Major surgery in a severe haemophilia A patient with high titre inhibitor: use of the thrombin generation test in the therapeutic decision

Summary. In haemophilia patients with inhibitor, elective orthopaedic surgery is usually performed under recombinant activated factor VII (rFVIIa). We report here the case of a severe haemophilia A patient with a high inhibitor who needed a bilateral total knee arthroplasty. Recombinant FVIIa was previously shown to be ineffective for the treatment of muscle and joint bleedings, and he had a history of excessive postoperative bleeding under activated prothrombin complex concentrate (APCC). Thrombin generation test (TGT) was used to assess the efficacy of Factor Eight Inhibitor Bypassing Activity (FEIBA). Insufficient correction of thrombin-generating capacity was observed after administration of 75 U kg(-1) FEIBA. In a multidisciplinary environment, a bilateral total knee arthroplasty was performed using a protocol combining immunoadsorption of inhibitors preoperatively associated with FVIII replacement during a first phase followed by FEIBA when the inhibitor reappeared. To our knowledge this is the first direct application of TGT in the management of haemophilia patients with inhibitor, which indicated that a sequential use of immunoadsorption, FVIII and FEIBA was the most appropriate treatment to perform this major elective surgery. This case demonstrates that this combined protocol can be safely used to cover major surgery in inhibitor patients. In addition, it also suggests that TGT may have a major contribution in the decision-making process of the most adapted therapy for the treatment of such high-risk patients.     

Heart transplant in a factor VIII-deficient patient with a high-titre inhibitor: perioperative management using high-dose continuous infusion factor VIII and recombinant factor VIIa.

Four years prior to transplantation, a 14-year-old boy with severe haemophilia A and a high-responding factor VIII (FVIII) inhibitor developed an anteroseptal myocardial infarct while receiving high doses of an activated prothrombin complex concentrate (PCC). Cardiac transplantation was required for survival because of the ensuing cardiomyopathy. At surgery, the patient's inhibitor titre was 1.8 Bethesda units (BU). High-dose bolus therapy, followed by a continuous infusion of FVIII provided excellent operative and initial postoperative haemostasis without additional blood-product support. Once anamnaesis developed on day 6 postoperatively, recombinant factor VIIa (rFVIIa) therapy was initiated. Haemostasis remained excellent, except for the transient increase in chest-tube bleeding that was noted on day 7. epsilon-Aminocaproic acid was added and haemostasis was re-established. On day 15, rFVIIa was replaced with alternate day infusions of prothrombin complex concentrates (PCCs). On day 21 following the transplant, the patient was discharged, remaining on daily FVIII immune tolerance and thrice-weekly PCC prophylaxis. He remains well 24 months after transplant with an inhibitor titre of 39 BU. This paper describes the second case of cardiac transplantation complicated by haemophilia and an inhibitor, and discusses preoperative planning and operative and postsurgical haemostasis management.     

Intestinal surgery with activated recombinant factor VII prophylaxis in patients with haemophilia A and high responding inhibitors: a report of five cases.

Five patients with severe haemophilia A and high responding inhibitors underwent laparoscopic or open surgery on the digestive tract (appendicectomy, cholecystectomy, partial colectomy, or haemorrhoidectomy) with recombinant activated factor VII (rFVIIa) prophylaxis. rFVIIa was administered at a dose of 92-127 mug/kg prior to surgery and then every 2 h for 18-56 h before increasing the dosing interval. One patient was switched to a continuous infusion after 48 h of rFVIIa boluses. rFVIIa treatment lasted between 5 and 14 days in four patients, with good or excellent efficacy (total dose, 3.13-9.28 mg/kg). The fifth patient, who underwent surgery for prolapsed haemorrhoids, bled on day 6 and day 10 after the procedure, despite a satisfactory prothrombin time and factor VII coagulant level. The rFVIIa dose regimen was increased after the second bleeding episode, then the bleeding rapidly ceased after this modification to the treatment regimen. The total dose of rFVIIa used was 12.65 mg/kg, and treatment lasted 17 days. Antifibrinolytic treatment was used concomitantly in all five patients. Clinical and biological tolerability was excellent, and no increase in the anti-factor VIII inhibitor titre was observed. These results suggest that rFVIIa prophylaxis is effective in haemophilia A patients with factor VIII inhibitors who are undergoing elective or emergency intestinal surgery. Further studies are required to optimize the dose regimen and treatment period according to the surgical indication and technique.     

Seventy‐two total knee arthroplasties performed in patients with haemophilia using continuous infusion

Background and Objectives Total knee replacement (TKR) is the treatment of choice in case of end‐stage knee arthropathy, the main complication of haemophilia. We report here a retrospective evaluation of 72 total knee replacement in 51 haemophilia A and B patients using continuous infusion of factor concentrates (CIFC). Materials and Methods Patients were evaluated on the basis of the following efficacy and safety criteria: range of motion, surgery‐related blood loss by three different methods, factor consumption and occurrence of short and long term complications. Results Kaplan–Meier analysis showed a removal‐free survival of TKRs of 88.4% 10 years after surgery. Most patients were satisfied with their prosthesis and described pain relief and improved mobility and better quality of life after surgery. The long term follow‐up showed a mean range of motion at 86° with a flexion deformity of 4°. The blood loss differed significantly according to the method used for measurement. No life‐threatening bleeding occurred. Twenty six haematomas (36.1%) and 2 haemarthroses (2.7%) occurred in 38.8% of cases during the first three postoperative weeks, with no significant impact on the orthopaedic outcome. The average factor consumption during hospitalization was 79 IU/kg/day for patients with haemophilia A and 99 IU/kg/day for patients with haemophilia B. Infections occurred in 4.1% of patients. One patient with severe haemophilia A developed an inhibitor. Conclusions The multidisciplinary approach and the homogeneous management of our large cohort allowed the achievement of excellent functional results. Our results confirmed previously reported data on the safety and efficacy of CIFC in situations requiring intensive factor replacement, such as TKR surgery.     

Knee and hip arthroplasty infection rates in persons with haemophilia: a 27 year single center experience during the HIV epidemic

Total joint replacement (TJR) is an option for the management of chronic haemophilic arthropathy. Because surgery is technically challenging, there is a high rate of deep prosthetic infections, particularly in human immunodeficiency virus (HIV)-infected individuals. We determined the incidence of deep infection rates following total knee and hip arthroplasties in HIV-seropositive and HIV-seronegative persons with haemophilia. Fifty-one primary joint replacements were performed on 32 patients seen at a regional comprehensive haemophilia care center from 1975 to 2002. Thirty prostheses were placed in patients who were HIV-seropositive prior to surgery (n = 14) or seroconverted later (n = 16). Median age at the time of surgery was 33 years (range: 20-61) among 19 HIV-seropositive patients and 35 years (range: 26-74) among 13 HIV-negative patients. Median duration of follow-up was 83 months (range: 2-323). Rate of primary joint infection per artificial joint-year by HIV status was compared by Poisson regression. Main outcome measures were the incidence of primary replacement joint infections by HIV status. Deep infections developed in five (9.8%) of 51 replacement joints. There were two infections during 204.15 joint-years without HIV infection and three infections during 205.28 joint-years with HIV infection. The incidence rate of joint infection (0.98 vs. 1.46 per 100 joint-years) was not increased with HIV (relative risk, RR: 1.49, 95% CI: 0.25-8.93, P = 0.66). We conclude that HIV infection is not a contraindication to knee or hip replacement arthroplasty in the appropriate clinical setting.     

Prophylaxis with FEIBA in paediatric patients with haemophilia A and inhibitors

The benefits shown with factor VIII (FVIII) prophylaxis relating to joint health and quality of life (QoL) provide the rationale for FEIBA prophylaxis in haemophilia A patients with persistent FVIII inhibitors. FEIBA has previously shown efficacy in preventing bleeds in inhibitor patients who failed to respond to, or were ineligible for immune tolerance induction (ITI). The study examined the outcome of paediatric patients undergoing long‐term FEIBA prophylaxis. A retrospective chart review included severe haemophilia A patients with persistent inhibitors aged ≤13 years at the start of FEIBA prophylaxis. Baseline characteristics captured dose, frequency of prophylaxis, history of inhibitor development, including baseline titre, historical peak titre and history of ITI. Outcome measurements included annual bleed rate before and during FEIBA prophylaxis, joint status and school days missed. Sixteen cases of FEIBA prophylaxis from two centres are presented. The mean age of subjects at prophylaxis initiation was 7.5 ± 3.6 years and median baseline inhibitor titre was 23 (range 3.1–170) BU. Prior to prophylaxis initiation, median annual joint bleeds among all patients was 4 (0–48), which dropped significantly after the first year of prophylaxis, to a median annual joint bleed rate of 1 (0–7; P = 0.0179). Subsequent years (median = 9) of prophylaxis therapy demonstrated similarly low annual joint bleed rates. There were no life‐threatening bleeds, no viral seroconversions or thrombotic events during FEIBA prophylaxis treatment. FEIBA prophylaxis was effective for preventing joint bleeds and subsequent joint damage, delaying arthropathy and improving outcomes in children with haemophilia A and inhibitors to FVIII, who failed or were ineligible for ITI.     

Rituximab for adolescents with haemophilia and high titre inhibitors

Neutralizing alloantibodies (inhibitors) to factor VIII or factor IX develop in approximately 25% of patients with haemophilia A and <3% of patients with haemophilia B treated with factor concentrate. Patients with high titre inhibitors, in whom immune tolerance therapy fails, have few treatment options. Targeted anti-B-cell therapy with rituximab (chimeric anti-CD20) has been useful in several antibody-mediated autoimmune states. Case reports of rituximab treatment in small numbers of haemophilia patients with inhibitors have been inconclusive. We describe three adolescent patients with severe haemophilia and inhibitors treated with four weekly doses of rituximab, 375 mg m(-2). Treatment with rituximab was effective in reducing the inhibitor titre in two of three patients. Rituximab may be beneficial for patients with severe haemophilia and inhibitors in whom standard therapies have failed, but larger prospective studies are required to determine safety, efficacy and predictors of success.     

Inhibitor incidence after intensive FVIII replacement for surgery in mild and moderate haemophilia A: a prospective national study in the Netherlands

Inhibitor development is currently the most severe complication in mild/moderate haemophilia A patients, causing increased bleeding tendency, hospitalization and mortality. It has been suggested that receiving high doses of factor VIII (FVIII) concentrates for surgical procedures is an important risk factor for inhibitor development in these patients. The current multicentre study aimed to determine prospectively the incidence of inhibitor development after intensive FVIII replacement therapy for surgical procedures in patients with mild/moderate haemophilia A. All consecutive patients with mild/moderate haemophilia A were included when they required at least 10 000 iu of FVIII concentrates (or 250 iu/kg) for 5 or more days for a surgical procedure. Potential clinical risk factors for inhibitor development and results of inhibitor tests were collected. Forty-six patients with a median age of 54 years (interquartile range, 40-59 years) were included in the study. F8 genotyping revealed 20 different missense mutations. Patients received either recombinant (65%) or plasma-derived FVIII concentrates (35%) by intermittent bolus injections (41%) or continuous infusion (57%). Two patients developed a low titre inhibitor post-operatively. The incidence of inhibitor development following intensive treatment for surgery in this unselected prospective cohort of mild/moderate haemophilia A patients was 4% (95% confidence interval, 0·5-14·8).     

How we treat: considerations for physiotherapy in the patient with haemophilia and inhibitors undergoing elective orthopaedic surgery

Ten weeks prior to a scheduled left total knee arthroplasty, a 25‐year‐old man with severe haemophilia A and a high‐titre inhibitor presented to the physical therapist for a preoperative assessment at the haemophilia treatment centre (HTC). Prior to the recommendation to proceed to surgery, the therapist and other members of the multidisciplinary care team had surmised that, despite two previous radiosynovectomies, an arthroscopic synovectomy, and most recently at the age of 18 years, an arthroscopic debridement, the patient continued to have a progression of joint disease manifested by pain, restricted range of motion and reduced strength. Based on these findings and the patient’s history of consistent adherence to and follow‐through with recommended treatments, the HTC staff and orthopaedic surgeon determined that he was a good candidate for total knee replacement. The patient’s pain and joint disease severely limited his mobility and participation in functional activities. The most recent radiographs were notable for severe tricompartmental arthropathy of the left knee with joint deformity, flexion contracture, and osteoporosis. When queried about current haemostatic therapy during the initial preoperative visit with the physical therapist, the patient explained that he was self‐infusing a bypassing agent to treat active bleeds and as prophylactic treatment before participating in vigorous physical activity, as advised by his haematologist. He had previously managed his joint pain with cyclooxygenase‐2 inhibitors and both short‐ and long‐acting opioids, in addition to physical therapy. His current personal inventory of mobility and rehabilitative aids consisted of crutches, compressive wraps, and a cold‐compression unit. Further assessment of relevant environmental and psychosocial factors revealed that the patient was living with his girlfriend and 3‐year‐old daughter, for whom he was the primary caregiver, in a two‐story home with five steps to enter. He was also working part‐time from home as a computer consultant. The visit concluded with a formal physical assessment and discussion of next steps, including plans for additional preoperative physical therapy sessions. The therapist also informed the patient about what to expect postoperatively in terms of rehabilitation and recovery.     

Rituximab for congenital haemophiliacs with inhibitors: a Canadian experience

When a high titre inhibitor develops in a patient with haemophilia, attempts are made to eradicate it through immune tolerance induction therapy (ITI) involving the frequent and regular administration of factor, usually for months to years. ITI is successful in only two thirds of patients prompting investigators to explore alternate regimens to use in haemophiliacs failing conventional ITI. Rituximab is an anti-CD20 monoclonal antibody, which has shown promise in the treatment of B-cell-mediated disorders. We developed a protocol for the use of rituximab in haemophilia A (HA) patients failing conventional ITI or in those haemophiliacs where the likelihood of success of conventional ITI is poor. Patients receive 375 mg m(-2) of intravenous rituximab weekly for 4 weeks followed by monthly (up to 5 months) until inhibitor disappearance and establishment of normal FVIII pharmacokinetics (recovery and half-life). Patients are concurrently placed on recombinant FVIII (100 U kg(-1) day(-1)). We have placed five haemophiliacs (four children with severe HA, and one adult with mild HA) on this protocol. In three patients (two with severe HA and one with mild HA) inhibitors disappeared although in neither severe haemophiliac did FVIII pharmacokinetics completely normalize. The fourth patient had a significant drop in inhibitor titres although not a complete disappearance of the inhibitor. All four of these patients ceased bleeding following rituximab. The fifth patient had no response to rituximab. This non-responding patient was not placed on concurrent FVIII. Our five cases suggest that rituximab may hold promise in the eradication of inhibitors. Prospective randomized studies are required to determine the value of this agent in inhibitor management.     

Immune tolerance induction with a high purity von Willebrand factor/VIII complex concentrate in haemophilia A patients with inhibitors at high risk of a poor response

Immune tolerance induction (ITI) is effective in approximately 70% of haemophilia patients with inhibitors. Poor prognostic factors are age >6 years, ITI started >1 year from inhibitor development, inhibitor peaks >200 BU, inhibitor titre >10 BU when ITI is started and previously failed ITI. The objective of this study was to identify the effectiveness in ITI of a high purity von Willebrand factor/factor VIII (VWF/FVIII) complex concentrate in inhibitor patients at high risk of failure. Patients with severe or moderate haemophilia A and high responding inhibitors who had at least one poor prognostic factor for ITI failure were prospectively followed-up. Success was defined by undetectable inhibitor, recovery and half life >66% of expected values. ITI dose regimens were chosen by each haemophilia centre. Seventeen haemophiliacs (16 severe, one moderate), aged 4-54 years (median 23) were followed-up for 6-71 months. Poor prognostic factors were delayed-onset ITI (n = 16), age >6 years (n = 16), previously failed ITI (n = 4), inhibitor peak >200 BU (n = 2) and inhibitor >10 BU when ITI was started (n = 4). Complete success was obtained in nine patients (53%) after 4-30 months of treatment (median 24), including two of four patients who had previously failed ITI. Seven patients achieved a partial success, with sustained low inhibitor titres (median 1.5 BU, range 1.1-2.8) but abnormal recovery and/or half-life, while the remaining patient withdrew ITI after 12 months when the inhibitor titer was still 70 BU. These findings suggest that high purity VWF/FVIII complex concentrates are effective in ITI, even in patients at high risk of failure.     

Postauthorization safety surveillance of ADVATE [antihaemophilic factor (recombinant), plasma/albumin‐free method] demonstrates efficacy,safety and low‐risk for immunogenicity in routine clinical practice

Summary. Postauthorization safety surveillance of factor VIII (FVIII) concentrates is essential for assessing rare adverse event incidence. We determined safety and efficacy of ADVATE [antihaemophilic factor (recombinant), plasma/albumin‐free method, (rAHF‐PFM)] during routine clinical practice. Subjects with differing haemophilia A severities and medical histories were monitored during 12 months of prophylactic and/or on‐demand therapy. Among 408 evaluable subjects, 386 (95%) received excellent/good efficacy ratings for all on‐demand assessments; the corresponding number for subjects with previous FVIII inhibitors was 36/41 (88%). Among 276 evaluable subjects receiving prophylaxis continuously in the study, 255 (92%) had excellent/good ratings for all prophylactic assessments; the corresponding number for subjects with previous FVIII inhibitors was 41/46 (89%). Efficacy of surgical prophylaxis was excellent/good in 16/16 evaluable procedures. Among previously treated patients (PTPs) with >50 exposure days (EDs) and FVIII ≤2%, three (0.75%) developed low‐titre inhibitors. Two of these subjects had a positive inhibitor history; thus, the incidence of de novo inhibitor formation in PTPs with FVIII ≤2% and no inhibitor history was 1/348 (0.29%; 95% CI, 0.01–1.59%). A PTP with moderate haemophilia developed a low‐titre inhibitor. High‐titre inhibitors were reported in a PTP with mild disease (following surgery), a previously untreated patient (PUP) with moderate disease (following surgery) and a PUP with severe disease. The favourable benefit/risk profile of rAHF‐PFM previously documented in prospective clinical trials has been extended to include a broader range of haemophilia patients, many of whom would have been ineligible for registration studies.     

A prospective clinical trial of implantable central venous access in children with haemophilia

To assess the risks associated with the use of central venous ports in children with haemophilia, 15 HIV-negative patients were prospectively evaluated. Port insertion was required for immune tolerance in two inhibitor patients and continuous prophylaxis in 13 patients with severe factor VIII deficiency, for whom surgery was covered with recombinant factor VIII (rFVIII), then given daily at home until day 6. One inhibitor patient (titre 7 BU/ml) received high-dose rFVIII by continuous infusion until day 3, followed by an immune tolerance treatment scheme; the other (titre 12 BU/ml) was given recombinant activated factor VII by continuous infusion until day 7. After training on the use of the port, all patients continued their infusion programme at home. All ports remained in place for a median period of 413 d (range 125–509). The median number of entries into the port was 184 (range 53–567). Port-site haematoma and infection occurred in one patient on day 7 when an inhibitor became detectable (titre 12 BU/ml). An infectious complication occurred in another patient after 310 d. The port infection rate was 0.42 per 1000 patient-days (0.33 per 1000 entries into the port). This protocol for port placement with short hospitalization appears feasible and safe.     

Safety and efficacy of KOGENATE® Bayer in previously untreated patients (PUPs) and minimally treated patients (MTPs)

Summary.  Safety and efficacy of KOGENATE^® Bayer (Kogenate^® FS), a second-generation full-length recombinant factor VIII formulated with sucrose as stabilizer and produced without the addition of human albumin during purification and the final formulation, was assessed in a prospective, international clinical trial including 31 previously untreated patients (PUPs) and minimally treated patients (MTPs) with severe haemophilia A in home therapy and surgery. Factor VIII inhibitor development was monitored and mutation type profiles were analysed. As of 30 June 2000, the patients received a total of 2.729 infusions (mean 88; range 6–274) for bleeding episodes, surgery or prophylactic treatment. No unexpected drug-related adverse events were observed. Four patients developed an inhibitor after 3–12 exposure days (EDs). One patient successfully underwent immune tolerance treatment; inhibitors in two patients disappeared spontaneously with on-demand treatment, while the inhibitor titre remains low in one patient. Twenty-nine patients (93%) with more than 20 EDs can be regarded as at low risk for inhibitor development. In conclusion, KOGENATE^® Bayer is efficacious and well-tolerated for treatment of children with severe haemophilia A. The incidence of inhibitor formation is not different to that observed with other recombinant or plasma-derived products.     

Surreptitious bleeding in surgery: a major challenge in coagulation

Apart from inadequate surgical haemostasis, postoperative bleeding can be related to acquired disorders of platelet number, platelet function or coagulation proteins (e.g. Vitamin K deficiency, DIC or liver injury). We highlight our experience with three patients who suffered life-threatening bleeding in the postoperative setting. The three patients - a 47-year-old man and 70- and 74-year-old women -- all had negative histories for excessive bleeding with prior surgeries, and all had normal preoperative PT and aPTT tests. Surgeries were resection of ischaemic bowel, cholecystectomy and coronary artery bypass grafting. All patients experienced unexpected bleeding within the first few postoperative days requiring multiple red cell transfusions and surgical re-explorations. Evaluations within the first 4--7 days after surgery revealed that these three patients had developed prolonged aPTT due to demonstrable factor VIII antibodies initially at low titre. One patient was treated with high doses human factor VIII, corticosteroids, intravenous gammaglobulin and plasma exchanges. The inhibitor was no longer demonstrable after 6 weeks of such therapy, and he has remained in remission without therapy. The second patient was initially treated with high-dose human factor VIII infusions. Five months later, prednisone and 6-mercaptopurine were begun for worsening inhibitor titre and diffuse purpura and subcutaneous haematomas. The factor inhibitor remitted, but the patient died from liver failure related to post-transfusion hepatitis. The third patient was initially managed with high-dose human factor VIII. Two months later, worsening inhibitor titre and tongue haematoma was treated with activated prothrombin complex, corticosteroids and cyclophosphamide. Eight years later, she is on no therapy, demonstrates a mild bleeding tendency and has a stable low-titre inhibitor. There have been a few case reports of inhibitors to coagulation factors including factor VIII becoming manifest in the postoperative setting but surgery has not been widely recognized as an underlying cause for acquired haemophilia. This paper speculates on pathogenesis and reviews treatment options. This syndrome is remarkable for its abrupt onset in the first few postoperative days and for its substantial morbidity. The problem is potentially reversible with immunosuppressive therapy. Clinicians should be aware of this syndrome, considering acquired haemophilia in patients with unexpected postoperative bleeding.     

Treatment of acquired haemophilia with factor eight inhibitor bypassing activity

Haemorrhagic manifestations in patients with acquired haemophilia can be fatal if not recognized and treated appropriately. A retrospective analysis of the efficacy of factor eight inhibitor bypassing activity (FEIBA) in patients with acquired haemophilia treated in three medical centres in the past 10 years was conducted. The median inhibitor titre at treatment was 128 Bethesda Units (BU) in patients with severe and 34 BU in patients with moderate bleeding; P = 0.001. The majority of patients received FEIBA at a dose of 75 u kg-1 every 8-12 h. The number of FEIBA doses administered was higher in patients with severe compared with moderate haemorrhage, 10 vs. 6 doses per bleeding episode; P = 0.001. Complete response (CR) was achieved in 76% of severe and 100% of moderate bleeding episodes with a total CR of 86%. When compared with patients with human inhibitor titre <50 BU, those with titre >51 BU at treatment had lower median porcine titre, 1 vs. 9.5 BU; P < 0.05, fewer doses of FEIBA, 6 vs. 8.5 doses; P < 0.05, and shorter time to CR, 29 vs. 42 h; P < 0.05. Patients exposed to factor VIII concentrates prior to FEIBA had significantly higher maximum recorded human inhibitor titre compared with patients without such exposure, 273 vs. 38 BU; P = 0.0001. Treatment with FEIBA was very well tolerated and with very few side effects. This study provides evidence that FEIBA is an effective agent in acquired haemophilia and suitable for all types of patients regardless of severity of haemorrhage, underlying disease or inhibitor titre.     

Acquired haemophilia A in women postpartum: management of bleeding episodes and natural history of the factor VIII inhibitor

Abstract: The present study reports on the treatment of bleeding episodes and the natural history of factor VIII inhibitors in 4 patients with acquired haemophilia A postpartum. Low titre type II factor VIII inhibitors in 3 patients and high titre type I inhibitor in 1 patient became apparent immediately to 7 months after delivery. High dose human factor VIII concentrate substitution was effective in controlling bleeding episodes in two cases of factor VIII inhibitor type II, but ineffective in 1 patient with high titre type I factor VIII inhibitor. High dose gammaglobulin intravenously in 1 patient with type II factor VIII inhibitor induced a partial correction of factor VIIIc levels for 2 wk. Immunosuppressive treatment in all 4 patients with acquired haemophilia A postpartum did not reduce the potency of the factor VIII inhibitors. The low titre type II inhibitors spontaneously disappeared in all 3 patients within a few months to 1 yr after discontinuation of the immunosuppressive treatment. The high titre type I factor VIII inhibitor persisted for more than 24 yr. We conclude that immunosuppression in 4 women with acquired haemophilia A postpartum did not significantly affect the factor VIII inhibitor titre.     

Prophylactic recombinant factor VIIa in haemophilia patients with inhibitors

Prevention of bleeding, especially into joints, with prophylactic factor infusions is the most effective treatment for severe haemophilia patients. Approximately 15-30% of patients with factor VIII deficiency and 3-5% of patients with factor IX deficiency develop neutralizing antibodies (inhibitors) to factor precluding their use. Such patients often have significant bleeding complications including life- and limb-threatening bleeds and severe joint disease. Prophylaxis for such patients is not generally considered because of the fact that the standard (bypassing) agents for such patients are not as effective as natural factor replacement, because of concerns for thrombotic complications and also because of the very high cost of bypassing agents. We treated two patients with high titre inhibitors with prophylactic recombinant factor VIIa (rFVIIa). The first patient was treated as a result of development of a target joint and to reduce the use of agents that can lead to anamnesis of his inhibitor. The second patient had multiple severe bleeds and was hospitalized 20% of the time over a 2-year period. He had a very poor quality of life. Both patients had shown good responses previously to rFVIIa for treatment of bleeds. Both patients had an outstanding response to prophylaxis albeit at a very high cost. Prophylaxis with rFVIIa can be an effective approach in select inhibitor patients with severe complications related to bleeding.     

Factor VIIa in the treatment of haemophilia

Recombinant FVIIa is being developed for treatment of haemophiliacs with antibodies against FVIII/FIX. rFVIIa was shown to be haemostatically active in haemophilia A and B dogs as well as in 20 haemophilia patients (one haemophilia B and 19 haemophilia A patients). Thirteen patients were treated for life-threatening bleedings and nine at surgery (dose: 60-90 micrograms/kg q 3-4 h). One patient underwent synovectomy in a knee joint under the cover of rFVIIa as the sole coagulation factor without any problems. One patient with FXI deficiency was successfully treated at an orchidectomy. The haemophilia B patient was treated in association with a compartment syndrome (surgical fasciotomy) with a complete haemostasis. He later uneventfully underwent skin grafting. Two CNS bleeds, a severe mouth bleed were treated as well as an extensive nasopharyngeal bleed in a patient with an acquired inhibitor against FVIII. Shortening of the prothrombin time as well as of the APTT was seen. No side-effects were observed. It is speculated whether FVIIa in complex with not only tissue factor but also phospholipids exposed at the site of injured cells directly activates FXa and thereby the final common pathway of the coagulation cascade.     

High-titre factor VIII inhibitor in two children with mild haemophilia A

A frequently encountered complication of therapy given to patients with severe haemophilia A is the development of antibodies to infused factor VIII. While much less common, inhibitors also occur in patients with mild or moderate severity haemophilia A. Often thought to be of low titre and transient, several cases of high-titre inhibitors have been described in patients with mild or moderate haemophilia A. Generally these occur in adults or adolescents following significant infused factor VIII exposure. A review of reported cases revealed only two cases of high-titre inhibitor formation in mild haemophilia A patients younger than 10 years of age. We wish to report our experience with an additional two children with mild haemophilia A and high titre inhibitors, and offer suggestions for the management of these children.