibitors. The PedNet Registry collects clinical, genetic, and phenotypic data prospectively on more than 2000 children with hemophilia. The genetic reports of F8/F9 gene variants were classified uniformly to Human Genome Variation Society nomenclature and reevaluated using international population- and disease-specific databases, literature survey and, where applicable, computational predictive programs. We report 88 novel variants in the F8 and F9 genes, 80 fulfilling criteria for Class 5 (pathogenic), six for Class 4 (likely pathogenic) and two fulfilling criteria for Class 3 (variant of unknown significance) of the American College of Medical Genetics and Genomics/Association for Molecular Pathologyguidelines together with information on the respective phenotype and inhibitor formation. The study highlights the need to reevaluate and update earlier genetic reports in hemophilia both locally but also in variant databases in light of changed nomenclature and new guidelines.

暂无摘要。

Replacement therapy with plasma-derived or recombinant FVIII and FIX (pdFVIII/pdFIX or rFVIII/rFIX) concentrates is the standard of treatment in patients with haemophilia A and B, respectively. Measurement of factor VIII (FVIII:C) or factor IX (FIX:C) levels can be done by one-stage clotting assay (OSA) or chromogenic substrate assay (CSA). The French study group on the Biology of Hemorrhagic Diseases (a collaborative group of the GFHT and MHEMO network) presents a literature review and proposals for the monitoring of FVIII:C and FIX:C levels in treated haemophilia A and B patients, respectively. The use of CSA is recommended for the monitoring of patients treated with pdFVIII or rFVIII including extended half-life (EHL) rFVIII. Except for rFVIII-Fc, great caution is required when measuring FVIII:C levels by OSA in patients substituted by EHL-rFVIII. The OSA is recommended for the monitoring of patients treated with pdFIX or rFIX. Large discordances in the FIX:C levels measured for extended half-life rFIX (EHL-rFIX), depending on the method and reagents used, must lead to great attention when OSA is used for measuring FIX:C levels in patients substituted by EHL-rFIX. Data of most of recent studies, obtained with spiked plasmas, deserve to be confirmed in plasma samples of treated patients.

Assay discrepancies can occur with laboratory monitoring of FVIII and FIX replacement therapy, particularly for the extended half-life products. This guideline collates current published data and provides advice on appropriate choice of assays for laboratory measurement of replacement therapy for patients with Haemophilia A and B without inhibitors. It is recommended that each haemophilia centre should ensure that appropriate laboratory assays are available for FVIII and FIX products in local clinical use. Patient samples should be assayed against calibrators traceable to WHO Plasma International Standards. Assay discrepancies are common especially for the extended half-life FVIII and FIX products, and assays of these products may need to be verified with the specific CFC being used.

BACKGROUND: This report summarizes recommendations relating to haemophilia therapy arising from discussions among experts from 36 European countries during the \'Kreuth IV\' meeting in May 2016.
OBJECTIVE: The objective of the meeting was for experts in the field of haemophilia from across Europe to draft resolutions regarding current issues relating to the treatment of haemophilia.
RESULTS: Hospitals providing clinical care for people with haemophilia and related disorders are strongly recommended to seek formal designation as either European Haemophilia Treatment Centres (EHTC) or European Haemophilia Comprehensive Care Centres (EHCCC). There should be agreed national protocols or guidelines on management of the ageing patient with haemophilia. The minimum consumption of factor VIII and IX concentrate in any country should be 4 IU and 0.5 IU per capita of general population respectively. Treatment for hepatitis C with direct-acting antiviral agents should be provided to all people with haemophilia on a priority basis. Genotype analysis should be offered to all patients with severe haemophilia. Genetic counselling, when given, should encompass the recommendation that genetic relatives of the affected person be advised to seek genetic counselling. People with inhibitors should have access to bypassing agents, immune tolerance and elective surgery. National or regional tenders for factor concentrates are encouraged. Outcome data including health related quality of life should be collected. Treatment with extended half-life factors should be individualized and protection against bleeding should be improved by increasing trough levels. Steps should be taken to understand and minimize the risk of inhibitor development.
CONCLUSIONS: It is hoped that these recommendations will help to foster equity of haemophilia care throughout Europe.

BACKGROUND: Prophylactic replacement with factor concentrate is the optimal treatment for persons with severe haemophilia to avoid or minimize bleeding. This ultimately prevents or reduces joint disease and improves life expectancy and quality of life towards values matching those in the normal population. However, uncertainty still exists around the optimal regimens to be prescribed for prophylaxis. An increasing number of treating physicians and patients are showing interest in patient-tailored approaches to prophylaxis, which aim to harmonize the prophylaxis regimen with the patients\' bleeding phenotype, levels of physical activity and a variety of other variables.
METHODS: A modified Delphi technique was adopted to generate consensus. The expert panel met in person to set the objectives, be trained on the Delphi technique and agree on the desired level of consensus. Three iterations were used to identify the targets, the scenarios and their combinations.
RESULTS: Twenty-eight scenarios and eight target levels were identified and used to issue recommendations. The panel reached the desired level of consensus on positive or negative recommendations. Areas where consensus was not reached were identified and proposed as areas for future research. Prospective assessment of the validity of most of the proposed targets is recommended.
CONCLUSIONS: We have generated, by expert consensus, target plasma levels of factor concentrate to be used to tailor treatment for persons with haemophilia.

This paper reviews the current status on recommendations or guidelines for primary prophylaxis based on recent published papers from organizations or group of experts as well as some original key papers. A rather uniform view exists that prophylaxis should be initiated at an early age before or after no more than a single joint bleed and, if possible, preferably be continued for life. The dose and dose frequency of prophylaxis is dependent on the goal of treatment, bleeding phenotype, compliance, venous access and economic resources in the health care system and should be tailored individually based on clinical outcome and pharmacokinetics. For children, the effectiveness of prophylaxis is more dependent on maintaining minimum trough levels than in adults. Novel extended half-life products are being introduced, which should not affect the decision on when to start prophylaxis nor the initial dose, but which may be helpful for patients with difficult venous access and which may enable higher trough levels of factor VIII.

We herein report our experience of successfully managing the hemostatic system by controlling serum factor IX levels throughout the perioperative period in a patient with hemophilia B. Coronary artery bypass grafting with cardiopulmonary bypass was planned for a 52-year-old man with moderate severity of hemophilia B. During surgery, recombinant factor IX (rFIX; BeneFIX(®) Pfizer Japan inc., Tokyo, Japan) was administered by bolus infusion followed by continuous infusion as per the guidelines of the Japanese Society on Thrombosis and Hemostasis. The operative course was uneventful without any considerable bleeding or complications.