About 31% of the patients with a factor VIII replacement therapy develop a factor VIII inhibitor.From these are 23% low-responder ( 5BE) [8].In the case of severe hemophilia B,about 10.5% of the patients develop inhibitory antibodies [9]. Anti-factor VIII-antibodies are also seen in 15 78% healthy people without hemophilia [7, 17, 19]. Lacroix-Desmazes et al. [10, 11] showed anti-idiotypic antibodies neutralizing the inhibitory activity of the an- factor VIII antibodies in healthy people. Well-known predisposing factors for inhibitor formation are genetic features of factor VIII,which include large deletions,nonsense mutations or intrachromosomal recombinations [5, 23].Also, ethnic groups other than Caucasians (e.g.Africans) have a higher risk of developing inhibitors.Other risk factors are presumably de- ved from the immune system. For instance, a reduction of the inhibitor was seen with lower CD4+ T helper cell counts in HIV positive hemophilic patients [3,4].The development of inhibitors is very likely to be a Th-2 mediated event where cyto- nes and their receptors,T-cell receptors and the Major Histocompatibility Complex may also play an important role. Theoretical Background The substituted factor is an unknown protein for patients with a severe he- philia. Fig. 1. The normal immunoresponse (according to BAENKLER [2]) Abbreviations: TCR T cell-receptor; APC antigen presenting cell 36 I.Wieland et al.

Epidemiology

HIV Infection and Causes of Death in Patients with Hemophilia in Germany (Year 2004/2005 Survey)
Development of the German Hemophilia Register
National Hemophilia Registry - Source of Information about the Quality of Hemophilia Medical Care in a Developing Country
Hemophilia Therapy - Management of Bleedings and Inhibitors
Regulation of Factor VIII Life-Cycle by Receptors from LDL Receptor Superfamily
Update of the Inhibitor-Immunology-Study
Therapy of Acquired Hemophilia - Immunoadsorption and Rituximab Treatment for Immunosuppression and Substitution of Coagulation Factors
Orthopedic Treatment in Hemophiliacs
Osteoporosis and Hemophilia - Is there a Correlation and Is there a Problem?
Orthopedic Evaluation of the Lower Extremity in 249 Children: A Multicenter Trial
Simultaneous Bilateral Total Knee Arthroplasty in Hemophilic Arthopathy
Alternative Therapy such as the Acupuncture of the Skull for Hemophilic Arthropathy
Endoprosthetics of Large Joints in Patients Infected with HIV
Hemostaseologic Diagnostics
Factor VIII Methods: Which Assay Principle for which Indication?
Global ECAT Survey on Factor VIII Inhibitor Testing: Results of an Inter-Laboratory Pilot Study
A Practical Concept for Pre-Operative Identification and Improved Management of Patients at Risk for Bleeding
Pediatric Hemostaseology
Intravascular Tissue Factor in Cord vs Adult Whole Blood
Perioperative Coagulation Screening in Children - Reasons and Results
Thrombin Generation in Children
Free Lectures
Working-Group of the German Hemophilia Assistants - History, Purpose and Goals
The Endogenous Thrombin Potential as a New Parameter for the Peri-Operative Monitoring in Conjunction with Endo-Prosthetic Supply due to Hemophilic Arthropathy
Identification of Inhibitor Epitopes in Acquired Hemophilia by Phage Display
Spectrum of Molecular Defects and Mutation Detection Rate in Patients with Mild and Moderate Hemophilia A
Recombinant Factor VIIa for Major Surgery in Severe Factor XI Deficiency: Pharmacodynamic Monitoring Using Thromboelastometry
Poster
Establishment of a Web-Based Documentation System for Quality Assurance of Hemophilia Treatment in Mecklenburg/Western Pomeranian: a Pilot Study
Successful Angiographic Embolization of Recurrent Elbow Joint Bleeds in one Patient with Severe Hemophilia A
Evaluation of Thrombotic Events in Hemophiliacs Undergoing Major Orthopedic Surgery Without Thrombosis Prophylaxis
Motivating Patients and Parents to Document Treatment Correctly
Fit for Life Competition: Everyone's a Winner
Blood Borne Infections in Hemophiliacs in a Developing Country. A Single Center Experience
Hemophilia Center Frankfurt - Twinning Center for Nairobi/Kenya
Economic Evaluation of Orthopedic and Surgical Interventions in Hemophiliacs - Not Only Direct Medical Costs Matter
The Occurrence of Factor VIII Inhibitor in a Patient with Mild Hemophilia A - During Treatment with Interferon for Chronic Hepatitis C
Severe Hemophilia A Patient with High-Titer Inhibitor, use of TGA in the Monitoring of Bypassing Therapy
EUREKA - an European Registry for Orthopedic Surgery in Hemophiliacs with Inhibitors
Double Balloon Enteroscopy (DBE) with Argon Plasma Laser Coagulation (APC) for a Patient with Heyde's Syndrome
Successful Liver Transplantation in a Patient with Anti-Thrombocyte Antibodies and Severe Hemophilia A
Peri- and Postoperative Course of 95 Patients with von-Willebrand's Disease
Pregnancy in a Patient with Congenital Antithrombin Deficiency
Successful Inhibitor-Elimination with Rituximab in Acquired Hemophilia A and a Patient with a Carrier Status for Hemophilia A: Two Case Reports
An Interesting Family Case of von-Willebrand-Syndrome
Clinical Manifestations of Dysfibrinogenemia in Relation to the Fibrinogen Gene Mutation
Thrombin Generation in a Hemophilic Newborn
Rapid and Sensitive Detection of Heterozygous Deletions of one or more Exons in Hemophilia A Females by Multiplex PCR and DHPLC Technique
Molecular Genetic Analysis in Patients with Inherited Factor V Deficiency
Expression Analysis of C1-Inhibitor Mutants Confirms Causality of Missense Mutations for Hereditary Angioedema
Expression of the ?-Glutamyl Carboxylase (GGCX) Containing the Arg485Pro Mutation Found in two Unrelated VKCFD1 Patients
Concentration of Soluble Endothelial Protein C Receptor (EPCR) in Plasma in Relation to Age, Sex, BMI and Hemostasis Parameters
Thrombin Generation is Age-Dependent in Children as well as in Adults
Effects of PFA-100 in Preoperative Screening for von Willebrand Disease in 310 Patients
Control of Aspirin Effect in Chronic Cardiovascular Patients Using two Whole Blood Platelet Function Assays: PFA-100 and Multiple Electrode Aggregometry
Difficulties in the Interpretation of the Term »Patient-Related« in the Scope of the Introduction of a Remuneration of Additional Payments According to the OPS
Factor VIII as Positive Regulator of Activated Platelets
Characterization of Three Novel Mutations in the Sodium Binding Site of Coagulation Factor X
Characterization of a Mutation in the 5? Flanking Region and a Novel IVS7 Splice site Mutation in a Patient with Severe FVII Deficiency
On the Molecular Basis of Warfarin Resistance in Rats
Influence of Factor VHR2 on Endogenous Thrombin Potential and Clinical Phenotype in Factor VII Deficiency
Splice Site Mutations Effect on the F8 mRNA Splicing
Species-Specific Variation of VKORC1-Activity and Resistance to Warfarin
Various Missense Mutations in the Vitamin K Epoxide Reductase Complex Subunit 1 (VKORC1) Cause Hereditary Coumarin Resistance
Establishment of an International Registry of Patients with Congenital FXIII Deficiency
The Impact of Freezing of Plasma Samples, AB0 Blood Group and Acute-Phase Reaction on Detecting Mild Factor VIII Deficiency and Increased Factor VIII Levels as a Risk Factor for Venous Thromboembolism
Thrombin Generation in Severely Obese Children.