Wound healing in haemophilia--breaking the vicious cycle

Managing Relevant Clinical Conditions of Hemophilia A/B Patients

The Medical Directors of nine Italian Hemophilia Centers reviewed and discussed the key issues concerning the replacement therapy of hemophilia patients during a one-day consensus conference held in Rome one year ago. Particular attention was paid to the replacement therapy needed for surgery using continuous infusion (CI) versus bolus injection (BI) of standard and extended half-life Factor VIII (FVIII) concentrates in severe hemophilia A patients. Among the side effects, the risk of development of neutralizing antibodies (inhibitors) and thromboembolic complications was addressed. The specific needs of mild hemophilia A patients were described, as well as the usage of bypassing agents to treat patients with high-responding inhibitors. Young hemophilia A patients may take significant advantages from primary prophylaxis three times or twice weekly, even with standard half-life (SHL) rFVIII concentrates. Patients affected by severe hemophilia B probably have a less severe clinical phenotype than severe hemophilia A patients, and in about 30% of cases may undergo weekly prophylaxis with an rFIX SHL concentrate. The prevalence of missense mutations in 55% of severe hemophilia B patients allows the synthesis of a partially changed FIX molecule that can play some hemostatic role at the level of endothelial cells or the subendothelial matrix. The flow back of infused rFIX from the extravascular to the plasma compartment allows a very long half-life of about 30 h in some hemophilia B patients. Once weekly, prophylaxis can assure a superior quality of life in a large severe or moderate hemophilia B population. According to the Italian registry of surgery, hemophilia B patients undergo joint replacement by arthroplasty less frequently than hemophilia A patients. Finally, the relationships between FVIII/IX genotypes and the pharmacokinetics of clotting factor concentrates have been investigated.

Total Knee Arthroplasty among Medicare Beneficiaries with Hemophilia A and B Is Associated with Increased Complications and Higher Costs

Operations on patients with hemophilia A and B are complex. Studies evaluating postoperative outcomes and costs following total knee arthroplasty (TKA) in patients with hemophilia are limited. A retrospective review of the entire Medicare dataset from 2005 to 2014 was performed. International Classification of Disease 9th revision codes were used to identify patients with hemophilia A and B and they were matched to controls using a 1:1 random matching process based on age, gender, Charlson Comorbidity Index (CCI), and select comorbidity burden. The 90-day preoperative period was evaluated for comorbidities and the 90-day postoperative period was analyzed for outcomes and reimbursements. Logistic regression models were generated to compare outcomes between cases and controls. A total of 4,034 patients with hemophilia were identified as having undergone TKA. About 44.8% were between the ages of 65 and 74 and 62.4% were female. Although the CCI was identical in both cohorts, individual comorbidities not controlled for varied significantly. Medical complications were more frequent among the patients with hemophilia: postoperative bleeding (odds ratio [OR]: 1.7; 95% confidence interval [CI]: 1.2-2.3), deep venous thrombosis (OR: 2.3; 95% CI: 1.8-2.8), pulmonary embolism (OR: 2.9; 95% CI: 2.1-3.9), and blood transfusions (OR: 1.8; 95% CI: 1.6-1.9). Hemophilia was associated with higher odds of periprosthetic infection (1.78 vs. 0.98%, OR: 1.8 95% CI: 1.2-2.7). The 90-day reimbursements were higher for patients with hemophilia (mean: $22,249 vs. $13,017, p < 0.001). Medicare beneficiaries with a diagnosis of hemophilia experience more frequent postoperative complications and incur greater 90-day costs than matched controls following TKA. Surgeons should consider this when optimizing patients for TKA and payors should consider this for risk-adjusting payment models.

Intraosseous venous malformation of the maxilla after enucleation of a hemophilic pseudotumor: A case report

BACKGROUND

Hemophilic pseudotumor (HP) is a rare complication in patients with hemophilia. The lesion most frequently occurs in the long bones, pelvis, small bones of the hands and feet, or rarely in the maxillofacial region. Postoperative changes in HP are seldom arrested, whereas angiogenesis characterized by disturbed wound healing in HP may cause vascular malformations.

CASE SUMMARY

We report the case of an 11-year-old boy who was affected by maxillary intraosseous venous malformation. Enucleation of an HP without factor replacement was performed initially on the right side of the maxilla 3 years ago. The patient was referred to us because of painless swelling in the same location. Factor replacement and subtotal maxillectomy were performed. Pathological examinations revealed intraosseous venous malformation.

CONCLUSION

This study is the first to document the development of intraosseous venous malformation after enucleation of an HP in the maxillofacial region. Angiogenesis characterized by disturbed wound healing in patients with hemophilia may be pivotal in the pathogenesis of this condition.

Safety and dose-dependency of eptacog beta (activated) in a dose escalation study of non-bleeding congenital haemophilia A or B patients, with or without inhibitors

INTRODUCTION

Varying initial doses of activated eptacog beta (recombinant human FVIIa, rhFVIIa) may provide therapeutic options when treating bleeding in patients with congenital haemophilia who have developed inhibitory antibodies to factor VIII (FVIII) or factor IX (FIX). This study evaluated escalated doses of a new rhFVIIa product as a prelude to selecting the doses for clinical efficacy evaluation in haemophilia patients.

AIM

To assess the safety, pharmacokinetics, and laboratory pharmacodynamics of 3 doses of rhFVIIa in non-bleeding patients with congenital haemophilia A or B with or without inhibitors.

METHODS

Adult male patients (18-75 years old) with congenital haemophilia A or B (with or without inhibitors) received infusions of rhFVIIa at doses of 25, 75 or 225 μg/kg body weight. Ten patients were treated at each dose level, and each patient received 2 different dose levels. Descriptive methods were used to analyse the data.

RESULTS

Administration of rhFVIIa at all doses was well tolerated. Pharmacokinetic analyses showed that peak FVIIa plasma levels (C_max ) were approximately proportional to dose and correlated well with peak thrombin generation. Total AUC_0-inf also was approximately dose proportional. Clot formation and duration correlated with FVIIa activity. Repeat doses did not produce an immunological response.

CONCLUSION

In the first dose-escalation study of rhFVIIa to support product registration, eptacog beta at doses of 25, 75, and 225 μg/kg was pharmacodynamically active and well tolerated in non-bleeding patients with congenital haemophilia A or B.

An activated factor VII variant with enhanced tissue factor-independent activity speeds wound healing in a mouse hemophilia B model

Essentials Disorders of hemostasis can lead to delayed and defective wound healing. In hemophilia B (HB) mice, 7 days of Factor (F)IX or VIIa are needed to normalize wound healing. One dose of a highly active FVIIa variant (DVQ) restored normal wound closure time in HB mice. Coagulation factors with enhanced activity may acquire biological effects not due to hemostasis.

SUMMARY

Introduction We have previously reported that hemophilia B (HB) mice have delayed healing of cutaneous wounds and alterations in wound histology. Administration of a single dose of either factor IX or recombinant activated FVII (rFVIIa) (NovoSeven) prior to wounding did not improve wound closure time or histology. The FVIIa analog DVQ (V158D, E296V and M298Q mutations) was designed to have higher tissue factor-independent activity than rVIIa. We hypothesized that a single dose of DVQ would be more effective in restoring wound healing in HB mice. Methods Cutaneous punch wounds were made on the backs of HB and wild-type mice, and the time to wound closure was monitored. HB mice were treated with a dose of rFVIIa (10 mg kg(-1) ) or DVQ (1 mg kg(-1) ) that corrected the tail bleeding time. Skin samples were taken at various time points after wounding, fixed, and stained, and the histology was examined. Results As previously reported, wound closure times in HB mice given one dose of rFVIIa were not improved over those in untreated HB mice. Surprisingly, healing times in HB mice treated with an equally hemostatic dose of DVQ were normalized to that in wild-type mice. However, DVQ did not correct all histologic abnormalities in HB mice. Conclusions As the doses of DVQ and rFVIIa were chosen to support comparable levels of hemostasis, our data suggest that the improved healing seen with DVQ is not solely attributable to its hemostatic activity. It is possible that the improved wound healing arises through the effect of DVQ on cell signaling mechanisms.

Is it possible to use autologous adipose graft for wound repair in patients with coagulation disorders?

INTRODUCTION

Wound healing is an intricate process whereby the skin repairs itself after injury according to a specific sequence: haemostasis, inflammation, proliferation and remodelling. Cell therapy has the potential to improve wound healing conditions and can be applied in both acute and chronic wounds. Normal healing requires adequate haemostatic function. Patients with coagulation disorders whose haemostatic function is altered may not heal naturally.

AIM

The aim of this study was to show a simple, safe and inexpensive minimally invasive technique for wound repair in patients with coagulation disorders which involves the use of concentrated autologous adipose cells.

PATIENTS AND METHOD

Six patients were enrolled in this study at the Foundation of Haemophilia, in Buenos Aires, Argentina. Five patients had severe haemophilia type A and one had severe von Willebrand diseases. The average age was 37.5 years old. One patient had a retractile scar (RS) and five patients had cutaneous fistulas (CF). Suction was used to obtain autologous adipose graft from subcutaneous abdominal tissue. The graft was centrifuged and, the adipose cell concentrate was transferred to a syringe and injected in the edge of the lesion.

RESULTS

One adipose suction in each patient was performed. There were no intraoperative or postoperative complications in any of the six patients.

CONCLUSIONS

The application of autologous adipose graft is a simple and safe treatment for complicated wound repair in patients with coagulation disorders.

Heavy hematuria requiring cystectomy in a patient with hemophilia A: a case report and literature review

BACKGROUND

Hemophilia A is an X-linked recessive disorder caused by a deficiency in factor VIII. Hemophilia A affects 1 in 5,000-10,000 males. Hematuria is frequent in hemophilia. Hematuria in hemophilia is generally considered benign and manageable with conservative therapy; however, severe hematuria requiring surgical therapy has rarely been reported.

CASE PRESENTATION

A 60-year-old male with hemophilia A presented with persistent gross hematuria of unknown cause. He was treated with recombinant factor VIII products, followed by several conservative therapies as follows: clot evacuation by vesicoclysis, continuous bladder irrigation with normal saline, and intravesical instillation of aluminum hydroxide/magnesium hydroxide (Maalox); however, these failed to resolve the hemorrhaging. The patient was offered and consented to cystectomy with an ileal conduit. Intraoperative clotting was normal with the infusion of adequate recombinant factor VIII products and transfusion of fresh-frozen plasma, and the procedure was performed safely. After surgery, the patient had blood in his stool several times. No bleeding site was demonstrated in the colon by colonoscopy and (99m)Technetium-human serum albumin-diethylenetriaminepenta-acetic acid scintigraphy demonstrated that the extravasation of radioactive isotope was detected at the anal side of terminal ileum but not at the oral side. These findings were suspected to be bleeding from the ileoileal anastomosis. However, the bleeding was managed with recombinant factor VIII products.

CONCLUSIONS

Cystectomy in hemophilia may be safe, if monitored appropriately. Urinary diversion using the intestine may be avoided because anastomotic hemorrhage may become a problem.

On-demand treatment in persons with severe haemophilia

There are two main modes of replacement therapy for haemophilia patients: either to stop bleeding (on-demand) or regular infusions of clotting factor to prevent bleeds (prophylaxis). Fifty yr of clinical experience have provided evidence of the superiority of prophylaxis by showing a reduction in bleeds and development of arthropathy. Prophylaxis has been described extensively in terms of efficacy and health-economic aspects; however, on-demand treatment has received less attention. The aim of this study was to critically review the published literature on PubMed and discuss potential gaps of knowledge in on-demand treatment in persons with severe haemophilia without inhibitors by focusing on two key aspects: how on-demand treatment is provided and what outcome measures have been reported. We identified 134 papers of which 112 were excluded. Of the remaining 22 papers, 16 were comparative studies between prophylaxis and on-demand treatment and six were descriptions of on-demand treatment. The results showed limited reporting on data related to the key aspects of treatment on-demand. Early studies looked at degrees of joint bleeds and different treatment regimens in finding the optimal dose. However, from the late 1980s, there was almost no research into on-demand therapy except efficacy and safety studies of new rFVIII products and studies to prove superiority of prophylaxis over treatment on-demand. The success of on-demand therapy may depend on several factors, for example time to initial dose after a bleed and duration of treatment. Data on these key factors are limited and highlight the necessity of research to optimise replacement therapy.

Quantification of perioperative changes in von Willebrand factor and factor VIII during elective orthopaedic surgery in normal individuals

von Willebrand's disease (VWD) patients undergoing major surgery are prophylactically treated to promote haemostasis. There is variability in perioperative clinical practice; however, most guidelines suggest replacing the deficient factor to a level of 1.0 IU mL(-1) (or 100%). A review of the literature reveals a paucity of well constructed descriptive data quantifying the changes in coagulation that occur in response to surgical stress. The aim of this study was to quantify the changes in haemostatic variables occurring in response to elective orthopaedic surgery in normal individuals. Eligible subjects >18 years of age undergoing total hip or knee replacement were recruited. Blood samples were drawn at five time points: baseline, preoperatively, 30 min after surgical incision, 30 min postoperatively, postoperative day (POD) 1. Analyses included t-tests and repeated measures anova. Overall 30 patients, 21 women and 9 men, with a mean age of 65 were included in the final analysis. All von Willebrand factor (VWF) variables were seen to significantly decrease intraoperatively and increase postoperatively. VWF multimers showed a statistically significant decrease in high molecular weight multimers intraoperatively and an increase postoperatively. On subgroup analysis, age, gender and anaesthesia type were significantly correlated with changes in VWF parameters. Data presented in the current study establish a physiological baseline for VWF parameters in the normal population and demonstrate mean VWF/factor VIII levels greater than 1.0 IU mL(-1) intraoperatively. As such, current management in VWD patients does not appear to mimic the normal physiological response to surgery.

How I treat inhibitors in haemophilia

The management of patients with inhibitors is the greatest challenge facing haemophilia health professionals. Immune tolerance induction (ITI) can be successful in eliminating the inhibitor in the majority of patients, provided it is started soon after the inhibitor develops and the titre of the inhibitor is <10 BU at commencement of ITI. Acute bleeding is treated using one of two bypassing agents, which exhibit similar efficacy and safety. Surgery in inhibitor patients is challenging and should only be carried out in experienced centres.

Low intensity laser therapy speeds wound healing in hemophilia by enhancing platelet procoagulant activity

Our group has previously shown that cutaneous wound healing is delayed and histologically abnormal in a mouse model of hemophilia. Hemostasis is not only required to stop bleeding at the time of wounding, but also produces bioactive substances that promote appropriate inflammatory and proliferative responses during healing. Low intensity laser therapy (LILT) has been reported to enhance impaired wound healing in a variety of animal and human studies. The current studies were conducted to test the hypothesis that LILT can improve healing in a hemophilia B mouse model. Three daily treatments with 12 J/sq cm of 650 nm laser illumination reduced the time to closure of a 3-mm cutaneous punch biopsy wound in the hemophilic mice. All wounds were closed at 13 days in the sham-treated hemophilic mice, compared with 10 days in the LILT-treated hemophilic mice, and 9 days in wild-type mice. While LILT can speed healing by enhancing proliferation of cutaneous cells, we found that an additional mechanism likely contributes to the efficacy of LILT in the hemophilic mice. LILT enhanced the mechanical rigidity and platelet activity of clots formed from human platelet-rich plasma. Illumination of isolated platelets increased the mitochondrial membrane potential and enhanced binding of coagulation factors to the surface of activated platelets. Thus, while LILT can directly promote proliferative responses during healing, it also appears to enhance hemostasis in an animal model with impaired coagulation. These data suggest that trials of LILT as an adjunct to the usual hemostatic therapies in hemophilia are warranted.

Animal models of hemophilia

The X-linked bleeding disorder hemophilia is caused by mutations in coagulation factor VIII (hemophilia A) or factor IX (hemophilia B). Unless prophylactic treatment is provided, patients with severe disease (less than 1% clotting activity) typically experience frequent spontaneous bleeds. Current treatment is largely based on intravenous infusion of recombinant or plasma-derived coagulation factor concentrate. More effective factor products are being developed. Moreover, gene therapies for sustained correction of hemophilia are showing much promise in preclinical studies and in clinical trials. These advances in molecular medicine heavily depend on availability of well-characterized small and large animal models of hemophilia, primarily hemophilia mice and dogs. Experiments in these animals represent important early and intermediate steps of translational research aimed at development of better and safer treatments for hemophilia, such a protein and gene therapies or immune tolerance protocols. While murine models are excellent for studies of large groups of animals using genetically defined strains, canine models are important for testing scale-up and for long-term follow-up as well as for studies that require larger blood volumes.

Perioperative clotting factor replacement and infection in total knee arthroplasty

Total knee arthroplasty, or replacement (TKR), is now the most commonly performed surgical procedure performed in adults with haemophilia. It is indicated when end-stage haemophilic arthropathy results in intractable pain and reduced function. In patients with haemophilia, however, there has always been a concern about the high risk of infection, which carries with it potentially catastrophic consequences. The aims of this study were to review the case series of TKR for haemophilic arthropathy published in the medical literature, comparing the published infection rates and the differing clotting factor replacement regimes employed. Nineteen retrospective case series were identified; representing 556 TKR's in 455 patients with an overall infection rate of 7.9%. Case series which maintained a high level of clotting factor replacement throughout the first two postoperative weeks, however, had an infection rate of 2.15%, significantly lower than that of case series using the clotting factor replacement regime currently recommended in the World Federation of Hemophilia guidelines (9.22% P = 0.00545). We believe this study supports the use of a high level clotting factor replacement regime, replacing clotting factors to maintain them at a higher level for a longer period of time than currently recommended in international guidelines.

Management of muscle haematomas in patients with severe haemophilia in an evidence-poor world

Treatment studies in haemophilia focus on joint bleeds; however, some 10-25% of bleeds occur in muscles. This review addresses management of muscle haematoma in severe haemophilia, defines gaps in the published evidence, and presents a combined clinician and physiotherapist perspective of treatment modalities. The following grade 2C recommendations were synthesized: (i) Sport and activity should be based on individual factor levels, bleeding history and physical characteristics, (ii) Musculoskeletal review aids the management of children and adults, (iii) 'Time to full recovery' should be realistic and based on known timelines from the healthy population, (iv) Diagnosis should be carried out by both a clinician and physiotherapist, (v) Severe muscle bleeds should be treated similarly to surgical patients: a 50% trough for 10-14 days followed by high-level prophylaxis, (vi) Protection, rest, ice, compression and elevation should be implemented in the acute stage, and (vii) Physiotherapy and rehabilitation should be divided into: control of haemorrhage (phase 1); restoration of Range of Movement (ROM) and strength (phase 2); functional rehabilitation and return to normal living (phase 3). Recommendations specifically for inhibitor patients include: (i) Minor to moderate bleeds should be managed by home-treatment within 1 h of bleed onset using either one injection of rFVIIa 270 μg kg(-1), or two to three injections of rFVIIa 90 μg kg(-1) (2-3 h intervals), or FEIBA 50-100 U kg(-1) (repeated at 12-hourly intervals, if necessary) and (ii) Severe muscle bleeds should be supervised by the treatment centre and include bypassing agents until clinical improvement is observed.