Prophylaxis in haemophilia patients with inhibitors

Radiosynovectomy for the Treatment of Chronic Hemophilic Synovitis: An Old Technique, but Still Very Effective

A radiosynovectomy (RS) should be indicated when recurrent articular bleeds related to chronic hemophilia synovitis (CHS) exist, established by clinical examination, and confirmed by imaging techniques that cannot be constrained with hematological prophylaxis. RS can be performed at any point in life, mainly in adolescents (>13−14 years) and adults. Intraarticular injection (IAI) of a radioactive material in children might be arduous since we need child collaboration which might include general anesthesia. RS is our initial option for management of CHS. For the knee joint we prescribe Yttrium-90, while for the elbow and ankle we prescribe Rhenium-186 (1 to 3 IAIs every 6 months). The procedure is greatly cost efficient when compared to surgical synovectomy. Chemical synovectomy with rifampicin has been reported to be efficacious, inexpensive, simple, and especially practical in developing countries where radioactive materials are not easily available. Rifampicin seems to be more efficacious when it is utilized in small joints (elbows and ankles), than when utilized in bigger ones (knees). When RS and/or chemical synovectomy fail, arthroscopic synovectomy (or open synovectomy in some cases) should be indicated. For us, surgery must be performed after the failure of 3 RSs with 6-month interims. RS is an effective and minimally invasive intervention for treatment of repeated articular bleeds due to CHS. Although it has been published that the risk of cancer does not increase, and that the amount of radioactive material used in RS is insignificant, the issue of chromosomal and/or deoxyribonucleic acid (DNA) changes remains a concern and continued surveillance is critical. As child and adulthood prophylaxis becomes more global, RS might become obsolete in the long-term.

Physician preferences for medication attributes for the prophylactic treatment of patients with severe haemophilia A with inhibitors to factor VIII

Prophylaxis may be beneficial for patients with severe haemophilia A who have developed inhibitors to factor VIII. The aim of this study was to determine physicians' preferences for medication attributes in the prophylactic treatment of this patient population. Haematologists from Europe (EU) and the United States (US) participated in a discrete choice exercise to explore their preferences for medication attributes (efficacy, cost, scientific evidence, dosing frequency and administration time) associated with prophylaxis for severe haemophilia A in patients with inhibitors to factor VIII. Physicians' preferences for medication attributes were assessed through completion of 25 trade-off tasks that included a choice between two hypothetical medications each comprised of one randomized level of each medication attribute. Participants also completed a sociodemographic questionnaire. Data were analysed using a random effects logit model. Participants (N = 36: US = 19; EU = 17) were 80.6% men, had a mean of 19.8 years (SD ± 8.1) [range 6-35] of practice experience. The physicians treated an average of 5.7 (± 5.5) patients with severe haemophilia A and inhibitors per month and reported treating 36.2% of these patients prophylactically. The most important medication attributes for prophylactic treatment were efficacy [Relative Importance (RI) = 35.0%] and scientific evidence (RI = 34.1%), whereas treatment cost (12.0%), dosing frequency (10.8%) and administration time (8.2%) were less important. Results were similar across the EU and US. Efficacy and scientific evidence are the primary considerations for physicians' choice of prophylactic medications for use in this patient population.

Haemophilia imaging: a review

Haemophilia disorders are characterised by a blood coagulation anomaly leading to prolonged and excessive bleeding. Imaging provides an essential role in the investigation of both the musculoskeletal and the non-musculoskeletal complications of haemophilia. Our institution is home to a large tertiary referral centre for haemophilia treatment. Using our broad experience, we present a multi-modality pictorial review of the musculoskeletal manifestations of haemophilia, including haemophilic arthropathy, intra-muscular haemorrhage and haemophilic pseudotumour. The main imaging features of haemophilic arthropathy are described, including synovial hypertrophy, haemosiderin deposition, sub-chondral cyst formation and loss of joint space.

Prophylaxis in 10 patients with severe haemophilia A and inhibitor: different approaches for different clinical situations

The effect of bypassing agents is not as predictable as replacement therapy with the deficient factor in inhibitor patients. Consequently, these patients have more levels of arthropathy than patients without inhibitors. Prophylaxis for inhibitor patients has gained attention over the last decade and some papers have reported that bypassing agents could work in the prevention of arthropathy. However, there is a lack data to support any specific agent or regimen or even to recommend their use in different clinical conditions. We report ten patients with haemophilia A and inhibitors treated prophylacticaly with bypassing agents (5 with FEIBA and 5 with NovoSeven). The variable conditioning the choice of one agent or the other was the intention to initiate of immune tolerance induction therapy (ITI) in the future. In 8/10 patients (4 in FEIBA group and 4 in rFVIIa group) there was a decrease of bleeding episodes while 9/10 maintained or increased their joint range of motion (ROM). In the rFVIIa prophylaxis group, prophylaxis can be considered primary since all of them had had less than one joint bleed before prophylaxis. Economic analysis showed that prophylaxis is an expensive treatment. In our experience both agents seem to be safe and effective in reducing the number of bleeds in patients with inhibitors. The anamnestic response provoked by FEIBA could be an issue while awaiting a decline in titres before ITI can be initiated and so rFVIIa may be the best option for prophylaxis in patients with inhibitors who have not yet begun ITI.

Inhibitor development in haemophilia B: an orphan disease in need of attention

Factor IX (FIX) inhibitors develop in 1.5-3% of haemophilia B patients. Due to its low incidence compared with that in haemophilia A, few comparable data exist on host and treatment-related risk factors, and immunological processes associated with FIX inhibitor development. Moreover, the safety and efficacy of bypass therapy as well as the outcome predictors of successful inhibitor eradication have been poorly characterised. The lack of a useful evidence-based approach to the diagnosis and management of FIX inhibitors complicates their significant morbidity due to the frequency of allergic reactions that often herald antibody development. This review discusses what is currently known about the epidemiology, natural history and immunology of anti-FIX antibody development. It addresses several special considerations in the approach to the treatment of bleeding and inhibitor eradication. A case is made for moving forward with an integrated international collaboration for the further study of the nature and treatment of this problem.