Management of bleeding disorders in children

Haemophilia, if not properly managed, can lead to chronic disease and lifelong disabilities. The challenges and issues in infants/young children are different from those in older children and adults although episodes of bleeding still predominate as the diagnostic trigger. Awareness of clinical manifestations and treatment complications are crucial in instituting appropriate management and implementing preventive strategies. Currently, inhibitor development is a challenging complication of paediatric haemophilia and prophylaxis is emerging as the optimal preventive care strategy. In this section we will review some important aspects of haemophilia in children including early prophylaxis, current evidence relating to inhibitor development, including the aims of the SIPPET study which is already ongoing and involves boys <6?years, and the potential of immune tolerance therapy for eradicating the inhibitor and permitting a resumption of standard dosing schedules.     

Management of bleeding disorders in the elderly

We are entering a new phase in the management of patients with bleeding disorders such as haemophilia. This is the result of the positive effects that disease management strategies have had on patient longevity over the last 10-15 years. A greater number of individuals are entering middle- to old-age and, as a result, we face a new era of having to manage haemophiliac patients at risk of, or suffering from, age-related diseases. We can clearly learn from the experiences of geriatricians who have made many advances in the management of chronic disorders such as cardiovascular diseases and osteoporosis. However, the hypocoagulable state brings challenges of its own and it is important that we communicate our experiences so that the shared information can help drive improved levels of care and better clinical outcomes. In this article we look at factors that have impacted the life expectancy of patients with haemophilia over the last few decades, and we also review some of the early literature relating to cardiovascular risk management and the treatment of osteoporosis.     

Management of orthopaedic surgery in rare bleeding disorders

Knowledge regarding the management of orthopaedic surgery in patients with rare bleeding disorders (RBDs) is limited. Retrospective data collection and analysis of 35 orthopaedic procedures (6 minor and 29 major) carried out in 22 patients with RBD between 1982 and 2013. These surgeries were performed using heterogeneous regimens of hemostatic therapy, except for seven procedures performed with no hemostatic treatment in four patients with mild factor deficiency. Of the 28 procedures carried out with hemostatic treatment, nine (32%) were performed using replacement therapy with dosages of concentrates of the deficient factor aimed to achieve perioperative plasma levels judged to be compatible with hemostasis; three (11%) using factor replacement therapy associated with fresh frozen plasma (FFP); four (14%) using recombinant activated factor VII; four (14%) using virus inactivated plasma alone; three (11%) using virus inactivated plasma associated with desmopressin; one (4%) using FFP alone; and four (14%) procedures using tranexamic acid alone. Bleeding complications occurred in 7 of 35 procedures (20%) involving five patients. Prophylaxis of venous thromboembolism was performed only in one case with no excessive bleeding, but two patients not on thromboprophylaxis developed superficial thrombophlebitis. A satisfactory control of hemostasis was achieved in most patients. In some of those characterized by mild factor deficiency (FVII, FXI) hemostatic treatment could be avoided in some instances. The control of hemostasis combined with an adequate surgical technique is needed for the successful outcome of orthopaedic surgery in RBDs that requires the involvement of specialized haemophilia centres.     

Management of bleeding disorders: basic science

Development of factor VIII (FVIII) inhibitors is the most severe and challenging complication of haemophilia A treatment and represents the highest economic burden for a chronic disease. Therefore, major research efforts are ongoing to optimize the therapeutic approaches able to minimize this complication. FVIII inhibitors have variable immuno-reactivity against different FVIII concentrates and generally have a lower reactivity against von Willebrand factor (VWF)-containing FVIII concentrates than plasma-derived FVIII (pdFVIII) or recombinant FVIII (rFVIII) that are devoid of VWF, in particular when the inhibitors are directed against the light chain of FVIII. This paper provides an overview of several in vitro and in vivo studies that compared three clinically available clinical FVIII products (Kogenate?, Bayer AG, Leverkusen, Germany; Advate?, Baxter Healthcare, Zurich, Switzerland; and Fanhdi?, Grifols S.A., Barcelona, Spain) in order to evaluate the functional actvity of the FVIII fractions in rFVIII that cannot bind VWF; explore the use of the thrombin generation assay (TGA) as a potential tool for optimizing the choice of FVIII concentrate for use in haemophilia A patients with inhibitors; compare the kinetics of the interactions between anti-FVIII antibodies and FVIII both in the presence/absence of VWF, using surface plasmon resonance.     

Management of bleeding disorders by prohemostatic therapy

Pro-hemostatic therapy aims at an improvement of hemostasis, which may be achieved by amelioration of primary hemostasis, stimulation of fibrin formation or inhibition of fibrinolysis. These treatment strategies may be applied to specifically correct a defect in one of the pathways of coagulation, but have in some situations also been shown to be effective in reducing bleeding in patients without a primary defect in coagulation. Besides the transfusion of platelets in case of thrombocytopenia or severe platelet disorders, a pharmacological improvement of primary hemostasis may be achieved by the administration of desmopressin. The administration of DDAVP results in a marked increase in the plasma concentration of Von Willebrand factor (and associated coagulation factor VIII) and (also by yet unexplained additional mechanisms) a remarkable potentiation of primary hemostasis as a consequence. DDAVP is used for the prevention and treatment of bleeding in patients with von Willebrand disease or mild hemophilia A, and further in patients with an impaired function of primary hemostasis, such as in patients with uremia, liver cirrhosis or in patients with aspirin-associated bleeding. Based on the current insight that activation of coagulation in vivo predominantly proceeds by the tissue factor/factor VII(a) pathway, recombinant factor VIIa has been developed as a prohemostatic agent and has recently become available for clinical use. Indeed, in uncontrolled clinical studies this compound has been shown to exert a potent procoagulant activity and appeared to be highly effective in the prevention and treatment of bleeding, although most experience so far has been obtained in patients with severe and complicated coagulation defects. At present, a more general use of this agent for bleeding patients without an apparent coagulation defect is the subject of a number of ongoing clinical trials. Agents that exert anti-fibrinolytic activity are aprotinin and the group of lysine analogues. The pro-hemostatic effect of these agents proceeds not only by the inhibition of fibrinolysis (thereby shifting the procoagulant/anticoagulant balance towards a more procoagulant state), but also due to a protective effect on platelets, as has been demonstrated at least for aprotinin. The mechanism of this platelet-protective effect has, besides a potential prevention of plasmin-mediated loss of platelet receptors not been elucidated. Whether the pro-hemostatic effect of the anti-fibrinolytic agents will eventually result in a higher incidence of thromboembolic complications is still a matter of debate (see further), however, this has so far not been shown in straightforward clinical trials.     

Haemorrhagic complications with adenotonsillectomy in children and young adults with bleeding disorders

Haemorrhagic complications remain a challenge with surgical procedures in patients with bleeding disorders. In children and young adults, the most commonly performed surgeries are tonsillectomies and/or adenoidectomies. Adequate haemostasis in these patients with bleeding disorders is centred on comprehensive perioperative haemostatic support and dexterous surgical technique. The aim of this study was to assess postoperative bleeding complications with tonsillectomy and/or adenoidectomy in children and young adults with known bleeding disorders. Retrospective review of all patients aged <25 years with known bleeding disorders who underwent tonsillectomy and/or adenoidectomy at Mayo Clinic, Rochester MN between July 1992 and July 2012. In contrast to reported literature, we observed a higher rate of bleeding complications (10/19, 53%) despite aggressive haemostatic support and appropriate surgical techniques. Delayed bleeding (>24 h postoperatively) was more common than early bleeding; and recurrent bleeding was associated with older age. Children and young adults with haemorrhagic diatheses undergoing adenotonsillectomy are at a higher risk of delayed bleeding and require close monitoring with haemostatic support for a prolonged duration in the postoperative period. A uniform approach is needed to manage these patients perioperatively by establishing standard practice guidelines and ultimately reduce postsurgical bleeding complications.     

Rare bleeding disorders

Summary.  During the haemostatic response, the formation of a primary platelet plug limits bleeding and provides a surface for clotting factors to assemble and become activated. The initial platelet plug is stabilized by fibrin monomers, covalently cross-linked by FXIII, forming a platelets-fibrin thrombus. Defects in platelets as well as inherited deficiencies of coagulation factors including fibrinogen, FII, FV, FV + FVIII, FVII, FX, FXI and FXIII deficiencies, generally lead to lifelong bleeding disorders, whose severity of bleeding symptoms is heterogeneous in platelets abnormalities but generally inversely proportional to the degree of the factor deficiency in rare bleeding disorders (RBDs). The prevalence of platelet defects among the general population has not been established, whereas for RBDs it ranges from approximately 1 in 2 million to 1 in 500 000, being higher in countries where consanguineous marriages are diffused. As a consequence of the rarity of these deficiencies, the type and severity of bleeding symptoms, the underlying molecular defects, and the actual management of bleeding episodes are not well established. In this review the main features, diagnosis, available treatment options and treatment complications of the platelet disorders, caused by abnormalities in platelet receptors for adhesive proteins, platelet receptors for soluble agonists, platelet granules, signal transduction pathways, or procoagulant phospholipids will be discussed by Dr Cattaneo, whereas fibrinogen deficiency and FXIII deficiency will be described by Dr Inbal and Dr de Moerloose, respectively. Finally, the update of the Rare Bleeding Disorders Database will be presented by Dr Spreafico.     

Rare bleeding disorders

Summary.  Deficiencies of coagulation factors other than factor VIII and factor IX (afibrinogenemia, FII, FV, FV+FVIII, FVII, FX, FXI, FXIII) that cause bleeding disorders (RBDs) are inherited as autosomal recessive traits and are rare, with prevalences in the general population varying between 1 in 500.000 and 1 in 2 million for the homozygous forms. As a consequence of the rarity of these deficiencies, the type and severity of bleeding symptoms, the underlying molecular defects, and the actual management of bleeding episodes are not as well established as for hemophilia A and B. The study of the genetic basis of these disorders could represent an important tool for prevention through prenatal diagnosis. Treatment of patients with RBDs during bleeding episodes or surgery is a challenge because of the lack of experience and the paucity of data. For some deficiency factor concentrates are still non available and severe complications can occur. These complications can be minimized by assessment of risks of bleeding and thrombosis, use of haemostatic means other than blood components or no therapy at all. The RBDs pose a problem for guideline writers because there are no suitable clinical trials to supply good evidence for how these people are best treated. The lack of adequate information on clinical manifestations, treatment and genetic basis of RBDs could be improved by the collection of data in an International Database ( http://www.rbdd.org ), linkable to others previously published. This could be a useful tool to fill the gap between clinical data and clinical practice. This article reviews the genetic basis of RBDs, problems and complications of treatment, problems in the preparation of suitable guidelines for treatment and the future perspectives of the International Registry on RBDs.     

Gastrointestinal bleeding in older adults

Gastrointestinal bleeding in older adults is a frequent cause of hospital admissions. The presence of multiple comorbidity conditions and greater medication use in this age group influence the clinical outcome. The selection of diagnostic and therapeutic maneuvers often depends more on local expertise and availability. This article addresses clinical presentation, etiology, diagnosis, and treatment of upper and lower gastrointestinal bleeding in elderly individuals.     

Thrombosis in rare bleeding disorders

Inherited deficiencies of blood coagulation factors are usually associated with lifelong bleeding tendency. In addition to Haemophilias A and B and von Willebrand disease, congenital deficiencies of such factors as fibrinogen, prothrombin (FII)), FV, FVII, FX, FXI, FXIII, and combined deficiencies occur and can lead to a diversity of clinical conditions. Paradoxically, for some of these disorders associated with significant bleeding tendency there are reports of thrombotic events, both arterial and venous. Thrombosis in hemophilia patients has a multifactorial pathogenesis and the main conditions associated with this complication are the use of long-term central venous catheters, intensive replacement therapy usually in the setting of surgical procedures, the use of bypassing agents or the coexistence of acquired or inherited prothrombotic risk factors. Regarding other rare bleeding disorders, thrombotic phenomena has been described particularly in patients with afibrinogenemia, FXI and FVII deficiency and the events can occur even in young patients, in the presence of concomitant risk factors or spontaneously. Replacement therapy must be individualized and should take into account past history of haemostatic challenges, family history of bleeding and thrombosis, just like the level of factor. For mild deficiencies when patients are asymptomatic the use of antithrombotic prophylaxis must be considered with or without concomitant use of replacement therapy. In patients with history of thrombosis it may be helpful to perform a thrombophilia screening to exclude coexisting prothrombotic defects and for all patients it is recommended to control known cardiovascular disease risk factors.     

Laboratory issues in bleeding disorders

Summary.  The clinical history of the patient and of his/her relatives is the most important tool for making correct diagnosis of inherited or acquired bleeding disorders. Several attempts have been made by clinicians to evaluate the sensitivity and specificity of bleeding symptoms. Specific and detailed questionnaires have been designed to quantify the bleeding tendency of patients with von Willebrand's disease (VWD) and a bleeding score has been calculated. VWD is considered the most frequent inherited bleeding disorder according to population studies: however, due to the complexity of its diagnosis, the number of patients with correct diagnosis of VWD in many developing countries is relatively low and most cases remain still under- or misdiagnosed. Once bleeding history is carefully evaluated by means of a bleeding score, the laboratory workout should be organized to find out the specific defect of haemostasis responsible for bleeding. Since factors involved in haemostasis are many, the correct approach must include first level screening tests with the aim to identify the abnormal phase of haemostasis involved: then, second level tests should be focused on the specific factors within the abnormal step of haemostasis. Among many other acquired bleeding disorders related to clinical conditions or to the use of drugs, the acquired inhibitors of haemostasis are rare but should be immediately characterized by appropriate laboratory tests because they can be often life-threatening for the patients.     

Laboratory issues in bleeding disorders

Summary.  Selected laboratory issues critical for the appropriate diagnosis of haemophilia A and B, von Willebrand's disease (VWD) and more rare bleeding disorders (RBD) are discussed from a worldwide perspective. The overall picture that emerges is on the whole reassuring. Even in non-Western countries like Latin America, most cases of haemophilia are appropriately diagnosed. Moreover, national and international laboratory training workshops are further improving the diagnostic capabilities also in less severe disorders. Most of the RBD can be appropriately diagnosed with relatively simple tests wherever a high clinical suspicion is present. Moreover, minimal requirements for a useful clinical diagnosis are not too far from the capabilities of majority of non-Western countries. The most needed areas concern VWD and platelet function disorders, which suffer from inadequate diagnostic standardization, hampering widespread diagnostic capability in both Western and non-Western countries.     

Heavy menstrual bleeding in women with inherited bleeding disorders

Heavy menstrual bleeding (HMB) is the commonest bleeding symptom among women with inherited bleeding disorders (IBD). Since HMB starts at the very onset of menarche and continues throughout the reproductive life, the health related quality of life of these women is affected and they are at an increased risk of developing iron‐deficiency anemia. Because of the entrenched stigma and taboos, women and girls are often reluctant to discuss the problem of HMB within their families and do not seek medical advice. Increased awareness and multidisciplinary management approach for the management of these women are essential in ensuring an optimal outcome. It is important to take a careful history and undertake a thorough gynecological assessment to exclude other underlying/concomitant causes of HMB. Iron supplementation is essential. Strategies for decreasing menstrual blood flow are similar to those used for HMB in general with the addition of desmopressin and replacement therapy and the exclusion of non‐steroidal anti‐inflammatory drugs. Tranexamic acid and/or hormonal intervention are usually recommended as first‐line therapy. Treatment choice should be individualized taking into account whether the woman wishes to preserve her fertility, if she requires contraception, the type of IBD, the severity of bleeding, and her social and religious background as well as acceptability and availability of the treatment options.