Laboratory, clinical and therapeutic aspects of acquired hemophilia A

Bleeding After Central Venous Catheter Placement in a Patient With Undiagnosed Acquired Hemophilia A: A Case Report

Acquired hemophilia A is a rare condition caused by autoantibodies against endogenous coagulation factor VIII, which results in spontaneous bleeding. Workup of a patient with difficult hemostasis after removing and placing a central venous catheter led to the diagnosis of acquired hemophilia A. A 64-year-old man was transferred with an intramuscular right thigh mass. Initial biopsy at an outside facility showed degenerated muscle and coagula and he was transferred for incisional biopsy and definitive treatment. The patient had difficult venous access, and a right internal jugular venous catheter was placed. The catheter insertion site showed slow continuous bleeding. Achieving adequate hemostasis after removing the catheter was difficult, and a hematoma formed after the placement of an infraclavicular axillary venous catheter under ultrasound guidance. Coagulation studies revealed a prolonged activated partial thromboplastin time at 96 seconds. The patient was then diagnosed with acquired hemophilia A by enzyme-linked immunosorbent assay using anti-factor VIII antibodies. Even if ultrasound-guided central venous catheterization is performed carefully, bleeding may occur in some patients, suggesting the possibility of coagulopathy. Decision-making for performing central venous catheterization requires extensive knowledge of coagulopathies to understand the causes of bleeding complications.

Acquired Haemophilia A: An Intriguing Disease

Abstract. Acquired Haemophilia A is a rare acquired bleeding disorder caused by Factor VIII autoantibodies, which neutralise FVIII activity. These inhibitors differ from alloantibodies against FVIII, which can occur in congenital Haemophilia A after repeated exposures to plasma-derived or recombinant FVIII products. In most cases, the disease occurs suddenly in subjects without a personal or familiar history of bleedings, with symptoms that may be mild, moderate, or severe. However, only laboratory alterations are present in ~ 30% of patients. The incidence varies from 1 to 4 cases per million/year; more than 80% of patients are elderly, males and females are similarly affected. There is a small peak of incidence related to pregnancy in young women aged 20–40 years. The disease may be underdiagnosed in the elderly. The diagnostic algorithm is based on an isolated prolonged activated partial thromboplastin time, normal thrombin time, absence of Lupus Anticoagulant, and a mixing test that reveals the presence of an inhibitor: the finding of reduced FVIII activity and the detection of neutralising autoantibodies against FVIII lead to the diagnosis. The disease is idiopathic in 44%–63% of cases, while in the others etiological factors are present. Bleeding prevention and treatment are based on therapeutic tools as by-passing agents, recombinant porcine FVIII concentrate or, in a limited number of cases, FVIII concentrates and desmopressin. As soon as the diagnosis has been made, immunosuppressive therapy must be started to eradicate the inhibitor. Better knowledge of the disease, optimal management of bleeding and eradication of the inhibitor have significantly reduced morbidity and mortality in most patients.

The factor VIII:C/VWF:Ag ratio as a useful tool to predict relapse in patients with acquired haemophilia A: A retrospective cohort study

INTRODUCTION

Acquired haemophilia A (AHA) is a rare autoimmune bleeding disorder caused by the presence of autoantibodies against coagulation factor VIII (FVIII). The mortality rate remains high. International recommendations define complete remission as undetectable inhibitor (<0.6 Bethesda Units [BU]) and normal FVIII activity (FVIII:C) that persists after immunosuppressive therapy stopped. For patients achieving remission, the risk of relapse reaches 20%. The risk factors for this relapse are not well known.

AIM

In this study, we examined the accuracy of the FVIII/W ratio (FVIII:C/von Willebrand Factor Antigen (VWF:Ag) ratio) to predict relapse in 64 consecutive patients with AHA.

RESULTS

In this cohort, all patients had a very low FVIII/W ratio at the time of diagnosis, and this value progressively increased in the first weeks of immunosuppressive treatment. In our study, 9/55 (14%) did not achieve complete remission. Twenty-seven patients were followed long enough (more than a year) to show that in the 22 patients who did not relapse, the FVIII/W ratio remained durably normalized. By contrast, in the five patients who relapsed during follow-up, we noted either no normalization of the FVIII/W ratio, or a secondary decrease to an abnormal value of <0.7 after initial normalization. In all patients who relapsed, the ratio was the first abnormal biological result to be observed, always preceding changes in the activated partial thromboplastin time (aPTT), FVIII:C and anti-FVIII reappearance.

CONCLUSION

These data suggest that the FVIII/W ratio could be considered a sensitive biological marker to predict recovery and/or relapse in AHA.

A Case of Acquired Haemophilia A in a Patient with Chronic Myelomonocytic Leukaemia

A 67-year-old male, with a known diagnosis of myelodysplastic syndromes with multilineage dysplasia (MDS-MLD) was admitted to our hospital with a primary complaint of subcutaneous bleeding in his left thigh. Laboratory data showed anaemia and prolongation of activated partial thromboplastin time (85.8 s, normal range 24-39 s) without thrombocytopenia. Coagulation factor VIII (FVIII) activity was less than 1% (normal range 60-150%), and a FVIII inhibitor was identified and quantified at 166 BU/mL to indicate a diagnosis of acquired haemophilia A (AHA). A recent, but sustained circulating monocytosis (>1 × 10⁹/L) was observed, which combined with elevated numbers of neutrophil and monocytic cells in the marrow, suggested evolution of MDS-MLD to chronic myelomonocytic leukaemia (CMML), coinciding with AHA. Further analysis revealed a karyotype of 46, XY, i(14) (q10), which was the same abnormality previously identified in the patient. To treat bleeding caused by AHA, steroid and activated prothrombin complex concentrate were administered. Azacitidine (AZA) was used to treat CMML. During the clinical course, bleeding partially improved; however, subsequent acute myocardial infarction occurred on day 87. Worsening bone marrow failure was observed 4 months after the original admission, despite administration of AZA therapy, and the patient died due to bleeding from AHA. This case suggests that the evolution of MDS to CMML status can be associated with AHA conferring a bleeding tendency.

Acquired Hemophilia A: Experience of a Tertiary Care Institute from North India

Acquired hemophilia A (AHA) is an uncommon bleeding disorder infrequently reported among Indians. The present retrospective data comprises eight cases of AHA over a period of 15 years. The mean age of patients was 59.7 years. The activated partial thromboplastin time was prolonged in all cases and the inhibitor screen showed the presence of inhibitors. Factor VIII: C assay was performed in 7 cases and all cases demonstrated low levels. Lupus anticoagulant was negative. Six patients were managed with steroids and symptomatic supportive care. These patients were followed up for a mean period of 3.5 years (range 1-5 years). Of these, there was one fatality prior to initiation of therapy and one patient continues to have inhibitors.

Acquired hemophilia with thrombosis in a cancer patient: an unusual presentation

: Acquired hemophilia A (AHA) which presents with spontaneous severe intramuscular, mucosal and/or subcutaneous bleeding is a rare bleeding disorder. Even 50% of AHA patients are defined as idiopathic; 10% of cases are related with malignancy. Here, we present a case of AHA in a 43-year-old lady who was diagnosed with malignancy and venous thromboembolism on vena cava 2 years ago. To the best of our knowledge, this is the first report in literature presented with both acquired hemophilia and thrombosis associated with malignancy. A routine workup for malignancy like solid tumors, lymphoproliferative, or myeloproliferative diseases should be performed and followed up for a long time despite clinical improvement for individuals presented with AHA. Moreover, because of warfarin treatment, the diagnosis may be difficult and delayed. Clinicans should rule out AHA in patients who are on warfarin treatment and have abnormal coagulation tests.

Identification of people with acquired hemophilia in a large electronic health record database

Background

Electronic health records (EHRs) can provide insights into diagnoses, treatment patterns, and clinical outcomes. Acquired hemophilia (AH) is an ultrarare bleeding disorder characterized by factor VIII inhibiting autoantibodies.

Aim

To identify patients with AH using an EHR database.

Methods

Records were accessed from a large EHR database (Humedica) between January 1, 2007 and July 31, 2013. Broad selection criteria were applied using the International Classification of Diseases, Ninth Revision, clinical modification (ICD-9-CM) code for intrinsic circulating anticoagulants (286.5 and all subcodes) and confirmation of records 6 months before and 12 months after the first diagnosis. Additional selection criteria included mention of “bleeding” within physician notes identified via natural language processing output and a normal prothrombin time and prolonged activated partial thromboplastin time.

Results

Of 6,348 patients with a diagnosis code of 286.5 or any subcodes, 16 males and 15 females met the selection criteria. The most common bleeding locations reported was gastrointestinal (23%), vaginal (16%), and endocrine (13%). A wide range of comorbidities was reported. Natural language processing identified chart note mention of “hemophilia” in 3 patients (10%), “bruise” in 15 patients (48%), and “pain” in all 31 patients. No patients received a prescription for approved/recommended AH treatments. Four patient cases were reviewed to validate whether the identified cohort had AH; each patient had bleeding symptoms and a normal prothrombin time and prolonged activated partial thromboplastin time, although none received hemostatic treatments.

Conclusion

In ultrarare disorders, ICD-9-CM coding alone may be insufficient to identify patient cohorts; multimodal analysis combined with in-depth reviews of physician notes may be more effective.

Acquired hemophilia A: a review of recent data and new therapeutic options

OBJECTIVES

Acquired hemophilia A (AHA) is a rare, but potentially life-threatening, bleeding disorder caused by an autoantibody against factor VIII that interferes with its coagulant function.

METHODS

We performed a narrative review focusing on the diagnostic aspects of AHA and on the current treatment strategies with particular regard to new data and therapeutic developments.

RESULTS

The management of this severe hemorrhagic disorder is based on the control of bleeding with the use of bypassing agents and on the utilization of a variety of immunosuppressant agents with the goal of eliminating the autoantibody permanently.

CONCLUSION

The optimal management of AHA should be multidisciplinary and requires a close collaboration between physicians from various specialties.

Diabetes mellitus and acquired haemophilia: new association?

Diabetes mellitus encompasses a group of highly prevalent carbohydrate metabolic disorders with an increasing incidence. Some subtypes are thought to be associated with other immune-mediated diseases. Acquired haemophilia on the other hand is a quite rare autoimmune disease that is thought to be secondary to the emergence of inhibiting anticoagulation factor VIII antibodies (inhibitors) in patients with previously normal haemostatic function. More recently, numerous different diseases have been associated with acquired haemophilia namely immune-mediated diseases, drugs and solid and haematologic neoplasms. The authors report on a case of a patient with new onset acquired haemophilia arising in the setting of diabetic ketoacidosis.

Exsanguinating bleeding following tooth extraction in a 12-year-old girl: a rare case of acquired haemophilia A

Acquired haemophilia A (AHA) is a life-threatening haemorrhagic disorder that occurs with various underlying conditions such as autoimmune disease, drug reactions, lymphoproliferative diseases, solid tumours and pregnancy/postpartum status. However, in half of all reported cases, the underlying disease is unknown. Most AHA cases develop in adults; paediatric/adolescent cases are extremely rare. The main clinical symptom is bleeding into the skin, muscles, soft tissues and/or mucous membranes. Here, we report the case of an otherwise healthy 12-year-old girl who presented with prolonged bleeding postexodontia. After being diagnosed with AHA, she was successfully treated with recombinant activated factor VII infusion and oral prednisolone. To avoid such unanticipated bleeding when performing dental extraction, preoperative haemostatic screening tests are recommended.

Acquired hemophilia A in a patient with advanced prostate cancer

Acquired hemophilia A (AHA) is a rare disorder that results from the presence of autoantibodies against the clotting factor VIII (FVIII) causing hemorrhagic disorders. This entity is mostly associated with autoimmune diseases, pregnancy, the postpartum period, drugs and malignancy. Among the solid cancers, prostate neoplasm is the most common cause of AHA. The management of AHA involves the control of active bleeding and the use of specific therapies to eliminate the inhibitor. The authors describe the case of an 87-year-old man with prostate cancer who developed a bleeding disorder 5 years after the cancer diagnosis. Treatment with prednisone did not reach a satisfactory clinical response, which was only achieved with the association of azathioprine. The patient became asymptomatic with no further bleeding episodes, but developed a fatal sepsis after 3 months of treatment with these immunosuppressive agents.

Acquired hemophilia: a case report and review of the literature

Acquired hemophilia A (AHA) is a rare bleeding disorder caused by autoantibodies against clotting factor VIII (FVIII). FVIII autoantibody is characterized as polyclonal immunoglobulin G directed against the FVIII procoagulant activity. This disease occurs most commonly in the elderly population and with preponderance of men in nonpregnancy-related AHA. There are well-established clinical associations with AHA such as malignancy, other autoimmune diseases and pregnancy. However, up to 50% of reported cases remain idiopathic. The clinical manifestation of AHA includes mostly spontaneous hemorrhages into skin, muscles and soft tissues, or mucous membranes. AHA should be suspected when a patient with no previous history of bleeding presents with bleeding and an unexplained prolonged activated partial thromboplastin time. The diagnosis is confirmed in the laboratory by the subsequent identification of reduced FVIII levels and FVIII inhibitor titration. There is a high mortality, making prompt diagnosis and treatment vitally important. The principles of treatment consist in controlling the bleeding and eradicating the inhibitor. Because of the overall high relapse rate (15-33%), it is also recommended to follow up these patients. The review summarizes what is currently known about the epidemiology, pathogenesis, clinical features, diagnosis, treatment and prognosis of AHA and starts with a case report.

Acquired haemophilia A: the importance of early recognition in cases of spontaneous bleeding in the elderly

We describe the case of a 79-year-old man who presented 'off legs' with acute right leg pain. He was initially treated for suspected cellulitis but subsequently found to have spontaneous soft tissue bleeding into the right thigh. He was eventually diagnosed with idiopathic acquired haemophilia A and treated with activated prothrombin complex concentrates to control acute bleeding followed by immunosuppressant therapy. Acquired haemophilia A is a potentially life-threatening and under-recognised bleeding disorder that results from the immune-mediated development of autoantibodies directed against coagulation factor VIII. The disease is more common in elderly individuals where early recognition and treatment is compounded by the presence of other comorbid conditions, including other potential causes of bleeding. These confounding factors and lack of awareness among non-specialists accounts for the delay in diagnosis that is common in this disease and contributes to the persistently high mortality in this age group.

Anti-factor IXa/X bispecific antibody ACE910 prevents joint bleeds in a long-term primate model of acquired hemophilia A

ACE910 is a humanized anti-factor IXa/X bispecific antibody mimicking the function of factor VIII (FVIII). We previously demonstrated in nonhuman primates that a single IV dose of ACE910 exerted hemostatic activity against hemophilic bleeds artificially induced in muscles and subcutis, and that a subcutaneous (SC) dose of ACE910 showed a 3-week half-life and nearly 100% bioavailability, offering support for effective prophylaxis for hemophilia A by user-friendly SC dosing. However, there was no direct evidence that such SC dosing of ACE910 would prevent spontaneous bleeds occurring in daily life. In this study, we newly established a long-term primate model of acquired hemophilia A by multiple IV injections of an anti-primate FVIII neutralizing antibody engineered in mouse-monkey chimeric form to reduce its antigenicity. The monkeys in the control group exhibited various spontaneous bleeding symptoms as well as continuous prolongation of activated partial thromboplastin time; notably, all exhibited joint bleeds, which are a hallmark of hemophilia. Weekly SC doses of ACE910 (initial 3.97 mg/kg followed by 1 mg/kg) significantly prevented these bleeding symptoms; notably, no joint bleeding symptoms were observed. ACE910 is expected to prevent spontaneous bleeds and joint damage in hemophilia A patients even with weekly SC dosing, although appropriate clinical investigation is required.

Low-dose rituximab in the treatment of acquired haemophilia

OBJECTIVE AND IMPORTANCE

Acquired haemophilia is a rare hemorrhagic disease caused by inhibitory autoantibodies against coagulation factor VIII. Rituximab has become a popular choice for immunosuppressive therapy in acquired haemophilia, almost with the same schedule of 375 mg/m(2) per week for 4-6 doses. While the effect of low-dose rituximab has seldom been reported.

CLINICAL PRESENTATION

We report a patient, aged 88 years, who developed acquired haemophilia with severe hemorrhage and elevation of carbohydrate antigen 125 (CA125), but in the absence of a detectable cause.

INTERVENTION

We prescribed a low-dose rituximab alone (100 mg per week for a total of four infusions) for the patient, different from the conventional usage, but received a similar effect. In addition, the patient was diagnosed with immune thrombocytopenia 22 months after rituximab, while FVIII activity and activated partial thromboplastin time remained within the normal range. After four infusions of low-dose rituximab, the platelet count recovered.

CONCLUSION

At a follow-up of 34 months, the patient remains in remission without further treatment, suggesting low-dose rituximab seems to be a safe and effective regimen for the elderly patients with acquired haemophilia.

Successful treatment of severe lung hemorrhage caused by acquired factor V inhibitor with rituximab

Acquired coagulation factor deficiency is a rare disorder that occurs in patients with drug reactions, malignancy and collagen diseases as well as during pregnancy. Most cases are caused by factor VIII inhibitors. We herein describe the case of a 61-year-old Japanese man with acquired factor V inhibitor who developed symptoms 11 days after lung surgery for empyema. The patient required mechanical ventilation to treat acute respiratory failure due to severe pulmonary hemorrhage. He responded poorly to steroid pulse therapy; however, treatment with rituximab was successful.

Compound heterozygous hemophilia A in a female patient and the identification of a novel missense mutation, p.Met1093Ile

Hemophilia A (HA) in females is rare. Female HA cases are often misdiagnosed as acquired HA (AHA) or as von Willebrand disease type 2N (vWD-2N). Here, we report the case of a 37-year-old female HA patient with a moderate factor VIII (FVIII) deficiency. The patient had no personal or family history of bleeding disorders, but presented with heavy uterine bleeding following surgery to remove an intrauterine device. IgG inhibitory antibodies against FVIII were undetected. A compound heterozygote mutation of the FVIII gene (F8) was found in this patient. The p.Val502Asp mutation, which has been reported previously, affects A2 domain function. A novel missense point mutation, p.Met1093Ile, was identified in the B domain. The compound heterozygote mutations in F8, p.Val502Asp and p.Met1093Ile, caused HA in this female patient, with a moderate phenotype.

Acquired haemophilia A: a 2013 update

Acquired haemophilia A (AHA) is a rare but often severe bleeding disorder caused by autoantibodies against coagulation factor VIII (FVIII). AHA occurs more frequently in the elderly and in association with several conditions, such as the post-partum period, malignancies, autoimmune diseases or drug exposure; however, approximately 50% of reported cases are apparently idiopathic. Beside the elimination of the underlying disorder, the therapeutic approach to AHA should be directed toward the control of acute bleed and the eradication of FVIII autoantibody production. In this narrative review, we summarise the current knowledge on the epidemiology, diagnosis and clinical features of AHA, focusing in particular on advances in the management of this challenging bleeding disorder.

Acquired haemophilia A initially diagnosed as angioedema

Acquired haemophilia (AH) is a bleeding diathesis caused by inhibitors to factor VIII. Patients developing AH may present with catastrophic bleeding episodes despite having no prior history of bleeding disorder. The authors report a patient with AH who presented with tongue swelling and was diagnosed with angioedema on presentation. However, the patient started bleeding spontaneously after presentation and was diagnosed with AH and the workup revealed haematoma of the tongue, which was the cause of tongue swelling. As previously reported in the literature, AH in this patient might have been precipitated secondary to exposure to an ear infection or exposure to the penicillin group of antibiotics. Laboratory examination was confirmatory for AH, which was appropriately treated with recombinant activated factor VIIa and immunosuppressive therapy with good outcomes. Understanding the pathophysiology of AH and appropriate management is important to prevent life-threatening bleeding.

Acquired hemophilia a: retrospective analysis of 49 cases from a single Chinese hemophilia center

Acquired hemophilia A (AHA) is a rare bleeding disorder caused by the autoantibody directed against factor VIII in patients without previous history of a bleeding disorder. We retrospectively analyzed the characteristics and outcomes of 49 patients with AHA diagnosed in our center from February 1994 to October 2012. Twenty-four patients with acute bleeding episodes were treated with prothrombin complex concentrate (PCC) at a relative low dose of 30 to -50 U/kg/d and achieved good outcomes without any adverse reaction. Corticosteroids alone or in combination with cyclophosphamide were used as the first-line therapy to eradicate the inhibitors. In 39 evaluable patients, 35 (89.7%) achieved complete remission (CR). This study demonstrates that when bypassing agents such as recombinant activated factor VII and activated PCCs are not affordable or available, low dose PCC is effective and safe to control acute bleeding in patients with AHA. First-line therapy achieved good outcomes with a CR rate of 89.7%.

Acquired hemophilia in malignancy

Acquired hemophilia is a rare but potentially morbid complication in patients with cancer. It may be seen in patients with hematologic neoplasms (usually lymphoproliferative disorders) or with solid tumors. Although the presence of an underlying malignancy portends a worse outcome, the literature suggests that the usual principles of treatment, including immunosuppression, apply to these patients. However, appropriate consideration should be given to the choice of agents, depending on individual risk factors for complications such as thrombosis and infection.

Macrohematuria as initial presentation in a girl with factor VIII and factor IX inhibitors associated with systemic lupus erythematosus

Acquired hemophilia is rarely observed in a pediatric population. We report a case of a 14-year-old girl presented with ecchymoses and macrohematuria. She developed factor VIII and factor IX inhibitors, and was diagnosed with simultaneous acquired hemophilia and systemic lupus erythematosus (SLE). Recombinant-activated FVII and corticosteroid were prescribed due to macrohematuria-related hypovolemia and anemia, which resolved satisfactorily. This case is a reminder that the rare concurrent presence of factor VIII and factor IX inhibitors could be associated with SLE in a pediatric population. Children with SLE-associated-acquired hemophilia may develop macrohematuria as well.

The IgG autoimmune response in postpartum acquired hemophilia A targets mainly the A1a1 domain of FVIII

BACKGROUND

Acquired hemophilia A (AHA) is a severe life-threatening autoimmune disease due to the development of autoantibodies that neutralize the procoagulant activity of factor VIII (FVIII). In rare cases, AHA occurs in the postpartum period as a serious complication of an otherwise normal pregnancy and delivery. Due to its rarity, little is known about the features of the antibody response to FVIII in AHA.

OBJECTIVES

Our study wanted to (i) determine the epitope specificity and the immunoglobulin (Ig) subclasses of anti-FVIII autoantibodies in plasma samples from a large cohort of AHA patients, and (ii) compare the epitope specificity of anti-FVIII autoantibodies in plasma samples from postpartum AHA and other AHA patients.

PATIENTS/METHODS

Seventy-three plasma samples from patients with postpartum AHA (n = 10) or associated with malignancies (n = 16) or autoimmune diseases (n = 11) or without underlying disease (n = 36) were analyzed with three multiplexed assays.

RESULTS AND CONCLUSIONS

Our results showed a stronger response against the A1a1-A2a2-B fragments of FVIII and more specifically against the A1a1 domain in patients with postpartum AHA than in the other AHA groups (P < 0.01). Moreover, although IgG4 was the predominant IgG subclass in all groups, anti-A1a1-A2a2-B and anti-A1a1 domain autoantibodies of the IgG(1) and IgG3 subclasses were more frequently detected in postpartum AHA than in the other AHA groups. These findings support the involvement of the Th1-driven response in the generation of autoantibodies in women with postpartum AHA compared with the other groups of AHA patients in whom production of Th2-driven IgG4 was predominant.

Acquired haemophilia: an often overlooked cause of bleeding - experience from a Hungarian tertiary care centre

Acquired haemophilia is a potentially life-threatening bleeding disorder. Its early diagnosis and treatment is of major importance. We evaluated the elapsed time between the first presentation of the bleeding symptoms and the correct diagnosis in the cases of the acquired haemophilia patients referred to our centre between 1999 and 2011. The causes and consequences of the often delayed diagnosis were also examined. The clinical and laboratory data of 13 patients with acquired haemophilia were analysed. Eleven patients had inhibitors to factor VIII (FVIII), in one case the autoantibody developed to factor XIII (FXIII) and in one to factor V (FV). The median period between the onset of the bleeding symptoms and the correct diagnosis was 1.5 months (3.0 days-9.0 months). In four cases 4.0-9.0 months were needed to establish the diagnosis. The main reason of this delay was that either the prothrombin time was used exclusively to evaluate haemostasis in primary care and also in some secondary care centres, or the prolonged activated partial thromboplastin time went unnoticed despite the obvious bleeding symptoms. Our observation underlines the importance of early referral of patients with unexplained bleeding symptoms to centres with appropriate laboratory facilities and experience in the diagnosis of bleeding disorders.

Demographic and clinical data in acquired hemophilia A: results from the European Acquired Haemophilia Registry (EACH2)

BACKGROUND

Acquired hemophilia A (AHA) is a rare autoimmune disease caused by autoantibodies against coagulation factor VIII and characterized by spontaneous hemorrhage in patients with no previous family or personal history of bleeding. Although data on several AHA cohorts have been collected, limited information is available on the optimal management of AHA.

OBJECTIVES

The European Acquired Hemophilia Registry (EACH2) was established to generate a prospective, large-scale, pan-European database on demographics, diagnosis, underlying disorders, bleeding characteristics, treatment and outcome of AHA patients.

RESULTS

Five hundred and one (266 male, 235 female) patients from 117 centers and 13 European countries were included in the registry between 2003 and 2008. In 467 cases, hemostasis investigations and AHA diagnosis were triggered by a bleeding event. At diagnosis, patients were a median of 73.9 years. AHA was idiopathic in 51.9%; malignancy or autoimmune diseases were associated with 11.8% and 11.6% of cases. Fifty-seven per cent of the non-pregnancy-related cases were male. Four hundred and seventy-four bleeding episodes were reported at presentation, and hemostatic therapy initiated in 70.5% of patients. Delayed diagnosis significantly impacted treatment initiation in 33.5%. Four hundred and seventy-seven patients underwent immunosuppression, and 72.6% achieved complete remission.

CONCLUSIONS

Representing the largest collection of consecutive AHA cases to date, EACH2 facilitates the analysis of a variety of open questions in AHA.

Inhibitors of propagation of coagulation (factors VIII, IX and XI): a review of current therapeutic practice

The management of patients with congenital haemophilia who develop alloantibodies against factors of the propagation phase of blood coagulation, commonly known as inhibitors, is the most important challenge facing haemophilia caregivers at present, as this complication not only compromises the efficacy of replacement therapy but also consumes an enormous amount of economic resources. Development of inhibitors further complicates the clinical course of severe haemophilia, with a prevalence of up to 30% in patients with haemophilia A (factor VIII deficiency) and up to 5% in those with haemophilia B (factor IX deficiency) and haemophilia C (factor XI deficiency). While the short-term goal of treatment of patients who develop alloantibodies is the control of bleeding, the eradication of the inhibitor is the main long-term goal. The management of severe bleeding episodes and the eradication of the autoantibody are also the mainstays of treatment of patients with acquired haemophilia, a rare but life-threatening haemorrhagic condition characterized by the development of inhibitory autoantibodies against coagulation factor VIII. The most recent options available for treating patients with congenital haemophilia complicated by inhibitors and acquired haemophilia because of autoantibodies against factor VIII are summarized in this review article.

Acquired hemophilia A

Acquired hemophilia A is a rare but often life-threatening hemorrhagic disorder characterized by an autoantibody directed against coagulation factor VIII. Fifty per cent of cases are idiopathic whereas the remaining 50% are associated with pregnancy, autoimmune conditions, malignancies and drugs. In this review the actual knowledge on diagnostic and therapeutic aspects of this disease will be summarized.

Acquired factor V inhibitors: a systematic review

The occurrence of an inhibitor against coagulation factor V (FV) is a rare but challenging condition, which may span from asymptomatic laboratory abnormalities to potentially life-threatening bleeding. The onset of FV inhibitors has been associated most frequently in the past with the patients' exposure to topical bovine thrombin administered during surgery procedures. However, since this preparation is no longer used, in this systematic review we have only focused on non-bovine thrombin-related FV inhibitor cases.

The first case of postpartum acquired hemophilia A in Korea

Acquired hemophilia A (AHA) is a rare coagulopathy caused by autoantibodies to coagulation factor VIII (FVIII). Most patients with AHA have been previously healthy; however, a variety of morbidities have been associated with the condition including pregnancy. A 40-yr-old woman visited our institution with extensive hematoma on the right hip area. Her medical history revealed no personal or familial history of bleeding diathesis. Her coagulation tests showed markedly prolonged aPTT (117 sec), markedly decreased level of FVIII activity (0.4%) and high-titer FVIII inhibitor (77 BU). Collectively, she was diagnosed as having postpartum AHA and was treated with bypassing agents and corticosteroids. Her aPTT was normalized on the 174 th postpartum day and FVIII inhibitor showed negative conversion on the 224 th postpartum day. This is the first case of postpartum AHA with high-titer FVIII inhibitor in Korea. Timely diagnosis and management can reduce morbidity and mortality of this potentially life-threatening condition.

Acquired hemophilia a: diagnosis, aetiology, clinical spectrum and treatment options

Acquired hemophilia A (AHA) is a rare disorder with an incidence of approximately 1 per million/year with a high mortality rate of more than 20%. The disease occurs due to autoantibodies against coagulation factor VIII (FVIII) which neutralize its procoagulant function and result in severe, often life-threatening bleeding. The antibodies arise in individuals with no prior history of hemophilia A. AHA may be associated with pregnancy, autoimmune diseases, malignancy, infections or medication and occurs most commonly in the elderly. Approximately 50% of the patients remain idiopathic with no known underlying pathological condition. Clinical manifestations include spontaneous hemorrhages into the skin, muscles or soft tissues or excessive bleeding during surgery. Hemarthrosis which is the hallmark of congenital severe hemophilia A seldom occurs in AHA. The diagnosis of AHA is based on the isolated prolongation of activated partial thromboplastin time (APTT) which does not normalize after the addition of normal plasma along with reduced FVIII levels. The treatment involves two aspects-eradication of antibodies and maintaining effective hemostasis during a bleeding episode. The protocols for eradication of antibodies include immunoadsorption, immunosuppression or immune tolerance induction (ITI). The treatment of acute bleeding episodes involves use of different bypassing agents like recombinant activated factor VIIa (rFVIIa, NovoSeven®) and activated prothrombin complex concentrate (aPCC, (FEIBA®) in case of patients with high titer inhibitors or with antifibrinolytics,1-deamino-8-D-arginine vasopressin (DDAVP) or FVIII concentrates in low titer inhibitor patients. The anti CD20 monoclonal antibody, rituximab, has shown very good results either singly or in combination with immunosuppressive regimens in patients who do not respond to standard immunosuppressors. The present review summarizes the diagnostic, aetiological, clinical and treatment aspects of AHA focusing on the recent advances in this area.

Acquired hemophilia in pediatrics: a systematic review

Acquired hemophilia A is a rare but potentially life-threatening hemorrhagic disorder caused by the development of autoantibodies directed mostly against coagulation factor VIII. Acquired hemophilia is frequently associated with several underlying conditions such as malignancy, autoimmune disorders, drug reactions, and pregnancy, although the pathogenesis remains undetermined (idiopathic) in up to 50% of reported cases. The disorder occurs most commonly in the elderly and only rarely affects pediatric patients, who might however experience severe, and sometimes life-threatening, hemorrhage. The maternal transplacental transfer of the autoantibody to the neonate occurs very rarely and also in this circumstance it may be associated with clinically significant bleeding. The management of acute bleeding and the inhibitor eradication are the mainstay of the treatment. The outcome in pediatric patients seems more favorable than in adults because the inhibitors usually resolve more quickly and in a higher rate of patients. The epidemiology, diagnosis, clinical course, and management of this hemorrhagic disorder in children will be addressed in this systematic review.

Diagnosis, laboratory aspects and management of acquired hemophilia A

Acquired hemophilia A (AHA) is a rare autoimmune disease, characterized by severe, often life-threatening hemorrhages in patients without a prior history of bleeding disorder. It most frequently occurs in the elderly, and may be associated with other clinical conditions, such as cancer, autoimmune diseases, pregnancy or without a relevant cause. Diagnosis and correct therapy are crucial for the patient's outcome. Management of the disease consists of gaining immediate control of acute bleeding and the starting of an immunosuppressive therapy in order to eradicate the anti-factor VIII autoantibody. Factor VIII bypassing agents, such as prothrombin complex concentrates or recombinant activated factor VII, have proven effective in bleeding control, whereas the combined therapy of cyclophosphamide and corticosteroids seems to be, at present, the best immunosuppressive option. Other treatments including Rituximab, immunoadsorption or induction of immune tolerance are still experimental, and need to be validated through controlled clinical trials.

The laboratory approach to inherited and acquired coagulation factor deficiencies

Besides the long-recognized hemophilias, there are many other factor deficiencies. Some also are inherited, but others are acquired because of both immune and nonimmune etiologies. Understanding the optimal laboratory approach to evaluating factor deficiency will aid physicians and laboratory scientists in obtaining a prompt diagnosis and in avoiding pitfalls in coagulation testing.