UKHCDO guidelines on the management of HCV in patients with hereditary bleeding disorders 2011

Chronic HCV infection continues to be of significant clinical importance in patients with hereditary bleeding disorders. This guideline provides information on the recent advances in the investigation and treatment of HCV infection and gives GRADE system based recommendations on the management of the infection in this patient group.

Development of a rapid DNA screening procedure for the Factor V Leiden mutation

Aim-To develop a rapid, simple and highly specific DNA screening procedure based on the amplification refractory mutation system (ARMS) to detect the Leiden mutation in whole blood.Methods-ARMS PCR amplification primers with additional mismatches at either -2 or -3, which greatly improves specificity, were constructed to detect the normal Factor V gene and the Leiden mutation in whole blood samples from patients with abnormal clotting results.Results-Construction of ARMS primers with either an additional mismatch at -2 or -3 at the 3' end of the primer could be used to detect the Leiden mutation in 0.5 mu1 whole blood in under three hours. Primers destabilised at position -3 could be used at a lower annealing temperature, which gave greater sensitivity and are now routinely used. A control set of primers was included in the same reaction to act as a positive control.Conclusions-This rapid and specific assay for the factor V Leiden mutation is a useful addition to the investigation of patients with or at risk from thrombovascular disease.

Economic evaluation of dabigatran etexilate for the prevention of venous thromboembolism in patients aged over 75 years or with moderate renal impairment undergoing total knee or hip replacement

Oral dabigatran etexilate is indicated for the prevention of venous thromboembolism (VTE) in patients undergoing total knee replacement or total hip replacement. We investigated the cost-effectiveness of the 150 mg once daily (od) dose recommended for patients aged over 75 or with moderate renal impairment, from a United Kingdom National Health Service perspective. Dabigatran etexilate was compared with subcutaneous enoxaparin 40 mg od, using a decision model. Risks for VTE and bleeding were derived from subgroup analyses of the phase III trials. Dabigatran etexilate was less costly than enoxaparin; cost savings varied from pound62 to pound274 (base-case analyses) and were primarily due to differences in administration costs. Results were robust across a range of sensitivity analyses. Dabigatran etexilate 150 mg od is cost saving compared with enoxaparin 40 mg od in patients aged over 75years and in patients with moderate renal impairment, with comparable efficacy and safety.

Challenges and controversies in haemophilia care in adulthood

Overall life expectancy and quality of life among persons with haemophilia have increased in recent years, primarily because of the advances in factor replacement therapy and better treatment of infectious diseases. Older haemophilic patients now face aging co-morbidities that are common in the general male population, such as cardiovascular or metabolic diseases, prostate hypertrophy and hepatic, prostate and other cancers. The prevalence of cardiovascular disease and incidence of vascular events among older haemophilic patients can be expected to increase and haemophilic patients may become prone to some cardiovascular risk factors, warranting preventative measures. The treatment of long-term complications of hepatitis C virus infection such as liver cirrhosis and hepatic cancer can be expected to be required in a large portion of the older haemophilia population for some years to come. Appropriate antiviral treatment and close monitoring for possible disease advancement will constitute an important part of routine medical care, and special considerations may be appropriate in conjunction with invasive procedures, chemo- or radiotherapy. At the moment, hard data on which to base the management of these conditions are largely lacking, but can be expected to increase dramatically in the coming decades. In the meantime, the ageing population of haemophilia patients should be offered the same comprehensive health care offered to the general population, which may require a restructuring of health care delivery.

Effect of setting, monitoring intensity and patient experience on anticoagulation control: a systematic review and meta-analysis of the literature

OBJECTIVES

To investigate the relationship between time spent in the recommended target International Normalised Ratio (INR) range and the setting and intensity of anti coagulant monitoring, in both treatment-experienced and treatment-naive atrial fibrillation (AF) patients receiving oral anticoagulation (OAC) therapy for the prevention of ischaemic stroke.

RESEARCH DESIGN AND METHODS

Systematic review of published studies on participants with atrial fibrillation on anticoagulation therapy. We compared frequent monitoring (well-controlled, according to a strict protocol) versus infrequent monitoring (frequency representative of routine clinical practice), specialised care versus usual care, and naive versus prior anticoagulant use. Meta-analysis was performed using a random effects model.

RESULTS

36 studies were included, 22 (primary data) of AF patients managed in line with the consensus guidelines target INR range of 2.0-3.0, and 14 studies (secondary data) of mixed patient groups, including AF, with an INR target of 2.0-3.5. Both data sets were combined for sensitivity analysis. Pooled mean time in INR range was 59.1% (95% CI: 55.5, 62.8%) and 64.3% (95% CI: 60.5, 68.0%) for infrequent monitoring and frequent monitoring, respectively. Significantly more time was spent in range in specialist care settings compared to usual care: +11.3% (95% CI: 0.1-21.7%). Naive OAC users spent less time in range 56.5% (95% CI: 45.5-67.5%) than existing users 61.2% (95% CI: 57.2-65.2%). All of these differences were found to be significant in the sensitivity analyses.

CONCLUSIONS

INR control is variable and dependent on monitoring intensity and duration of anticoagulant therapy.

Tyr346-->Cys mutation results in factor VIII:C assay discrepancy and a normal bleeding phenotype - is this mild haemophilia A?

Patients with mild haemophilia A may have a discrepancy in the factor VIII (FVIII) level when measured with a one-stage assay (FVIII:C1) compared with a two-stage assay (FVIII:C2). This discrepancy usually results in the one-stage level being higher than the two-stage level. A F8 mutation resulting in a Tyr346-->Cys substitution within the a1 interdomain region has been described which results in the converse assay discrepancy. We report four individuals (three families) who have this mutation. Mean FVIII:C1 level was 25 IU dL(-1) compared with a mean FVIII:C2 level of 63 IU dL(-1). These individuals had presented opportunistically and did not have a clinically significant bleeding disorder. The bleeding phenotype correlated with the two-stage assay result rather than the one-stage result. FVIII replacement therapy does not appear to be required for these individuals.

Should prophylaxis be used in adolescent and adult patients with severe haemophilia? An European survey of practice and outcome data

A survey of 21 haemophilia doctors, throughout Europe, who care for a total of approximately 5000 patients with bleeding disorders addressing practice and opinions regarding prophylaxis in patients aged 16-24 years and adults aged over 50 years, is presented. The outcome of adolescent patients who reduced or stopped prophylaxis was recorded. Eighteen of 19 respondents would consider modification of established prophylaxis in the adolescent age group, principal considerations being avoidance of risks of further concentrate exposure, predicted poor compliance and treatment costs. The preferred age for modification was 16-20 years, but there was very little consensus on the particular prophylactic regime recommended. Approximately, half of a cohort of 218 patients with severe haemophilia successfully reduced or stopped prophylaxis when they reached adolescence. Only 26 of 92 (28%) of the patient cohort who stopped prophylaxis, required reintroduction of a prophylactic regime and 12 of 59 (20%) of those who reduced the intensity of prophylaxis had to reintroduce a more intensive regime. A majority of respondents would consider starting prophylaxis in those over 50 years. There was no consensus as to indications for this practice or the nature of the prophylaxis protocol. We conclude that there is an absence of consensus on the management of patients with severe haemophilia, as they pass through adolescence and young adulthood, and reach the age of 50. Aggregate outcome data suggest a significant proportion of patients in the 18-22 years age range may be able to reduce or stop prophylaxis. A substantial number of older patients are on prophylaxis.

European Study on Orthopaedic Status of haemophilia patients with inhibitors

Development of inhibitors against factor VIII (FVIII) or factor IX (FIX) in haemophilia patients is one of the most serious complications of repeated exposure to replacement therapy and has major clinical and economic consequences. To evaluate the relationship between inhibitor status of haemophilia patients and their quality of life (QoL) and degree of arthropathy and to compare the orthopaedic status of patients with/without inhibitors. An observational, cross-sectional, case control study enrolling: group A (n = 38), males aged 14-35 years, with severe congenital haemophilia A or B who had inhibitors against FVIII/FIX >5 years; group B (n = 41), as group A, but aged 36-65 years and group C (n = 49), as group A, but without inhibitors. Socio-demographics: medical history, clinical characteristics and QoL were assessed. In groups A and B, 16% and 27% were hospitalized for orthopaedic procedures vs. 4% in group C. Patient mobility was also severely reduced in groups A and B, with 24% and 22% using wheelchairs vs. 4% in group C, and 50% and 51% needing a walking aid vs. 29% in group C. Significantly more joint pain was reported by patients in group A vs. those in group C; clinical/radiological orthopaedic scores were also worse in group A vs. group C. Significantly more joint abnormality was reported by patients in group A vs. group C. The burden of orthopaedic complications and the impact on QoL are more severe in haemophilia patients who have developed inhibitors than in those without inhibitors.

Pregnancy outcome in Factor XI deficiency: incidence of miscarriage, antenatal and postnatal haemorrhage in 33 women with Factor XI deficiency

Pregnancy complications in women with Factor XI deficiency were assessed in this retrospective analysis. All nonnulliparous women registered with Factor XI deficiency in the East Midlands region were included. Each woman was classified into 'bleeder' or 'nonbleeder'. Rates of antenatal and postnatal bleeding and miscarriage rate were recorded. A total of 33 women had 105 pregnancies. Pregnancy and delivery was uneventful in 70% of the cases. Postpartum haemorrhage (PPH) appears increased in women with a 'bleeding' phenotype with a highly significant difference between 'bleeders' and 'nonbleeders' (relative risk [RR] 7.2; CI 1.99-25.9). Miscarriage rate appeared unchanged. We conclude that PPH is increased in a subgroup with a bleeding phenotype. Larger studies are needed to define the underlying factors.

Clinical implications of emerging pathogens in haemophilia: the variant Creutzfeldt-Jakob disease experience

The impact of variant Creutzfeldt-Jakob disease (vCJD) on the clinical practice of haemophilia in the UK is coloured by the haemophilia community's experience of hepatitis C virus and human immunodeficiency virus (HIV) transmission via plasma-derived therapies in the 1980s, when the delay in recognizing and acting on the potential risks cost many patients their lives and left others to manage another chronic disease. This crisis prompted organisations such as the United Kingdom Haemophilia Centre Doctors' Organisation to advocate for the introduction of haemophilia therapies that would not be susceptible to contamination with blood-borne pathogens. After the identification of vCJD in 1996, a number of public health measures were taken in response to a government-sponsored vCJD risk assessment, and following reports of transfusion-transmission of vCJD, additional guidelines have been developed to prevent person-to-person transmission, some of which may impact the quality and availability of medical and surgical care. Variant CJD has had a significant negative effect on the UK haemophilia community, shaking patient confidence in the therapies they have received over the last 21 years, affecting the quality of care and creating the risk of stigmatizing the community as it was in the 1980s. As with HIV and vCJD, emerging blood-borne infectious agents will likely affect blood and blood-derived therapies well before we become aware of its presence. As a result, only therapies with the lowest level of risk should be used for care of patients with haemophilia.

Management of acute bleeding in a patient with congenital afibrinogenaemia

Congenital afibrinogenaemia is a rare bleeding disorder characterized by absence of fibrinogen and varying bleeding tendency. Treatment with fibrinogen concentrates is considered to be the best choice for afibrinogenaemic patients who experience bleeding. We report the case of a 22-year-old Greek patient who presented with large muscular haematomas and was treated with fibrinogen concentrates. The efficacy of this treatment and the problems that arose during his hospitalization are being discussed.

Spontaneous superficial venous thrombophlebitis: does it increase risk for thromboembolism? A historic follow-up study in primary care

OBJECTIVE

To determine the risk of arterial and venous complications after a spontaneous superficial venous thrombophlebitis (SVTP) in the leg in a general practice population.

STUDY DESIGN

Retrospective cohort study (LOE: 2b [CEBM]). Exposure consisted of the diagnosis of SVTP of the lower limbs on an index date. The exposed cohort was compared with an (unexposed) cohort of practice-, age-, and sex-matched controls without SVTP.

POPULATION

Patients with spontaneous SVTP in the leg were identified through diagnostic coding in the medical registers of 40,013 patients, enlisted with 5 health centers in Amsterdam, The Netherlands.

OUTCOMES

Primary outcomes were deep venous thrombosis (DVT), pulmonary embolism (PE), acute coronary events, or ischemic stroke over a 6-month follow-up period. Odds ratios (OR) were used to quantify the associations between SVTP and outcome events.

RESULTS

No statistically significant odds ratios were found for PE, coronary events or stroke. DVT was the only primary outcome to show a significant relationship. DVT occurred in 2.7% of all SVTP patients as compared with 0.2% in the controls (OR=10.2; 95% confidence interval [CI], 2.0-51.6). When controlling for prior history of DVT, the OR decreased to 7.1 and the confidence interval crossed 1.0 (95% CI, 0.9-65.6).

DISCUSSION

Spontaneous SVTP in the leg is a risk factor for DVT, but is less predictive in patients with prior DVT. Although effective treatments for the prevention of DVT are available, the absolute risk is too low to advocate prophylaxis in a general practice population. More research on prophylaxis is needed to stratify these patients at risk.

ESOS: a European study on the orthopaedic status of patients with haemophilia and inhibitors

Published studies highlight the paucity of data relating to orthopaedic health and quality of life in haemophilia patients with inhibitors. A European Study on the Orthopaedic Status of Patients with Haemophilia and Inhibitors (ESOS) has been set up to address this lack of data. This cross-sectional retrospective study aims to enrol 400 patients from 50 sites in nine European countries. The primary outcome measure of the study is the burden of orthopaedic complications in patients with severe haemophilia and inhibitors. The data that will be generated should demonstrate the high level of arthropathy in haemophilia patients with inhibitors and show the need to focus on improving orthopaedic health in this rare, but particularly vulnerable, patient population.

A framework for genetic service provision for haemophilia and other inherited bleeding disorders

This framework document offers guidance to patients, doctors, nurses, laboratory scientists, funders and hospitals on the provision of clinical and laboratory genetic services for haemophilia. With recent advances in molecular laboratory techniques it is now possible to give the vast majority of individual patients and family members very reliable genetic information. To enable these genetic data to be used for both the optimal treatment of patients with inherited bleeding disorders and for appropriate reproductive decisions in carriers, there needs to be a clear and robust framework for systematically acquiring the necessary clinical, personal, family and laboratory information upon which decisions can be made. This document provides guidance on the range and standards of clinical and laboratory genetic services which should be offered to patients and their families. Included are arrangements for genetic counselling and testing (including consent and confidentially issues), management of early pregnancy, standards for laboratory genetic services, as well as advice on data storage, security and retrieval.

Mutation analysis in 51 patients with haemophilia A: report of 10 novel mutations and correlations between genotype and clinical phenotype

We report the results of genetic analysis on a series of 51 patients attending this Haemophilia Comprehensive Care Centre. The most common cause of severe haemophilia A--the factor VIII intron 22 inversion was detected in eight families and the factor VIII intron 1 inversion in three families. Mutation analysis was carried out on the remaining patients by nucleotide sequencing of genomic DNA after screening with conformation-sensitive gel electrophoresis (CSGE) or denaturing high-performance liquid chromatography (dHPLC). A total of 27 different FVIII non-inversion mutations were detected. Severe haemophilia was associated with 12 null mutations (six nonsense, six frameshift) and four missense mutations. A further 11 different missense mutations were associated with moderate or mild disease. To our knowledge, six null mutations [1950del 4(tttg), 3270-75insA, 4416del 10, 6735-38delA, W1029X, Y1792X] and four missense mutations (E1682K, M1947V, P2048L, P2143L) have not been previously published. Each novel missense mutation occurred at a highly conserved residue, no other candidate mutation was detected on screening the entire coding region of the FVIII gene and they were not detected in a screen of individuals without haemophilia A. The genotype-phenotype correlations of the FVIII mutations detected will be discussed.

The rare coagulation disorders - review with guidelines for management from the United Kingdom Haemophilia Centre Doctors' Organisation

The rare coagulation disorders are heritable abnormalities of haemostasis that may present significant difficulties in diagnosis and management. This review summarizes the current literature for disorders of fibrinogen, and deficiencies of prothrombin, factor V, FV + VIII, FVII, FX, the combined vitamin K-dependent factors, FXI and FXIII. Based on both collective clinical experience and the literature, guidelines for management of bleeding complications are suggested with specific advice for surgery, spontaneous bleeding, management of pregnancy and the neonate. We have chosen to include a section on Ehlers-Danlos Syndrome because haematologists may be consulted about bleeding manifestations in such patients.