Search

Background: Inhibitor development in previously untreated patients (PUPs) with severe haemophilia A is a multifactorial event. It is unknown whether paediatric vaccinations given in close proximity to factor VIII (FVIII) are associated with inhibitor development. Objective: To assess whether paediatric vaccinations in close proximity to FVIII within the first 75 exposure days (EDs) are associated with inhibitor development in PUPs with severe haemophilia A. Methods: We included 375 PUPs with severe haemophilia A (

Summary. The development of neutralizing antibodies against factor VIII (FVIII) is a major complication of treatment with FVIII in patients with severe haemophilia A. This study was designed to describe the relationship between the type and location of the factor 8 (F8) gene mutation and the development of clinically relevant inhibitors in patients with severe haemophilia A. We conducted a single centre cohort study among 318 consecutive patients (baseline FVIII activity level

In 1995, AAFACT, a new monoclonal purified factor VIII concentrate (FVIII), derived from human plasma, was introduced in the Netherlands. The monoclonal purification based production process includes a viral inactivation step by solvent/detergent treatment. Products manufactured according to this procedure, for example Hemofil M are used worldwide. The aim of the present study was to assess inhibitor development in a large cohort of previously treated patients (PTPs) who were followed up for 10 years. In addition, efficacy, HIV and hepatitis C virus (HCV) transmission, and allergic reactions were monitored. All 165 patients with severe haemophilia A (FVIII

Immune tolerance induction (ITI) is described in a patient with severe haemophilia B complicated by the presence of an inhibitor. A number of ITI regimes were attempted without success and the patient suffered from frequent relapses and bleeding episodes. Successful ITI was achieved with the additional use of cyclosporin A. The patient developed nephrotic syndrome although had a negative Bethesda titre at this time. When cyclosporin A therapy was ceased, the inhibitor titre rose and the patient suffered again from bleeding episodes. Cyclosporin A was reintroduced at a lower dose. The patient has now received cyclosporin A for 10 years, during which time he has relapsed three times for short periods (2 weeks). He is also on prophylaxis with factor IX three times a week with preinfusion levels >1% and without bleeding.

Summary. Measurement of joint health is critically important when assessing children with haemophilia. Few measures exist; they lack sensitivity to small changes, don't account for normal development and were never formally validated. To address these concerns, the Hemophilia Joint Health Score (HJHS) was developed by modifying existing scores. Objective: To test the inter-observer and test–retest reliability of the HJHS. Methods: Using a fully factorial design, four physiotherapists (from Canada, the United States and Sweden) examined eight boys with severe haemophilia A on two consecutive days using the HJHS. The boys ranged in age from 4–12 years and presented with variable joint damage. Six index joints (elbows, knees and ankles) were assessed on 11 impairment items including swelling, flexion and extension loss and gait. Concordance was measured by the intra-class correlation co-efficient. Results: Reliability of the HJHS was excellent with an inter-observer co-efficient of 0.83 and a test–retest of 0.89. Conclusion: This study is the first in a series to assess the psychometric properties of the HJHS, a promising new measure of joint health in boys with haemophilia.

Many haemophilia patients were infected with hepatitis C virus (HCV) in childhood after transfusion with inadequately or non-virus inactivated clotting factor products. Limited information is available on the clinical course of HCV infection in children. To assess the clinical consequences of hepatitis C in these young patients we performed a pilot study of 31 patients with haemophilia, infected with HCV before the age of 13. Current median age was 20 years. Nineteen (61%) patients had chronic hepatitis C, whereas the remaining 12 patients spontaneously cleared HCV. The median duration of infection was 17 years. Among patients chronically infected with HCV, an enlarged liver and/or spleen on ultrasound was present in 59%, whereas 63% had abnormal aminotransferases and/or gamma-GT values. In conclusion, 39% of the patients infected in childhood cleared HCV spontaneously. The majority of the patients with chronic hepatitis C had ultrasound and/or laboratory abnormalities and these findings may be associated with the presence of chronic liver disease.

Routine infusions of factor VIII to prevent bleeding, known as prophylaxis, and other intensive therapies are being more broadly applied to patients with haemophilia. These therapies differ widely in replacement product usage, cost, frequency of venous access and parental effort. In order to address residual issues relating to recommendations, implementation, and evaluations of prophylaxis therapy in persons with haemophila, a multinational working group was formed and called the International Prophylaxis Study Group (IPSG). The group was comprised of haemophilia treaters actively involved in studies of prophylaxis from North America and Europe. Two expert committees, the Physical Therapy (PT) Working Group and the Magnetic Resonance Imaging (MRI) Working Group were organized to critically assess existing tools for assessment of joint outcome. These two committees independently concluded that the WFH Physical Examination Scale (WFH PE Scale) and the WFH X-ray Scale (WFH XR Scale) were inadequately sensitive to detect early changes in joints. New scales were developed based on suggested modifications of the existing scales and called the Haemophilia Joint Health Score (HJHS) and the International MRI Scales. The new scales were piloted. Concordance was measured by the intra-class correlation coefficient of variation. Reliability of the HJHS was excellent with an inter-observer co-efficient of 0.83 and a test-retest value of 0.89. The MRI study was conducted using both Denver and European scoring approaches; inter-reader reliability using the two approaches was 0.88 and 0.87; test-retest reliability was 0.92 and 0.93. These new PT and MRI scales promise to improve outcome assessment in children on early preventive treatment regimens.

Participants in an international conference on prophylactic therapy for severe haemophilia developed a consensus summary of the findings and conclusions of the conference. In the consensus, participants agreed upon revised definitions for primary and secondary prophylaxis and also made recommendations concerning the need for an international system of pharmacovigilance. Considerations on starting prophylaxis, monitoring outcomes, and individualizing treatment regimens were discussed. Several research questions were identified as needing further investigation, including when to start and when to stop prophylaxis, optimal dosing and dose interval, and methods for assessment of long-term treatment effects. Such studies should include carefully defined cohorts, validated orthopaedic and quality-of-life assessment instruments, and cost-benefit analyses.

Summary. Published retrospective reports from France, the Netherlands and Sweden were analysed for data relating to the long-term outcomes (primarily the development of arthropathy) of three regimens for the management of severe haemophilia: on-demand treatment, intermediate-dose prophylaxis and high-dose prophylaxis. The mean annual consumption of factor concentrate was also compared. These data indicate that both prophylaxis regimens resulted in significantly improved long-term outcomes, as assessed by pain, clinical and radiological assessment scores. At the same time, the most recently reported annual factor consumption levels of these young adult patients are comparable in the on-demand and intermediate-dose prophylaxis cohorts, suggesting that the improvement in long-term clinical outcomes and reduced risk of arthropathy may lead to reduced factor consumption in adult patients who received early prophylactic therapy.

Summary. Health-related quality of life (HRQoL) is increasingly used as an outcome parameter in haemophilia treatment. Currently, only generic HRQoL instruments are used, as disease-specific instruments for haemophilia are not available. The most widely used generic instruments are the descriptive SF-36 questionnaire and the EQ-5D questionnaire for assessment of utilities, ie preference-based HRQoL. Results of both instruments show significant correlation. All haemophilia prophylaxis studies using HRQoL as an outcome report a decreased HRQoL compared with the general population, a positive effect of prophylactic treatment and a negative effect of age. Generic instruments for measuring HRQoL are able to pick up differences between groups of patients with haemophilia and enable us to make comparisons across diseases. However, in order to establish the optimal treatment strategy for severe haemophilia, further information is needed on the long-term effects of different strategies on HRQoL. In addition, haemophilia-specific HRQoL instruments should be developed in order to provide detailed information for adjustment and evaluation of treatment in individual patients.

AAFACT, a monoclonal purified, solvent/detergent treated human plasma-derived coagulation factor VIII concentrate obtained from plasma of voluntary, non-remunerated blood donors, is manufactured and marketed in the Netherlands by Sanquin Plasma Products since 1995. In a postmarketing surveillance study, 70 previously treated haemophilia A patients were included (73% severe, 14% moderate and 13% mild haemophilia A). Most of these patients were followed during 4 years for the appearance of adverse events, possible transmissions of blood-borne viruses and the occurrence of antibodies against FVIII. The efficacy of treatment was determined in each patient by the in vivo recovery of FVIII. During this study, only six adverse events, possibly related to the use of AAFACT, were reported. None of these were indicated as serious. Transmissions of HIV, HAV, HBV and HCV in the seronegative patients have not been observed. In none of the patients, inhibitors to FVIII were detected. The in vivo recovery of FVIII during this study was not different from the in vivo recovery observed in eight patients during the preregistration study. There was a correlation of in vivo recovery with age and body weight. From these results, we conclude that the clinical usage of this human plasma-derived FVIII product is efficient and safe.

A multicentre study was performed in Sweden and the Netherlands, comparing effects of two prophylactic regimens in 128 patients with severe haemophilia, born 1970-90. 42 Swedish patients (high-dose prophylaxis), were compared with 86 Dutch patients (intermediate-dose prophylaxis). Patients were evaluated at the date of their last radiological score according to Pettersson. Annual clotting factor consumption and bleeding frequency were registered for a period of three years before evaluation. Patients in the high-dose group were younger at evaluation (median 15.2 vs. 17.9 years), started prophylaxis earlier (median 2 vs. 5 years), and used 2.19 times more clotting factor kg-1 year-1. Patients treated with high-dose prophylaxis had fewer joint bleeds (median 0.3 year-1 vs. 3.3 year-1) and the proportion of patients without arthropathy as measured by the Pettersson score was higher (69% vs. 32%), however, the age-adjusted difference in scores (median 0 points vs. 4 points) was small and at present not statistically significant. Clinical scores and quality of life were similar. These findings suggest that, compared with intermediate-dose prophylaxis, high-dose prophylaxis significantly increases treatment costs and reduces joint bleeds over a period of 3 years, but only slightly reduces arthropathy after 17 years of follow-up.

In a multinational working group, an instrument (Haemo-QoL) to assess quality of life in children/adolescents with haemophilia and their parents has been developed. In co-operation with haemophilia treatment centres in six European countries, approximately 10 children/adolescents with haemophilia per country and their parents were asked to participate in the pilot-testing. Both self-reported and parent-reported questionnaires were provided for two age-groups of children (4-16 years). Medical data was collected from physicians from patient files. Answers to open questions from participants (58 children and 57 parents) confirmed the content of 116 of the preliminary items. Cognitive debriefing revealed that the majority of the Haemo-QoL was rated favourably, but 29 questions were recommended to be omitted and several items to be reformulated. Preliminary psychometric testing of the revised 77 item questionnaire in the same sample showed acceptable reliability and validity, which will be examined in a subsequent study with a larger patient sample.

A cohort study was performed to assess adherence to early prophylactic therapy and its effects on outcome in 49 patients with severe haemophilia born 1970-1980. Median age at start of prophylaxis was 5.5 years. The majority (69%) of patients interrupted prophylactic treatment one or more times of their own accord (median total interruption 2.2 years). Patients who discontinued prophylaxis at any point tended to have more arthropathy as measured by the Pettersson scale (median 8 points versus 4 points). One-third of these patients interrupted prophylaxis for longer periods and had permanently stopped taking prophylaxis at a mean age of 20.1 years (mean +/- SD duration 4.1 +/- 4 years) and consequently experienced 5.4 +/- 3.4) joint bleeds per year. This subgroup could be identified by a predictive score based on age at start of prophylaxis, weekly dose of prophylaxis, and joint bleed frequency on prophylaxis. In conclusion, while on prophylaxis, more than two-thirds of patients with severe haemophilia try to discontinue treatment, resulting in slightly more arthropathy. One-third of these patients permanently discontinue prophylaxis in adulthood, while maintaining a low number of joint bleeds.

A cohort study was performed among 214 patients with severe haemophilia, born 1944-1994, to describe changes in treatment over the last 3 decades and its effects on clotting factor consumption and haemophilic arthropathy. Data on treatment strategy, clotting factor consumption, and outcome were collected for 3567 patient years (from 1972 to 1998), and 493 Pettersson scores were analysed. Median follow up was 17 years (range 6-27 years), and median age in 1998 was 27.6 years. Since 1965, replacement therapy, prophylaxis, and home treatment have been used and treatment intensified. Over the last 3 decades, annual clotting factor consumption increased by 260%, for both prophylactic and on-demand treatment. Annual clotting factor consumption kg-1 increased during childhood and appeared to stabilize in early adulthood for patients born 1965-79, who were treated with early replacement therapy or early prophylaxis. In contrast, clotting factor consumption increased continuously for patients born before 1965, who had had no access to replacement therapy during the early years of their life. The annual number of joint bleeds decreased over the years. Arthropathy as measured by the Pettersson score generally became apparent around the age of 15 years and was lowest in patients treated with primary prophylaxis. In conclusion, clotting factor consumption has increased and haemophilic arthropathy has decreased due to the intensification of treatment for severe haemophilia over the last 3 decades. Annual clotting factor consumption stabilizes in adulthood for patients who receive early intensive treatment.

It has been suggested that ultrapure clotting factor products carry a greater risk for inhibitor development in patients with haemophilia. We compared the incidence of inhibitors in 59 previously untreated patients (PUPs) with severe haemophilia (endogenous factor VIII < 0.01 U L-1) A, who were initially treated with cryoprecipitate or intermediate purified products, with that in 22 patients exclusively treated with monoclonally purified and recombinant factor VIII. Persistent inhibitors were those with 1 Bethesda unit per mL or more, on more than one occasion, combined with a decrease in recovery. Incidences of persistent inhibitors were 17% (10/59) for patients who were treated with cryoprecipitate or intermediate-purity products and 9% (2/10) for monoclonally purified and recombinant factor VIII. Transient inhibitors appeared to develop earlier during treatment with ultrapure products as compared to treatment with intermediate/low-purity products. In conclusion, ultrapure products appear not to carry a higher risk for inhibitor development.

A survey was made of the current status of treatment of haemophilic boys at 20 centres in 16 European countries and includes approximately 1500 of the estimated 6500 haemophiliacs in the participating countries. Many mild haemophiliacs are not seen, or seen infrequently, at haemophilia centres and this requires study. Nine of 18 centres provide continuous prophylaxis to 80-100% of their patients, five centres provide it to 55-80% and the remaining four centres to 15-40% of the boys. The median dose given was 6240 U kg-1 year-1 (range 3120-7800). Four centres administered only recombinant concentrates to children with severe haemophilia A, while seven centres administered recombinant concentrates to 75-90% and the remaining centres to less than 50% of the boys (two centres

The aim of this pilot study was to examine the usefulness of the Dutch version of the Arthritis Impact Measurement Scales 2 (D-AIMS2)in assessing the health status of Dutch individuals with haemophilia. Sixty-eight individuals with mild, moderate, and severe haemophilia attending our clinic for their annual check-up participated. They first completed the Canadian Occupational Performance Measure (COPM). The D-AIMS2 was filled in afterwards at home. With the COPM, individuals rated their specific problematic activities of daily life (ADL), as well as the severity and importance of each problem. The D-AIMS2 is a comprehensive, self-administered questionnaire that evaluates functional health status. Fifty-seven individuals completed and returned the D-AIMS2. Reliability analysis demonstrated good internal consistency for the scales (Cronbach's alpha=0.76-1.00), as well as for the components (alpha=0.80-0.88), except for the component 'social interaction' (alpha=0.44). Criterion validity of the D-AIMS2 was assessed by comparison with COPM outcomes; 80% of the problematic ADLs were included in the questionnaire, 20% were missing. Correlations between the D-AIMS2 components 'physical health' and 'symptoms' with predicted scores of those individuals by a highly experienced physiotherapist (r=0.63 and 0.53, respectively) substantiated its concurrent validity. Based on these results we concluded that the D-AIMS2, with minor adjustments, can be an appropriate tool for assessing the health status of Dutch haemophilia patients.

INTRODUCTION: Access to treatment and especially to long-term regular replacement treatment with clotting factor concentrates (prophylaxis) have caused dramatic contrasts in the clinical picture between haemophilia populations. An individual patient with severe haemophilia age 20 years can have normal joints or can be severely crippled and unable to work. Assessment of outcome in a standardized way has therefore become essential. AIM: Discuss the relevance and utility of the different outcome assessment tools in patient groups with different access to treatment. METHODS: In the last decade new outcome assessment tools specific for haemophilia have been developed that measure all aspects of health according to the International Classification of Functioning, Disability and Health (ICF) model. These tools are directed at assessing the clinical and radiological status of joints as well as overall functioning, such as participation and psychosocial aspects, evaluating overall health-related quality of life (HRQOL). For deciding which tools to use in clinical practice or research, one needs to consider the specific context with regard to disease burden, healthcare environment and socioeconomic background of the patients being evaluated. CONCLUSION: Prospective systematic assessment of outcome in haemophilia and related bleeding disorders is important. Based upon recent literature a critical appraisal of outcome tools is described.

Treatment of previously untreated patients (PUPs) with severe haemophilia A is complicated by the formation of inhibitors. Prediction of PUPs with high risk is important to allow altering treatment with the intention to reduce the occurrence of inhibitors. An unselected multicentre cohort of 825 PUPs with severe haemophilia A (FVIII

Port-A-Caths have been used increasingly in children with severe haemophilia. In non-inhibitor patients where Port-a-Caths were used to facilitate long-term prophylaxis, the infection rate is rather low and ranges in the various studies from 0 to 29%, with a median follow-up time of about 27 months. Patients that received the Port-A-Cath for the induction of immune tolerance (inhibitor patients) have a high infection rate of 50% to 83%. Although this percentage is high, good venous access is extremely important, especially in this group. The number of both inhibitor and non-inhibitor patients in the studies are very small, and a prospective survey is important to obtain more adequate data.