Hemophilia and related bleeding disorders: a story of dismay and success

Recombinant porcine factor VIII: Lessons from the past and place in the management of hemophilia A with inhibitors in 2021

The most serious complication of factor VIII (FVIII) replacement therapy is the occurrence of anti-FVIII alloantibodies that can strongly reduce or abolish the effect of human FVIII products. Bypassing agents to control bleeding episodes are recommended for these patients, but their efficacy is difficult to predict and monitor. FVIII products derived from porcine plasma had an important role in the treatment of hemophilia A for 50 years, from 1954 to 2004. Indeed, porcine FVIII could achieve hemostasis in patients in whom human FVIII products were ineffective. A recombinant porcine FVIII product is now available. This highly purified protein has the same biochemical and hemostatic properties, but much lower risks of infection and toxicity compared with plasma-derived porcine FVIII. The product is licensed in the United States and Europe for the treatment of acquired hemophilia A. However, this recombinant molecule could also be of clinical interest for people with inherited hemophilia A and inhibitors, particularly for the management of bleeding episodes in people receiving emicizumab as prophylactic treatment in the absence of anti-porcine FVIII antibodies.

Haemophilia: factoring in new therapies

Haemophilia is an inherited bleeding disorder in which the haemostatic defect results from deficiency of coagulation factor VIII (FVIII) in haemophilia A or factor IX (FIX) in haemophilia B. Traditional treatments for haemophilia have largely worked by directly replacing the missing coagulation factor, but face challenges due to the short half-life of FVIII and FIX, the need for frequent intravenous access and development of neutralising antibodies to coagulation factors (inhibitors). Recent advances in haemophilia therapy have worked to eliminate these challenges. Half-life extension of factor concentrates has lengthened the time needed between infusions, enhancing quality of life. Subcutaneous administration of therapeutics utilising alternative mechanisms to overcome inhibitors have expanded the options to prevent bleeding. Finally, initial successes with gene therapy offer a cautious hope for durable cure. In the present review, we will discuss currently available treatments, as well as highlight therapeutics in various stages of clinical development for the treatment of haemophilia A and B. In this review, we present therapies that are currently clinically available and highlight therapeutics that are in various stages of clinical development for the treatment of haemophilia A and B.

Inflammation, angiogenesis and sensory nerve sprouting in the synovium of bony ankylosed and not bony ankylosed knees with end-stage haemophilic arthropathy

INTRODUCTION

Clinical practice showed that patients with haemophilia (PwH) with bony ankylosed end-stage haemophilic arthropathy knees reported milder pain than those with not bony ankylosed knees.

AIM

To compare the differences in pain sensation and the histopathological differences in synovial samples of affected knee joints between PwH with bony ankylosed end-stage haemophilic arthropathy knees and those with not bony ankylosed knees.

METHODS

From January 2011 to December 2019, the synovial samples of knee joints were collected during total knee arthroplasty (TKA) surgery for end-stage haemophilic arthropathy. The visual analogue scale (VAS, 0-10) pain score was reviewed from the chart data of the patients. The thickness of the inner layer of the synovium in haematoxylin and eosin (H&E) staining sections was measured. The expression levels of Ki67, IL-1β, TNF-α, CD31, VEGF, NGF and PGP9.5 in the synovium were detected by immunohistochemistry (IHC) method.

RESULTS

Fifty-two end-stage haemophilic arthropathy knee synovial samples from 36 male PwH (34 type A and 2 type B) were collected. Fifteen knees had bony ankylosed (BA-group), and 37 were not bony ankylosed (Not-BA-group). The mean age of patients at TKA surgery of BA-group and Not-BA-group was 32 years (15) and 32 years (10), respectively (p = 0.824). Before TKA surgery, the mean VAS pain scores of patients in the Not-BA-group were significantly higher than those in the BA-group (p < 0.001). The mean thickness of the inner layer of the synovium, the mean rate of Ki67+ cells, the mean density of CD31+ vascular endothelial cells and the expression levels of IL-1β, TNF-α, VEGF and NGF in samples in the Not-BA-group was significantly higher than those in samples in the BA-group (p < 0.001, p = 0.02, p = 0.001, p = 0.117, p < 0.001, p = 0.003 and p = 0.008), respectively. The mean density of PGP9.5+ sensory neural fibres in the Not-BA-group was slightly higher than in the BA-group (p = 0.131). Linear regression analysis showed a significant positive correlation between the VAS pain score and indicators including the synovial thickness, the rate of Ki67+ cells, the expression level of IL-1β, TNF-α, VEGF, NGF and the densities of CD31+ vascular endothelial cells and PGP9.5+ nerve fibres (p < 0.05).

CONCLUSIONS

Worsened hypertrophic synovitis, angiogenesis and sensory nerve sprouting in the synovium may play a critical role in causing worse pain sensation in PwH with not bony ankylosed haemophilic arthropathy knees than in those with bony ankylosed knees.

Unique inflammatory signature in haemophilic arthropathy: miRNA changes due to interaction between blood and fibroblast-like synoviocytes

In haemophilia, the recurrence of hemarthrosis leads to irreversible arthropathy termed haemophilic arthropathy (HA). However, HA is a unique form of arthropathy in which resident cells, such as fibroblast‐like synoviocytes (FLS), come into direct contact with blood. Therefore, we hypothesized that FLS in HA could have a unique inflammatory signature as a consequence of their contact with blood. We demonstrated with ELISA and ELISPOT analyses that HA‐FLS expressed a unique profile of cytokine secretion, which differed from that of non‐HA‐FLS, mainly consisting of cytokines involved in innate immunity. We showed that unstable cytokine mRNAs were involved in this process, especially through miRNA complexes as confirmed by DICER silencing. A miRNOME analysis revealed that 30 miRNAs were expressed differently between HA and non‐HA‐FLS, with most miRNAs involved in inflammatory control pathways or described in certain inflammatory diseases, such as rheumatoid arthritis or lupus. Analysis of transcriptomic networks, impacted by these miRNAs, revealed that protein processes and inflammatory pathways were particularly targeted in LPS‐induced FLS, and in particular vascularization and osteoarticular modulation pathways in steady‐state FLS. Our study demonstrates that the presence of blood in contact with FLS may induce durable miRNA changes that likely participate in HA pathophysiology.

Antithrombin inhibition using nanobodies to correct bleeding in hemophilia

In this issue of EMBO Molecular Medicine, Barbon et al describe a new approach to rebalancing coagulation in patients with hemophilia (PWH) through targeted inhibition of anticoagulant antithrombin (AT) (Barbon et al, 2020). In contrast to previous studies that used RNA interference (RNAi) therapy to reduce AT levels (Sehgal et al, 2015; Pasi et al, 2017), the authors utilized llama‐derived single‐domain antibodies (sdAbs or nanobodies) to inhibit AT activity (Fig 1). These engineered sdAbs successfully restored thrombin generation in hemophilic plasma and corrected bleeding phenotype in a murine hemophilia model. Furthermore, long‐term AAV8‐mediated hepatic expression of the sdAb was well tolerated and associated with a sustained correction in bleeding in hemophilia A and B mice. Collectively, these exciting data uncover a novel AT‐targeting approach that may be useful as an alternative therapy for restoring normal hemostasis in PWH.

Gene therapy for hemophilia

Gene therapy offers the potential for a cure for patients with hemophilia by establishing continuous endogenous expression of factor VIII or factor IX (FIX) following transfer of a functional gene to replace the hemophilic patient's own defective gene. The hemophilias are ideally suited for gene therapy because a small increment in blood factor levels (≥5% of normal) is associated with significant amelioration of bleeding phenotype in severely affected patients. In 2011, the St. Jude/UCL phase 1/2 trial was the first to provide clear evidence of a stable dose-dependent increase in FIX levels in patients with severe hemophilia B following a single administration of adeno-associated viral (AAV) vectors. Transgenic FIX expression has remained stable at ∼5% of normal in the high-dose cohort over a 7-year follow-up period, resulting in a substantial reduction in spontaneous bleeding and FIX protein usage without toxicity. This study has been followed by unparalleled advances in gene therapy for hemophilia A and B, leading to clotting factor activity approaching normal or near-normal levels associated with a "zero bleed rates" in previously severely affected patients following a single administration of AAV vectors. Thus, AAV gene therapies are likely to alter the treatment paradigm for hemophilia A and B. This review explores recent progress and the remaining limitations that need to be overcome for wider availability of this novel treatment of inherited bleeding disorders.

Tranexamic acid may benefit patients undergoing total hip/knee arthroplasty because of haemophilia

BACKGROUND

The lower limb joints, including hip and knee, are the most commonly involved joints in haemophilic arthropathy. With a higher risk of transfusion, total hip and knee arthroplasty (THA and TKA) are still the first choice after failure of conservative treatment. In the present study, we aimed to analyze clinical outcomes and complications rate after total joint arthroplasty of the lower limbs using tranexamic acid (TXA) or not.

METHODS

Thirty-four patients with haemophilia A undergoing 24 TKA and 18 THA were evaluated in this retrospective study (No. 201302009). Based on using TXA or not, they were divided into either TXA (12 knees and 10 hips) or Non-TXA groups (12 knees and 8 hips). Total blood loss, intraoperative blood loss, total amount of FVIII usage, range of motion, inflammatory biomarkers, joint function, pain status, complication rate and patient satisfaction were assessed and compared at a mean follow-up of 68 months.

RESULTS

Usage of TXA can decrease not only the perioperative blood loss (p = 0.001), transfusion rate (p = 0.017) and supplemental amount of FVIII (p < 0.001) but also swelling ratio, surgical joint pain. Moreover, compared with non-TXA group, the patients in TXA group had a lower level of inflammatory biomarkers and better joint function.

CONCLUSION

The hemophiliacs treated with TXA had less perioperative blood loss, hidden blood loss, transfusion rate, a lower ratio of postoperative knee swelling, less postoperative joint pain, lower levels of inflammatory biomarkers and better joint function. Further studies need performing to assess the long-term effects of TXA in these patients.

Low Dose Prophylaxis in Hemophilia Care

Hemophilia is an inherited bleeding disorder which causes impaired blood clotting. The severity of disease depends on the type of Hemophilia, level of clotting factor concentrate (CFC), phenotypic heterogeneity and the development of inhibitors. The currently accepted standard of care of this disease is prophylaxis therapy (PT) with CFC. Prophylaxis therapy for Hemophilia is given in developed countries for the last few decades. On the contrary, episodic therapy (ET) is still the mode of treatment in middle and low income countries. ET is documented to have several potential risks such as increased bleeding rate, disability due to haemarthrosis, poor quality of life and increased chances of mortality. Several studies conducted in developed countries have confirmed the clinical efficacy of PT in Hemophilia treatment. Currently, there exist several challenges for implementation of this effective treatment in resource poor nations. Low dose prophylaxis (LDP) has been developed as a solution to minimize these challenges and to provide better care for subjects with Hemophilia from low resource countries. The impact of LDP was evaluated by several recent studies and the reported clinical outcomes seem to suggest an optimistic future for this line of therapy. Several themes related to Hemophilia care like inhibitor development, tolerance, pharmacokinetics of CFCs and cost-benefit analysis of different prophylaxis regimens are currently understood poorly. These distinct elements are highly relevant to assess the actual benefits of LDP regimen in a global scale.

Reaching Independence Through Forced Learning: Learning Processes and Illness Management in Parents of Children Affected by Hemophilia

Hemophilia is a complex condition to manage, especially for parents to newly diagnosed children. This grounded theory study explores parents' learning processes and illness management in daily life during the first year after the start of their child's treatment. Using a longitudinal qualitative design, eight parents of four children were interviewed repeatedly during 12 to 14 months. The core category, reaching independence through forced learning, reflected the parents' learning process and their experiences of the challenges during the first year after start of treatment. Incentives for learning were characterized by a longing to reach independence and regain control of one's life situation. The emerging key incentive for learning was a desire to become independent of health care professionals. Early home treatment reduced the impact of the illness, and by supporting parents in different ways during the learning process, health care professionals can promote the parents' trajectory toward independency.

Gene Therapy for Hemophilia

The best currently available treatments for hemophilia A and B (factor VIII or factor IX deficiency, respectively) require frequent intravenous infusion of highly expensive proteins that have short half-lives. Factor levels follow a saw-tooth pattern that is seldom in the normal range and falls so low that breakthrough bleeding occurs. Most hemophiliacs worldwide do not have access to even this level of care. In stark contrast, gene therapy holds out the hope of a cure by inducing continuous endogenous expression of factor VIII or factor IX following transfer of a functional gene to replace the hemophilic patient's own defective gene.

Current and emerging factor VIII replacement products for hemophilia A

Hemophilia A is a congenital X-linked bleeding disorder caused by coagulation factor VIII (FVIII) deficiency. Routine infusion of factor replacement products is the current standard of care; however, the development of alloantibodies against FVIII remains a challenge. The treatment of hemophilia has undergone major advances over the past century to improve safety, effectiveness, manufacturing, and convenience of factor products. Major recent advances in the treatment of hemophilia A include the emergence of extended half-life products, factor VIII orthologs, and gene therapy products. Extended half-life products were designed to decrease the frequency of infusions, but only modest half-life extension is achieved. Factor VIII orthologs featuring lower cross-reactivity with anti-FVIII antibodies may be less susceptible to inactivation by inhibitors. Meanwhile, gene therapy may potentially provide a cure for hemophilia A, thus abrogating the need for protein-based factor replacement. This review aims to discuss current and emerging FVIII replacement products for hemophilia A.

Gene Therapy for Coagulation Disorders

Molecular genetic details of the human coagulation system were among the first successes of the genetic revolution in the 1980s. This information led to new molecular diagnostic strategies for inherited disorders of hemostasis and the development of recombinant clotting factors for the treatment of the common inherited bleeding disorders. A longer term goal of this knowledge has been the establishment of gene transfer to provide continuing access to missing or defective hemostatic proteins. Because of the relative infrequency of inherited coagulation factor disorders and the availability of safe and effective alternative means of management, the application of gene therapy for these conditions has been slow to realize clinical application. Nevertheless, the tools for effective and safe gene transfer are now much improved, and we have started to see examples of clinical gene therapy successes. Leading the way has been the use of adeno-associated virus-based strategies for factor IX gene transfer in hemophilia B. Several small phase 1/2 clinical studies using this approach have shown prolonged expression of therapeutically beneficial levels of factor IX. Nevertheless, before the application of gene therapy for coagulation disorders becomes widespread, several obstacles need to be overcome. Immunologic responses to the vector and transgenic protein need to be mitigated, and production strategies for clinical grade vectors require enhancements. There is little doubt that with the development of more efficient and facile strategies for genome editing and the application of other nucleic acid-based approaches to influence the coagulation system, the future of genetic therapies for hemostasis is bright.

The Role of Angiogenesis in Haemophilic Arthropathy: Where Do We Stand and Where Are We Going?

Haemophilia is an inherited bleeding disorder that can lead to degenerative joint arthropathy due to recurrent bleeding episodes affecting the musculoskeletal system of the patient. The cause of bleeding can be either traumatic or spontaneous. The pathogenesis of haemophilic arthropathy is unclear as many factors like iron, inflammatory cytokines, and angiogenic factors contribute to this process. Blood into joints can deteriorate the bone to such an extent that the patient experiences pain, reduction of the range of movement, and deformity of the joint, conditions that could have a great impact on quality of life. Over the years, management of haemophilic arthropathy has changed. Nowadays, early diagnosis with high resolution imaging like magnetic resonance imaging along with application of prophylaxis regimens can reduce the extent of damage to the joints. However, not all haemophilia patients have access to these interventions as cost may be prohibitive for some of them. The need for new, easy, and cost-effective strategies with the ability to identify early changes could be beneficial and could make a difference in the management of haemophilic arthropathy. Understanding the mechanism of processes like angiogenesis in the mechanism of developing arthropathy could be innovative for these patients and could help in the detection of new early diagnostic and therapeutic markers.

Molecular Analysis of Factor VIII and Factor IX Genes in Hemophilia Patients: Identification of Novel Mutations and Molecular Dynamics Studies

Background

Hemophilias A and B are X-linked bleeding disorders caused by mutations in the factor VIII and factor IX genes, respectively. Our objective was to identify the spectrum of mutations of the factor VIII and factor IX genes in Saudi Arabian population and determine the genotype and phenotype correlations by molecular dynamics (MD) simulation.

Methods

For genotyping, blood samples from Saudi Arabian patients were collected, and the genomic DNA was amplified, and then sequenced by Sanger method. For molecular simulations, we have used softwares such as CHARMM (Chemistry at Harvard Macromolecular Mechanics; http://www.charmm-gui.org) and GROMACS. In addition, the secondary structure was determined based on the solvent accessibility for the confirmation of the protein stability at the site of mutation.

Results

Six mutations (three novel and three known) were identified in factor VIII gene, and six mutations (one novel and five known) were identified in factor IX gene. The factor VIII novel mutations identified were c.99G>T, p. (W33C) in exon 1, c.2138 DelA, p. (N713Tfs*9) in eon14, also a novel mutation at splicing acceptor site of exon 23 c.6430 - 1G>A. In factor IX, we found a novel mutation c.855G>C, p. (E285D) in exon 8. These novel mutations were not reported in any factor VIII or factor IX databases previously. The deleterious effects of these novel mutations were confirmed by PolyPhen2 and SIFT programs.

Conclusion

The protein functional and structural studies and the models built in this work would be appropriate for predicting the effects of deleterious amino acid substitutions causing these genetic disorders. These findings are useful for genetic counseling in the case of consanguineous marriages which is more common in the Saudi Arabia.

Young adults with hemophilia in the U.S.: demographics, comorbidities, and health status

Improvements in hemophilia care over the last several decades might lead to expectations of a near-normal quality of life for young adults with hemophilia. However, few published reports specifically examine health status indicators in this population. To remedy this knowledge gap, we examined the impact of hemophilia on physical and social functioning and quality of life among a national US cohort of 141 young men with hemophilia aged 18-34 years of age who received care at 10 geographically diverse, federally funded hemophilia treatment centers in 11 states between 2005 and 2013 and enrolled in the Hemophilia Utilization Group Studies. Indicators studied included educational achievement, employment status, insurance, health-related quality of life, and prevalence of the following comorbidities: pain, range of motion limitation, overweight/obesity, and viral status. The cohort was analyzed to compare those aged 18-24 to those aged 25-34 years. When compared to the general US adult population, this nationally representative cohort of young US adults with hemophilia experienced significant health and social burdens: more liver disease, joint damage, joint pain, and unemployment as well as lower high-school graduation rates. Nearly half were overweight or obese. Conversely, this cohort had higher levels of health insurance and equivalent mental health scores. While attention has typically focused on newborns, children, adolescents, and increasingly, on older persons with hemophilia, our findings suggest that a specific focus on young adults is warranted to determine the most effective interventions to improve health and functioning for this apparently vulnerable age group.

Emerging and future therapies for hemophilia

The evolution of care in hemophilia is a remarkable story. Over the last 60 years, advances in protein purification, protein chemistry, donor screening, viral inactivation, gene sequencing, gene cloning, and recombinant protein production have dramatically enhanced the treatment and lives of patients with hemophilia. Recent efforts have produced enhanced half-life (EHL) clotting factors to better support prophylaxis and decrease the frequency of infusions. Medical needs remain in the areas of alternate modes of administration to decrease the need for venous access, better treatment, and prophylaxis for patients who form antibodies to clotting factors, and ultimately a cure of the underlying genetic defect. In this brief review, the authors summarize data on EHL clotting factors, introduce agents whose mode of action is not clotting factor replacement, and list current gene therapy efforts.

Outcome after total knee arthroplasty in haemophilic patients with stiff knees

INTRODUCTION

Advanced haemophilic arthropathy of the knee is associated with progressive joint stiffness. Results after total knee arthroplasty (TKA) in stiff knees are considered to be inferior compared to those with less restricted preoperative range of motion (ROM). There is only very limited data on the results of primary TKA in haemophilic patients with stiff knees.

AIM

The purpose of this retrospective study was to evaluate the clinical outcome after TKA performed in haemophilic patients with preoperative ROM of 50° or less.

METHODS

Twenty one patients (23 knees) undergoing TKA with stiff knees were retrospectively evaluated. Mean follow-up was 8.3 years (range, 2-25). Clinical assessment included ROM, degree of flexion contracture and complication rate. Functional evaluation and pain status were assessed using the Knee Society's Scoring System (KSS).

RESULTS

Range of motion improved from 26.7° preoperatively to 73.0° postoperatively. Flexion contracture decreased from 21.7° to 8.3°. KSS increased from 22.9 to 72.9 points. Evaluation of pain revealed a decrease from 8.4 points preoperatively to 2.1 points postoperatively. All these differences were statistically significant (P < 0.005). The complication rate was 8.7% including one late periprosthetic infection, and one aseptic implant loosening. Nine patients who required VY-quadricepsplasty for knee exposure developed a mean postoperative extensor lag of 7°.

CONCLUSION

Total knee arthroplasty in haemophilic patients presenting with stiff knees results in significant improvement of function and reduction in pain. Although the clinical outcome is inferior compared to nonstiff knees reported in the literature, joint replacement surgery can be successfully performed in this particular group of patients.

Parents of children with haemophilia at an early age: assessment of perceived stress and family functioning

Haemophilia is a chronic disease that requires a multidisciplinary approach for proper management and control of its clinical manifestations. The perception and management of parents of children with haemophilia can be affected by stressful situations as a result of treatment or disease progression. The aim of this study was to evaluate the perception of stress and family functioning in parents of children with haemophilia 1-7 years. This is an observational clinical study involving 49 parents of children with haemophilia 1-7 years who attended the VIII Workshop for Parents of Children with haemophilia, organized by the Spanish Federation of Hemophilia in La Charca, Murcia (Spain). After obtaining parental consent, the questionnaires was applied to them, FACES III (family functioning) and Pediatric Inventory for Parents (perceived stress), and a record of data on the clinical characteristics and treatment. Significant differences in the perception of stressors by gender of parents were found. A family history of haemophilia, the use of port-a-cath, inhibitor development and gender of the parents were the descriptive variables most correlated with dependents variables. These variables, together with the type of haemophilia affect significantly in the parental stress and family functioning. Parents have difficulty adjusting to disease management, perceiving many stressors. Gender and family history, can hinder the proper compliance with treatments, reducing its effectiveness.

Validation of the manufacturing process used to produce long-acting recombinant factor IX Fc fusion protein

Recombinant factor IX Fc (rFIXFc) fusion protein is the first of a new class of bioengineered long-acting factors approved for the treatment and prevention of bleeding episodes in haemophilia B. The aim of this work was to describe the manufacturing process for rFIXFc, to assess product quality and to evaluate the capacity of the process to remove impurities and viruses. This manufacturing process utilized a transferable and scalable platform approach established for therapeutic antibody manufacturing and adapted for production of the rFIXFc molecule. rFIXFc was produced using a process free of human- and animal-derived raw materials and a host cell line derived from human embryonic kidney (HEK) 293H cells. The process employed multi-step purification and viral clearance processing, including use of a protein A affinity capture chromatography step, which binds to the Fc portion of the rFIXFc molecule with high affinity and specificity, and a 15 nm pore size virus removal nanofilter. Process validation studies were performed to evaluate identity, purity, activity and safety. The manufacturing process produced rFIXFc with consistent product quality and high purity. Impurity clearance validation studies demonstrated robust and reproducible removal of process-related impurities and adventitious viruses. The rFIXFc manufacturing process produces a highly pure product, free of non-human glycan structures. Validation studies demonstrate that this product is produced with consistent quality and purity. In addition, the scalability and transferability of this process are key attributes to ensure consistent and continuous supply of rFIXFc.

Management of joint bleeding in hemophilia

Hemarthrosis, the hallmark of severe hemophilia, is the major cause of serious bleeding events, disability and reduced quality of life in patients with factor VIII or factor IX deficiency. Joint bleeding is one of the greatest challenges confronting individuals treating hemophilia, and its economic impact is enormous. This article reviews the current management of hemophilic joint bleeding and discusses the potential impact of novel therapies.

Candida in saliva of Brazilian hemophilic patients

Hemophilia is a common hereditary hemorrhagic disorder, however little is known about the oral microflora of hemophilic patients. The aim of this study was to quantify the Candida and identify its species in non-stimulated saliva of hemophilic patients, and consider its relationship with clinical factors influencing Candida carriage. This study comprised evaluation of 86 hemophilic patients of the Hematology Center/UNICAMP and 43 healthy subjects as controls. All patients were submitted to anamnesis, intraoral examination and unstimulated saliva collection. Candida counts and species identification were performed in salivary samples. Candida was present in 64% of the hemophilic patients and in 44% of the healthy controls. C. albicans represented 65% and 68% of the isolated species, in hemophiliacs and control group respectively, and C. tropicalis was the second most common species in both groups. These results indicate that hemophilic patients carry Candida more frequently and in higher counts than healthy controls, independently of oral clinical parameter considered, as viral infections, complete dentures, transfusions of hemoderivatives, and salivary flow.

Past, present and future of hemophilia: a narrative review

Over the past forty years the availability of coagulation factor replacement therapy has greatly contributed to the improved care of people with hemophilia. Following the blood-borne viral infections in the late 1970s and early 1980, caused by coagulation factor concentrates manufactured using non-virally inactivated pooled plasma, the need for safer treatment became crucial to the hemophilia community. The introduction of virus inactivated plasma-derived coagulation factors and then of recombinant products has revolutionized the care of these people. These therapeutic weapons have improved their quality of life and that of their families and permitted home treatment, i.e., factor replacement therapy at regular intervals in order to prevent both bleeding and the resultant joint damage (i.e. primary prophylaxis). Accordingly, a near normal lifestyle and life-expectancy have been achieved. The main current problem in hemophilia is the onset of alloantibodies inactivating the infused coagulation factor, even though immune tolerance regimens based on long-term daily injections of large dosages of coagulation factors are able to eradicate inhibitors in approximately two-thirds of affected patients. In addition availability of products that bypass the intrinsic coagulation defects have dramatically improved the management of this complication. The major challenges of current treatment regimens, such the short half life of hemophilia therapeutics with need for frequent intravenous injections, encourage the current efforts to produce coagulation factors with more prolonged bioavailability. Finally, intensive research is devoted to gene transfer therapy, the only way to ultimately obtain cure in hemophilia.

An unusual case of pleural-based tumor with life-threatening post-operative complication

A 57-year-old male presented with hemoptysis of 4 years duration and a gradually increasing pleural mass on chest X-ray. The mass was causing pressure effects on the liver and the lungs. To rule out malignancy, thoracotomy was performed, which revealed large, thick-walled hematoma. Complete excision of mass was performed. Post-operative course was complicated by massive pleural bleeding requiring massive blood transfusions and re-exploratory thoracotomy. Subsequent tests revealed factor IX deficiency and, hence, he was managed with recombinant factor IX concentrate. This case stresses upon the fact that hereditary bleeding disorders may be diagnosed even in late adulthood with atypical presentations such as pseudotumor in pleural space. Moreover, hemophilia B may present with normal APTT levels making the diagnosis even more difficult.

Joint protection in haemophilia

Haemarthroses (intra-articular haemorrhages) are a frequent finding typically observed in patients with haemophilia. Diagnosis and treatment of these bleeding episodes must be delivered as early as possible. Additionally, treatment should ideally be administered intensively (enhanced on-demand treatment) until the resolution of symptoms. Joint aspiration plays an important role in acute and profuse haemarthroses as the presence of blood in the joint leads to chondrocyte apoptosis and chronic synovitis, which will eventually result in joint degeneration (haemophilic arthropathy). Ultrasonography (US) is an appropriate diagnostic technique to assess the evolution of acute haemarthrosis in haemophilia, although magnetic resonance imaging remains the gold standard as far as imaging techniques are concerned. Some patients experience subclinical haemarthroses, which eventually tend to result in some degree of arthropathy, especially in the ankles. Nowadays, the most effective way of protecting these patients is primary prophylaxis, which in practice changes severe haemophilia into moderate haemophilia, preventing or at least minimizing the occurrence of haemarthrosis. If primary prophylaxis is, for whatever reason not an option, secondary prophylaxis and enhanced on demand treatment should be considered. Two alternatives are available for inhibitor patients: (i) control of haemostasis using by-passing agents (rFVIIa or aPCCs) either as enhanced on demand treatment or secondary prophylaxis, as appropriate, following the same basic principles used for non-inhibitor patients and (ii) immune tolerance induction (ITI) to eradicate the inhibitor.

Transfusion-transmitted infections in haemophilia patients

One of the largest therapeutic problem during the continuous treatment of the patients with Hemophilia A and B, are viral infections as Hepatitis B and C, and HIV, and the other infective diseases, which can be transmitted by the transfusion of blood products. The aim of this study is to analyze the complications of the hemophiliacs in Kosovo which have been treated with fresh frozen plasma, cryoprecipitate and concentrated products of FVIII and FIX. We have tested 75 patients with hemophilia A or B and there were used enzyme immunoassay test-Elisa method for the following: anti-HCV, HBsAg, HIV and TPHA.The serological data showed that HCV infection was positive in 29 cases or 38,7%, whereas infection with HBV and HIV were present in a smaller percentage of the patients (2,7% HBV and 1,4% for HIV). HCV infection was present only in 9,5% of the cases of the age group under 18 years. Infected hemophiliacs with one or two infective agents were found in 34,7%, respectively 4%. Infection with T. pallidum was present at none of the examined patients with hemophilia. HCV infection was higher in severe forms of hemophilia B (44,4%), compared with severe form of hemophilia A (30%).Based on our results, despite the infrequent application of FVIII and FIX concentrates, and other anti hemophilic preparations used in treating hemophilia patients, the number of infected hemophiliacs with blood-transmittable infectious agents was substantially high, especially with hepatitis C virus.

Evaluation of bone mineral density in children with hemophilia: Mansoura University children hospital (MUCH) experience, Mansoura, Egypt

BACKGROUND

Patients with hemophilia may be at risk for developing reduced bone mineral density (BMD) for a number of reasons such as recurrent hemoarthrosis and immobilization.

AIM OF THE WORK

To assess the BMD in children with hemophilia and to correlate BMD with findings regarding the joint disease (hemophilic arthropathy).

PATIENTS AND METHODS

Thirty hemophilic patients aged 4.97 +/- 3.64 years and 30 control healthy individuals (without joint disease) aged 5.09 +/- 3.64 years were selected from the hematology unit and outpatient clinic of MUCH respectively. Anthropometric measurements were carried out in all cases. Z-score was used for weight, height, and body mass index (BMI). Joint evaluation for hemophilic patients and controls was done using Colorado PE-0.5: Half point instrument before using dual energy X-ray absorptiometry (DEXA). DEXA scanning was performed in all hemophilic patients and controls focusing on L2-L4 vertebrae.

RESULTS

There was no significant difference between hemophilic patients and controls as regard anthropometric measurements and their Z-score. There was a significant difference between hemophilic patients and controls as regard BMD and BMD Z-score (mean +/- SD) (BMD: 0.48 +/- 0.13 gm/m(2) for hemophilic patients vs. 0.55 +/- 0.14 gm/m(2) for control, p = 0.05, BMD Z-score: - 0.68 +/- 0.44 for hemophilic patients vs. 0.19 +/- 0.14 for controls p = 0.003). There was a significant difference between severe hemophilic patients (factor level assay less than 1%) and controls as regard BMD and BMD Z-score (BMD: 0.41 +/- 0.15 gm/m(2) for hemophilic patients vs. 0.55 +/- 0.14 gm/m(2) for controls, p = 0.01, BND Z-score: - 1.49 +/- 0.12 for hemophilic patients vs. 0.19 +/- 0.14 for controls p = 0.001). Also, in hemophilic patients, there was an inverse significant correlation between total joint evaluation scores and BMD Z-score (r = - 0.365, p = 0.04).

CONCLUSIONS

Children with hemophilia may have reduced BMD compared with age- and gender-matched controls. This reduction in BMD was independent of differences in age and body size. Children with more established hemophilic arthropathy exhibited the lowest BMD and BMD Z-score.

RECOMMENDATIONS

(1) Early detection of osteopenic hemophilic children using DEXA scanning, (2) bisphosphonates plus calcium for hemophilic children with reduced BMD, (3) evaluation of the effect of on demand vs. prophylaxis replacement therapy in hemophilic patients on BMD and hemophilic arthropathy.

Pathogenesis of haemophilic synovitis: experimental studies on blood-induced joint damage

Hemarthrosis is a common manifestation of haemophilia, and joint arthropathy remains a frequent complication. Even though the exact mechanisms related to blood-induced joint disease have not yet been fully elucidated, it is likely that iron deposition in the synovium induces an inflammatory response that causes not only immune system activation but also stimulates angiogenesis. This process ultimately results in cartilage and bone destruction. Investigating the processes that occur in the early stages of blood-induced joint disease in humans has been very limited. Therefore, the use of haemophilic animal models is critical to augment the understanding of this phenomenon. This article discusses three cellular regulators (p53, p21 and TRAIL) induced in synovial tissue that are important for iron metabolism. A cartilage remodelling programme induced by the release of cytokines and growth factors that result in articular damage is also discussed. Full elucidation of the pathogenesis of haemophilic joint disease is required to identify new avenues for prevention and therapy.

Coagulation disorders and inhibitors of coagulation in children from Mansoura, Egypt

Disorders of coagulation in children often prove challenging to the medical care team. The aims of this study were to assess the spectrum and prevalence of coagulation disorders among children attending Mansoura University Children Hospital (MUCH), Mansoura, Egypt. A total of 105 pediatric patients were referred to MUCH. They were divided into two groups: congenital coagulation disorders (75 cases, age 45.36 +/- 48.59 months), and acquired coagulation disorders (30 cases, age 56.13 +/- 61.61 months). All patients were subjected to thorough history taking including the nature of bleeding, family, past history, mode of inheritance, and detailed physical findings. Hemostatic tests included: platelet count, bleeding time (BT), prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT). Specific tests in the congenital group include assay of coagulation factors according to each disorder, Von Willebrand factor assay, ristocetin aggregation test, APTT mixing study for detection of inhibitors in complicated hemophilia cases, F VIII C to VWAg ratio with cut off 0.7 for detection of carriers in some hemophilia A families. Congenital disorders constituted 71.4% of the studied cases vs. 28.6% for acquired disorders. Hemophilia A (42.85%), hemophilia B (14.28%) and liver diseases (14.28%) represented the majority of the studied cases. Mild and moderate cases of hemophilia A and B are more frequent than severe cases in both types. Male sex is more frequent than female in the congenital group (94.7 vs. 5.3%, P < 0.001). Direct correlation existed between factor level assay and severity of hemophilia (r = 0.73, P = 0.006). Three mothers and one sister were identified as carrier out of four families. Anti-clotting factors inhibitor was detected in 18.2% of patients with hemophilia A and in 9.1% with hemophilia B. In conclusion, our study found that hemophilias are the most prevalent congenital coagulation disorders among children. Attention must be given for detection of hemophilia carriers and inhibitors of clotting factors.

Histological changes in murine haemophilic synovitis: a quantitative grading system to assess blood-induced synovitis

Haemophilia is a congenital disorder that results in frequent bleeding into joints, in which a chronic and debilitating arthritis develops. The presence of blood evokes an inflammatory and proliferative synovial reaction. Although the molecular mechanisms and biochemical pathways which underlie this disorder are not known, significant advances have been made by studying a murine model of human haemophilic synovitis. In order to better understand and correlate the pathological, molecular and biochemical changes, it has become necessary to grade the histological changes observed. Despite a search of the literature and review of relevant publications, none of the currently utilized schemes were appropriate, and therefore a novel grading scheme was developed. After review of over 1000 histological sections, six characteristic changes were identified: (i) synovial hyperplasia; (ii) vascularity; (iii) discolouration by haemosiderin; (iv) the presence of blood (erythrocytes); (v) villus formation; and (vi) cartilage erosion. Synovial hyperplasia and vascularity were present in variable amounts and were quantitatively scored (0-3), while the other changes were qualitatively scored as absent or present (0 or 1). Application of the grading scheme was tested and a high interobserver correlation (greater than 80%) was found. The scheme was easy to learn even by novices, with no prior experience. The availability of the histological grading scheme for murine synovitis will allow for precise evaluation of the pathological changes following joint bleeding, and facilitate correlations with molecular and biochemical changes that lead to these changes.

Von Willebrand disease within the collective of haemophilic patients as reason for unexpected bleeding episodes

In the treatment of haemophilia A and B, recombinant coagulation factors are increasingly replacing plasma-derived factor VIII and IX concentrates. Although provided with replacement therapy, individual patients may exhibit bleeding episodes, which are difficult to control. These bleeds may be caused by von Willebrand disease (VWD) as an additional underlying coagulation disorder. We report in the present study our experience that in the collective of haemophilic patients, VWD must be anticipated at least with the same order of magnitude as it appears in a normal healthy population. Among the patients at our treatment centre, two patients (1.5%) were identified as suffering from VWD in addition to haemophilia A. In the collective of haemophilia B patients at our centre, three patients (10%) with VWD were found. Two of these patients exhibited unexpected severe bleeding episodes, which could only satisfactorily be controlled by the administration of Haemate-P or DDAVP supplementary to the recombinant coagulation factor concentrate.

Haemophilia A: molecular insights

Haemophilia A is the most common inherited bleeding disorder caused by defects in the

Clin Chem Lab Med 2007;45:450–61.

Prospects for gene therapy of haemophilia

That gene therapy offers the promise of a cure for haemophilia was apparent more than a decade ago. After years of failure, substantial progress in the efficiency of gene transfer technology has recently resulted in impressive success in animal models with haemophilia. However, fears of the risks intrinsic to such therapy have been raised by the fate of two children cured of immune deficiency by gene transfer who have, however, subsequently developed leukaemia as a result of insertional mutagenesis. The purpose of this review is to outline the current status of gene therapy in light of recent successes and tragedies and to consider the prospects for curing haemophilia in the short-to-medium term.

Pathobiology of hemophilic synovitis I: overexpression of mdm2 oncogene

Hemophilia is a genetic disease caused by a deficiency of blood coagulation factor VIII or IX. Bleeding into joints is the most frequent manifestation of hemophilia. Hemarthrosis results in an inflammatory and proliferative disorder termed hemophilic synovitis (HS). In time, a debilitating, crippling arthritis, hemophilic arthropathy, develops. Although the clinical sequence of events from joint bleeding to synovitis to arthropathy is well documented, the component or components in blood and the molecular changes responsible for hemophilic synovitis are not known. Iron has long been suspected to be the culprit but direct evidence has been lacking. Previously, we showed that iron increased human synovial cell proliferation and induced c-myc expression. Here we show that bleeding into a joint in vivo and iron in vitro result in increased expression of the p53-binding protein, mdm2. Iron induced the expression of mdm2 by normal human synovial cells approximately 8-fold. In a murine model of human hemophilia A, hemarthrosis resulted in pathologic changes observed in human hemophilic synovitis and a marked increase in synovial cell proliferation. Iron, in vitro, induced the expression of mdm2. The molecular changes induced by iron in the blood may be the basis of the increase in cell proliferation and the development of hemophilic synovitis.

Induction of megakaryocytes to synthesize and store a releasable pool of human factor VIII

von Willebrand factor (VWF) is a complex plasma glycoprotein that modulates platelet adhesion at the site of a vascular injury, and it also serves as a carrier protein for factor (F)VIII. As megakaryocytes are the only hematopoietic lineage to naturally synthesize and store VWF within alpha-granules, this study was performed to determine if expression of a FVIII transgene in megakaryocytes could lead to trafficking and storage of FVIII with VWF in platelet alpha-granules. Isolex selected CD34+ cells from human G-CSF mobilized peripheral blood cells (PBC) and murine bone marrow were transduced with a retrovirus encoding the B-domain deleted form of human FVIII (BDD-FVIII). Cells were then induced with cytokines to form a population of multiple lineages including megakaryocytes. Chromogenic analysis of culture supernatant from FVIII-transduced human cells demonstrated synthesis of functional FVIII. Treatment of cells with agonists of platelet activation (ADP, epinephrine, and thrombin receptor-activating peptide) resulted in the release of VWF antigen and active FVIII into the supernatant from transduced cells. Immunofluorescence analysis of cultured human and murine megakaryocytes revealed a punctate pattern of staining for FVIII that was consistent with staining for VWF. Electron microscopy of transduced megakaryocytes using immunogold-conjugated antibodies colocalized FVIII and VWF within the alpha-granules. FVIII retained its association with VWF in human platelets isolated from the peripheral blood of NOD/SCID mice at 2-6 weeks post-transplant of transduced human PBC. These results suggest feasibility for the development of a locally inducible secretory pool of FVIII in platelets of patients with hemophilia A.