Unresolved issues in diagnosis and management of inherited bleeding disorders in the perinatal period: A White Paper of the Perinatal Task Force of the Medical and Scientific Advisory Council of the National Hemophilia Foundation, USA

Identification of the Intron 22 and Intron 1 Inversions of the Factor VIII Gene in Iraqi Kurdish Patients With Hemophilia A

Hemophilia A (HA) is a severe coagulation disorder affecting 1 in 5000 to 10 000 male births. In severe cases, the most deleterious large DNA rearrangements are inversions of intron 22 (Inv22) and intron 1 (Inv1) of the factor VIII (FVIII) gene. These account for 40% to 50% and 1% to 5% of all causative mutations, respectively. Nevertheless, no genetic analysis to identify the actual causative mutation of FVIII, particularly Inv22 and Inv1, among Iraqi Kurdish hemophiliacs has been performed. In this study, we aimed to genotype Inv22 and Inv1 of the FVIII gene in our patients with HA and reveal the genotype/phenotype correlation with the inversion mutations and their role as a risk factor for the development of inhibitors. Analyses of the Inv22 and Inv1 mutations in 80 Iraqi Kurdish patients with HA (60 severe, 18 moderate, and 2 mild) were performed using the inverse shifting–polymerase chain reaction (IS-PCR) method. In severe cases, 46.7% (28/60) had Inv22 and 3.3% (2/60) had Inv1. The genotype/phenotype relation of Inv22 and Inv1 illustrated a statistically significant association (P = .012) between disease severity and inversion mutations. Slightly more patients with Inv22 (39%) developed inhibitors than those without Inv22 (28%; odds ratio = 1.65, 95% confidence interval = 0.56-4.87, P = .361). Inv22 is a major cause of severe HA in Iraqi Kurdish patients, and IS-PCR is a rapid, robust, and effective method that can be applied for carrier detection and prenatal diagnosis of HA in developing countries.

Prenatal diagnosis in rare bleeding disorders-An unresolved issue?

Intracranial haemorrhage (ICH) is the most dreadful complication, and the main cause of death among patients with rare bleeding disorders (RBD) and prenatal diagnosis (PND) is a preventative lifesaving program. A total of 39 PNDs were reported in the literature through a search on PubMed, EMBASE, SCOPUS and Web of Science databases, most often for congenital factor (F) XIII and FVII deficiencies and rarely in FX, FV deficiencies and afibrinogenemia. The main cause to request a PND is ICH and related morbidity and mortality. Different molecular methods including direct sequencing and linkage analysis as well as polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) for a specific mutation are the most common used methods for PND, while factor assay and combination of molecular and factor assay also were used. In this research, 7 severely affected foetuses were identified during PND including 3 foetuses with FXIII deficiency, 3 with FVII deficiency and 1 with FX deficiency. Out of these 7 cases, intrauterine ICH occurred in 1 case with FXIII deficiency, 1 was electively aborted and 1 case with severe FVII deficiency received intrauterine factor transfusion. Postdelivery ICH was reported for 1 patient with severe FVII deficiency within the first month of life. All other pregnancies were uneventful.

Evolution of the Treatments for Hemophilia

Although hemophilia has been recognized for centuries as an inherited disorder primarily affecting males, advances in treatments have been very recent. Initial availability of plasma-derived therapies offered significant improvements in morbidity and mortality, but the transmission of viruses quickly negated the benefit of early factor replacement products. After developing successful viral inactivation methods and subsequently developing recombinant technology, the manufacturing of factor concentrates became much safer. Access to safer factor products allowed for a shift from the treatment of bleeds to prevention, called prophylaxis. Although dosing and interval vary, prevention of joint disease is now a realistic goal. Unfortunately, despite advances in the safety of therapy, some patients are unable to use factor replacement products because they develop antibodies, known as inhibitors. Eradication of inhibitors is possible in the majority of patients, but it is expensive and takes time. Management of acute bleeding may require significantly higher doses of factor replacement or the use of a bypassing agent. As a result, patients with inhibitors are at increased risk for sequelae, including joint disease, life-threatening bleeding, infectious complications with central vascular access devices, and thrombotic complications.

Perinatal aspects of haemophilia

Haemophilia is an X-linked recessive genetic disease of haemostasis. Women carriers may present with a bleeding tendency similar to milder forms of the disease. Haemophilic newborns present risk factors and patterns of bleeding that are challenging. Identification of carriers and genetic counselling before conception is considered optimal to help decide on available conception options and during pregnancy to help minimise bleeding risks for both carrier mother and affected baby. Preimplantation genetic diagnosis is attractive to many couples at risk of having a child with haemophilia and relevant technology is becoming more available although it has both practical and ethical limitations. Pregnancy in carriers should be managed by a multidisciplinary team in a comprehensive treatment centre. The optimal mode of delivery for carriers expecting a baby known to have or being at risk of haemophilia is an issue of great debate. The general consensus among authors is avoidance of instrumental delivery, foetal scalp electrodes and blood sampling in pregnancies at risk of carrying an affected foetus, as well as early recourse to Caesarean section as guided by obstetric indications. Intracranial haemorrhage, although infrequent, is one the most devastating types of bleeding in haemophilic newborns and can occur regardless of the mode of delivery or the severity of haemophilia. Early screening is proposed for all infants with severe or moderate haemophilia who have had traumatic delivery and/or have evidence of extracranial haemorrhage. Women with postpartum haemorrhage should have a bleeding work-up.

Prenatal diagnosis in haemophilia A: experience of the genetic diagnostic laboratory

The paper describes the experience of the Genetic Diagnostic Laboratory in prenatal testing for haemophilia A, an X-linked recessive disease caused by mutations in the F8 gene. Knowledge of a familial mutation prior to pregnancy can benefit prenatal diagnosis and decrease wait time for molecular testing during pregnancy. This is a retrospective review of a series of pregnant women who pursued F8 gene testing from December 1997 through May 2012, highlighting three cases, which demonstrate the technical complexities of analysis and the implications of not knowing carrier status prior to pregnancy. Mutations of the F8 gene were detected in affected males, obligate female carriers and suspected female carriers by DNA sequencing, inverse-PCR, qRT-PCR, Southern blot and exonic dosage analysis. The same methods were used to analyse prenatal samples from obligate or suspected female carriers upon request. Maternal cell contamination studies were performed for all prenatal samples analysed. Ninety-nine women pursued F8 testing during pregnancy, either for carrier status alone or carrier status and prenatal diagnosis. Ninety-one women (91%) requested carrier testing because they did not know their F8 mutation carrier status prior to pregnancy. Eight women requested prenatal diagnosis only, and only 4 of these were aware of their mutation status. Thirty-seven individuals were found to be mutation carriers. Forty-two prenatal samples were received for prenatal diagnosis. In total 21 foetuses were identified as mutation carriers. Mutation detection was complex and increased the turnaround time in some cases. Only four of 99 women who submitted samples for F8 testing were aware of their F8 mutation status prior to pregnancy. Knowledge of F8 mutation status prior to pregnancy allows for efficient prenatal diagnosis, when desired. Thus, preconception genetic counselling is required to inform patients of the available options and the complex and time-consuming nature of F8 testing.

Three cost-utility analyses of screening for intracranial hemorrhage in neonates with hemophilia

BACKGROUND

Intracranial hemorrhage (ICH) in the newborn period is a potential cause of serious morbidity and mortality in individuals with hemophilia. The incidence of ICH is estimated to be 2% to 4%; however, depending on the mode of delivery, it may be considerably higher. Considering the varying sensitivities and costs of various imaging modalities, there remains controversy surrounding universal cranial imaging. Cost-utility analysis is the ideal tool to display the consequences of a decision made.

METHODS

We constructed a decision tree to evaluate the direct and indirect costs, possible outcomes, and probabilities of ICH in neonates with hemophilia. We created 3 decision analysis models to evaluate the cost-utility of different screening modalities for ICH: ultrasound, computed tomography, and magnetic resonance imaging. Within each model, 3 different strategies were compared: screen all neonates; screen only neonates born by instrumented delivery; and not screen any neonates. A societal perspective was used for all models. The base case models were later reanalyzed in sensitivity analysis to account for uncertainties.

RESULTS

Total costs for screening all neonates, screening only neonates born by instrumented delivery, and not screening any neonates were $9501, $9297, and $9347, respectively, for US, and $9761, $9351, and $9353, respectively, for CT. Screening instrumented deliveries using MRI had an incremental cost-effectiveness ratio of $12,440.

CONCLUSIONS

Screening newborns born by an instrumented delivery appears to be the most cost-effective strategy irrespective of the imaging modality. Subsequent studies will require a longer time frame to factor in possible late effects of radiation, anesthesia, and the high cost of factor replacement and hospital admission.

Haemophilia in extreme immature preterm infants: increased risk for intracranial haemorrhage?

Haemophiliacs and extremely premature infants are both at an increased risk for intracranial haemorrhage; both conditions might be further elevating the risk. We report a case of a very immature preterm-infant of 26 gestational weeks (birth weight 635 g) with severe haemophilia A. Furthermore, we provide an overview of the published literature on this subject matter. Until now, deficiency of factor VIII or IX as a potential risk factor for ICH in preterm infants remains controversial. However, prophylactic substitution of factor VIII or IX in preterm infants with haemophilia may minimize the risk of bleeding complications and neurologic sequelae.

Pharmacotherapy of haemophilia A

INTRODUCTION

Haemophilia A is due to factor VIII (FVIII) deficiency. The main treatment is replacement therapy with FVIII concentrates. However, these concentrates carried a high risk of blood-borne viral infections and still have a high risk of inducing anti-FVIII inhibitors.

AREAS COVERED

An overview of products available and therapeutic options for haemophilia A management in order to help in decision making. A literature search using Medline with the keywords: 'haemophilia', 'factor VIII', 'therapy', 'inhibitor', 'concentrate', 'bleeding', 'prophylaxis', 'on demand', 'plasma-derived', 'recombinant', 'coagulation factors', 'immunotolerance' was performed. The years 1960 - 2010 are included.

EXPERT OPINION

Progress in management of patients with haemophilia A has allowed increased life expectancy and quality of life. There is evidence that prophylaxis prevents or, at least, slows down arthropathy development when started early in childhood. FVIII concentrates have achieved high levels of blood-borne pathogen safety. However, treatment is frequently complicated by development of FVIII-neutralizing inhibitors, which prevent control of bleeding and predispose to a high morbidity and mortality risk. Bypassing agents are effective in bleeding treatment in a high percentage of cases. Prophylaxis with bypassing agents and their use in combination are offering opportunities in management of inhibitor patients. More evidence is necessary to understand how to prevent and manage this complication.

Genotyping of intron 22-related rearrangements of F8 by inverse-shifting PCR in Egyptian hemophilia A patients

Hemophilia A (HA) is the most common severe bleeding disorder in humans, affecting one in 5,000 male births. In severe HA, intron 22 inversion of F8 is the most prevalent mutation, accounting for 40-50% of all mutations; however, little is known about the disease-causing mutations among Egyptian hemophiliacs. We aimed at genotyping all possible known DNA rearrangements of intron 22 of F8 in Egyptian HA patients. Peripheral blood samples were collected from 30 Egyptian HA patients (13 severe, ten moderate, and seven mild cases). Genotyping of F8 intron 22 rearrangements was performed by inverse-shifting PCR (IS-PCR). Our study revealed that seven patients (23.3%) had inversion 22, three patients (10%) had deletion 22, and 20 patients (66.7%) carried the wild-type allele. No intron 22 duplication was detected. The relative proportion of inversion 22-type 1 to inversion 22-type 2 was 85.7% and 14.3%, respectively, whereas the relative proportion of deletion 22-type 1 to deletion 22-type 2 was 33.3% and 66.7%, respectively. A statistically highly significant relation was found between disease severity and F8 intron 22 rearrangements (p = 0.008). Among severe cases, 46.1% had inversion 22, 23.1% had deletion 22, and 30.8% carried the wild-type allele. We conclude that F8 intron 22 inversion/deletion is responsible for about one third of disease-causing mutations among Egyptian hemophiliacs and for nearly 70% in severe cases. In addition, F8 intron 22 inversion/deletion by IS-PCR has proven to be a rapid and robust technique and might be the recommended tool for genetic analysis of HA patients specially with severe cases in developing countries.

Splenic rupture in a newborn with severe hemophilia--case report and review

Life-threatening splenic rupture is rare in neonates with severe hemophilia. There are only 3 cases of splenic rupture in neonates with hemophilia reported in the literature. We present the case of an infant, born to a hemophilia A carrier mother. The infant was asymptomatic until discharge at 48 hours of age, but presented on the third day of life with shock, abdominal distension, and severe anemia. Computed tomography of the abdomen confirmed the diagnosis of splenic rupture with hemoperitoneum. The infant recovered after extensive supportive care surgery and factor replacement.

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.

Sites of initial bleeding episodes, mode of delivery and age of diagnosis in babies with haemophilia diagnosed before the age of 2 years: a report from The Centers for Disease Control and Prevention's (CDC) Universal Data Collection (UDC) project

Lack of detailed natural history and outcomes data for neonates and toddlers with haemophilia hampers the provision of optimal management of the disorder. We report an analysis of prospective data collected from 580 neonates and toddlers aged 0-2 years with haemophilia enrolled in the Universal Data Collection (UDC) surveillance project of the Centers for Disease Control and Prevention (CDC). This study focuses on a cohort of babies with haemophilia whose diagnosis was established before the age of two. The mode of delivery, type and severity of haemophilia, onset and timing of haemorrhages, site(s) of bleeding, provision of prophylaxis with coagulation factor replacement therapy, and the role played by the federally funded Haemophilia Treatment Centers (HTC) in the management of these infants with haemophilia were evaluated. Seventy-five per cent of haemophilic infants were diagnosed early, in the first month of life, especially those with a family history or whose mothers were known carriers; infants of maternal carriers were more likely to be delivered by C-section. Involvement of an HTC prior to delivery resulted in avoidance of the use of assisted deliveries with vacuum and forceps. Bleeding from the circumcision site was the most common haemorrhagic complication, followed by intra- and extra-cranial haemorrhages and bleeding from heel stick blood sampling. Eight per cent of the infants were administered factor concentrate within 24 h of birth; more than half were treated to prevent bleeding. This study highlights the significant rate and the sites of initial bleeding unique to very young children with haemophilia and underscores the need for research to identify optimal evidence-based recommendations for their management.

Management of carriers and babies with haemophilia

Although up to 30% of babies born with haemophilia do not have a family history of the disorder, the remaining 70% are born in families where haemophilia has been diagnosed. It has been estimated that for each male with haemophilia, there are five potential female carriers. Such women will benefit from knowledge of both their genetic (mutation present or not) and phenotype (level of plasma factor activity) status. Genetic counselling services to provide information and testing, together with plasma factor measurement, should be offered where available to all women at risk of being carriers. It is critical that women know their plasma factor measurement as they may have mild haemophilia (factor 5-30%, reference range 50-150%) which requires management at times of medical and surgical procedures and following trauma. Close liaison between adult and paediatric haemophilia centres and obstetric-gynaecology units is important to ensure that clinical carers identify and address carriers' needs. Genetic testing should be performed only after a potential carrier has been counselled and supported to receive such information. There is no coercion to accept such testing. An advantage of genetic testing is to then discuss pre-implantation genetic diagnosis which is an ex-vitro form of prenatal diagnosis. This can assist couples at risk of having a child with haemophilia who wish to reduce their anxieties about reproduction. Approximately 4% of boys with haemophilia, born in countries with good maternal care, will have intracranial haemorrhage in the neonatal period. There are no high-level evidence-based guidelines for the management of delivery or of the newborn with haemophilia. Obstetricians or other birth attendants need to be advised of the possibility of delivery of a boy with haemophilia and seek support from a haemophilia specialist during the pregnancy. The mother can then be monitored and plans for delivery be developed between her medical consultants and discussed with her. It is always preferable for a carrier to know of her genetic and phenotypic status before becoming pregnant so that she is informed as to her options and requirements for safe delivery.

Haemophilia in the first years of life

Surgery in infants and young children with haemophilia, when preceded by accurate diagnosis and accompanied by safe and effective factor prophylaxis, is not associated with a significant risk of haemorrhage. Haemophilic newborns undergoing circumcision or major surgery prior to diagnosis and in the absence of appropriate haemostatic prophylaxis remain as a concern. Inhibitor development has replaced haemorrhage as the major surgical complication in the developed world, largely because of the intensity of treatment used to secure haemostasis. For that reason only, essential surgery should be performed. Intracranial haemorrhage (ICH) during the neonatal period affects 3.5-4.0% of all haemophilia boys in countries with a good standard of health care, which is considerably (40-80 times) higher than expected in the normal population. Because of the high frequency of sporadic cases, ICH in the neonatal period can only be partially prevented by improved carrier diagnosis and counselling. Infections and thrombosis are the major serious complications of central venous lines. Large differences are seen in the frequency of these complications, the most plausible explanations are probably related to the protocol used for device care, the quality of education and the compliance of the users, an issue addressed in an on-going study.

From theory to practice: applying current clinical knowledge and treatment strategies to the care of hemophilia a patients with inhibitors

Two bypassing agents are currently available to circumvent the need for factor FVIII in hemophilia A patients with inhibitors: the activated prothrombin complex FEIBA VH and recombinant activated factor VII (NovoSeven. Both products are highly effective in controlling bleeding in the presence of inhibitory alloantibodies, yet their hemostatic efficacy can be unpredictable. As the results of the FEIBA NovoSeven( Comparative (FENOC) study illustrate, patients may respond better to one bypassing agent than the other. Furthermore, guidelines from an expert panel reflect that responsiveness to bypassing therapy may change from one bleed to the next in the same patient and even from hour to hour during the course of a single bleeding event. These findings underscore the need to have both bypassing products available to treat bleeding episodes in inhibitor patients, to frequently evaluate the efficacy of hemostasis during the course of a bleeding event, and to switch products early if the response to treatment is unsatisfactory.

Neonatal hyperbilirubinemia: an unexpected cause

Hyperbilirubinemia is a common cause for newborn hospital admission. Although the cause of hyperbilirubinemia is usually benign and self-limited, there is always a large differential diagnosis. Atypical presenting signs and symptoms, such as significant anemia or bleeding, should encourage further evaluation for underlying disorders, such as inherited coagulation defects. This article describes the case of a 5-day-old infant who presented to the emergency department with hyperbilirubinemia, anemia, and ecchymoses from birth trauma. His hospital course is described, along with a review on the background, evaluation, management, and complications of hemophilia A.

Haemophilia therapies

In the last few decades dramatic improvements in the management of haemophilia patients have occurred. Haemophilia has moved from a fatal or disabling disease to a hereditary disorder with available treatment and much better clinical outcomes. The safety of antihaemophilic factor concentrates has been dramatically improved and, in a multidisciplinary environment including haematologists, orthopaedic surgeons, paediatrics, infectiologists, specialised nurses and physiotherapists, complications related to haemophilia are now limited, markedly improving the quality of life of haemophiliacs. One can even think that the cure of haemophilia through gene therapy might occur in the next decades. Keeping this ultimate aim in mind, efforts at present are mainly focused on bioengineered Factor VIII/Factor IX concentrates with increased efficacy or longer half-life or decreased immunogenicity. In addition, several preclinical and clinical studies are being carried out for optimising and individually tailoring the therapeutic regimens of antihaemophilic therapies using global haemostasis tests in combination with the routine coagulation assays.