Topical hemostatic agents in oral surgery: a narrative review

Sufficient hemostasis during oral surgical procedures is crucial for successful outcomes and to reduce healthcare resource utilization. The purpose of this narrative review is to give a rational insight into the management of bleeding in oral and dental practice through modern drugs. A narrative literature review has been performed on the present topic identifying all articles on Pubmed/Medline and Google Scholars. Acceptable hemostasis during oral surgery is also required to improve visibility and provide a dry operational area. Many oral surgeons, in their daily practice, encounter problems in controlling postoperative bleeding and use a topical hemostatic agent to promote platelet activation or aggregation to form a stable clot.

Rehabilitation of patients with thin ridges by conical expanders and immediate cone morse dental implant: a case report

BACKGROUND

Horizontal atrophic ridges need a regenerative procedure for implant positioning and fixed rehabilitation. Cone Morse taper implants are characterized by the intimate fitting of the prosthetic interface with the absence of microgaps and micromovements of the interfaces. The aim of this case report was to evaluate the clinical outcome of Cone Morse implant design in split crest augmentation treatment.

CASE REPORT

A female patient with partial edentulism of atrophic posterior maxilla was treated for split crest procedure and implant-supported rehabilitation. A full-thickness flap was elevated, and horizontal and vertical osteotomic lines were produced with piezoelectric device. A total of 4 Cone Morse Taper implants (Universal III, Implacil de Bortoli, Brasil) were positioned and the site was grafted with bone substitute and covered by a heterologous membrane.

CONCLUSIONS

A complete healing of the surgical site was evident at the follow-up with no evidence of bone resorption. No radiolucency or inflammatory aspects of the treated site were evident in the radiographic control. Simultaneous Cone Morse implants positioning with split crest technique seems to be a promising treatment for posterior maxillary rehabilitation of atrophic edentulous ridges.

Phase 1, single-dose escalating study of marzeptacog alfa (activated), a recombinant factor VIIa variant, in patients with severe hemophilia

Essentials Marzeptacog alfa (activated) [MarzAA] is a novel variant of activated human factor VII. A phase 1 dose escalation trial of MarzAA was conducted in subjects with severe hemophilia. MarzAA was safe and tolerated at intravenous doses up to 30 μg kg-1 Data observed support further trials for hemophilia patients with inhibitors to factors VIII/IX.

SUMMARY

Background Marzeptacog alfa (activated) (MarzAA), a new recombinant activated human factor VII (rFVIIa) variant with four amino acid substitutions, was developed to provide increased procoagulant activity and a longer duration of action in people with hemophilia. Objectives To investigate the safety, tolerability, immunogenicity, pharmacokinetics (PK) and pharmacodynamics (PD) of single ascending intravenous bolus doses of MarzAA in non-bleeding patients with congenital hemophilia A or B with or without inhibitors. Methods This international, phase 1, open-label study (NCT01439971) enrolled males aged 18-64 years with severe hemophilia A or B, with or without FVIII or FIX inhibitors. Subjects were assigned to single-dose MarzAA cohorts (0.5, 4.5, 9, 18 or 30 μg kg-1 ). Blood sampling was performed predose and postdose, and subjects were monitored for 60 days postdose. Safety endpoints included adverse events, vital sign changes, electrocardiograms, laboratory abnormalities, and immunogenicity; secondary endpoints included evaluation of PK and PD. Results Overall, in 25 patients, MarzAA was well tolerated at all dose levels tested, and was not associated with dose-limiting toxicity. No treatment-emergent severe or serious adverse events occurred. MarzAA showed linear dose-response PK across the 4.5-30 μg kg-1 dose range, with a terminal half-life of ⁓ 3.5 h. Dose-dependent shortening of the activated partial thromboplastin time and prothrombin time, and evidence of an increase in peak thrombin as determined with a thrombin generation assay, were observed at all doses. Conclusions MarzAA was tolerated at doses up to 30 μg kg-1 . The safety profile and pharmacological effects observed support further clinical trials for the treatment of hemophilic patients with inhibitors.

Clinical Factors Associated with Progression to AIDS in the Italian Cohort of HIV-Positive Hemophiliacs

This study updates estimates of the cumulative incidence of AIDS among Italian patients with congenital coagulation disorders (mostly hemophiliacs), and elucidates the role of age at seroconversion, type and amount of replacement therapy, and HBV co-infection in progression. Information was collected both retrospectively and prospectively on 767 HIV-1 positive patients enrolled in the on-going national registry of patients with congenital coagulation disorders. The seroconversion date was estimated as the median point of each patient’s seroconversion interval, under a Weibull distribution applied to the overall interval. The independence of factors associated to faster progression was assessed by multivariate analysis. The cumulative incidence of AIDS was estimated using the Kaplan-Meier survival analysis at 17.0% (95% Cl = 14.1-19.9%) over an 8-year period for Italian hemophiliacs. Patients with age greater than or equal to 35 years exhibited the highest cumulative incidence of AIDS over the same time period, 32.5% (95% Cl = 22.2-42.8%). Factor IX recipients (i.e. severe B hemophiliacs) had higher cumulative incidence of AIDS (23.3% vs 14.2%, p = 0.01) than factor VIII recipients (i.e. severe A hemophiliacs), as did severe A hemophiliacs on less-than-20,000 IU/yearly of plasma-derived clotting factor concentrates, as opposed to A hemophiliacs using an average of more than 20,000 IU (18.8% vs 10.9%, p = 0.02). No statistically significant difference in progression was observed between HBsAg-positive vs HBsAg-negative hemophiliacs (10.5% vs 16.4%, p = 0.10). Virological, immunological or both reasons can account for such findings, and should be investigated from the laboratory standpoint.

Markers of Hypercoagulability in Patients with Hemophilia B Given Repeated, Large Doses of Factor IX Concentrates during and after Surgery

Purer factor IX (FIX) concentrates have been produced for the treatment of hemophilia B in the attempt to reduce the risk of thrombotic complications associated with the use of prothrombin complex concentrates. To evaluate ex vivo whether or not FIX concentrates activate the coagulation system in conditions associated with a high risk for thrombosis, we measured markers of hypercoagulability in 10 patients with hemophilia B who underwent surgery, mainly orthopedic procedures, covered by multiple concentrate infusions (40-80 U/kg/day). Postinfusion plasma levels of prothrombin fragment 1+2 and factor X activation peptide did not differ significantly from the presurgical levels, neither before nor after each concentrate dose. Therefore, it appears that prolonged treatment of patients with hemophilia B undergoing high risk surgical procedures with high doses of FIX concentrate does not cause systemic activation of coagulation. This suggests that purified FIX concentrates are preferable to prothrombin complex concentrates for conditions associated with an increased risk of thrombosis.

"In vitro" correction of the severe factor V deficiency-related coagulopathy by a novel plasma-derived factor V concentrate

INTRODUCTION

Severe congenital factor V (FV) deficiency is a rare bleeding disorder characterized by very low/undetectable levels of FV. Fresh frozen plasma is the standard treatment for bleeding manifestations. Recently, a novel plasma-derived FV concentrate has been developed.

AIM

To evaluate the "in vitro" ability of the novel FV concentrate to normalize clotting times and generate normal amount of thrombin in plasma collected from patients with severe FV deficiency.

METHODS

Prothrombin time (PT), activated partial thromboplastin time (aPTT), FV activity and antigen levels and thrombin generation were measured pre- and postspiking of plasma samples of 10 patients with increasing doses of FV concentrate (from 0 to 100 IU/dL).

RESULTS

Prothrombin time and activated partial thromboplastin time ratios as well as all thrombin generation parameters were fully corrected by the addition of FV concentrate at a final concentration of 25 IU/dL. However, the addition of FV at a concentration of 1-3 IU/dL was already sufficient to correct peak height and endogenous thrombin potential (but not lag time and time to peak) after activation with 5 pmol/L tissue factor. FV activity and antigen levels showed a linear response to supplementation with the novel FV concentrate.

CONCLUSION

The novel plasma-derived FV concentrate was effective to correct "in vitro" severe FV deficiency in patients. The optimal FV concentration to fully normalize both global clotting times and thrombin generation parameters using the novel plasma-derived FV concentrate was 25 IU/dL.

Prenatal diagnosis of haemophilia B: the Italian experience

This article describes prenatal diagnosis (PND) of haemophilia B (HB) within the framework of Italian haemophilia centres and genetics laboratories. The study details the experience from six haemophilia genetic centres (three in the North, one in the Centre and two in the South of Italy) and summarizes the different techniques used to perform PND of HB during the last 15 years. To date, the Italian HB database includes 373 characterized unrelated patients and their genetic information has permitted the identification of 274 carriers of childbearing age. This database represents the main instrument for timely and precise PND. Sixty-six prenatal diagnoses were performed on 52 HB carriers whose average age at the time was 34 (ranging from 24 to 44 years). In 44 cases, genetic counselling for carrier status determination was performed before pregnancy, while eight were not studied prior to pregnancy. Foetal samples were obtained by chorionic villus sampling in 52 cases, by amniocentesis in 12 while two were diagnosed by analysis of free foetal DNA obtained from maternal peripheral blood. In 35 (53%) pregnancies the foetus was female. For 31 men (47%), haemophilia status was determined by analysis of previously determined informative markers or familial mutations (12 affected and 19 unaffected). There may be more than one laboratory involved in the PND diagnostic pathway (providing DNA extraction, karyotype analysis, gender determination, maternal contamination detection, molecular diagnosis and sequencing). Good communication between all the parties, coordinated by the haemophilia centre, is essential for a successful and rapid process.

Inhibitors in haemophilia B: the Italian experience

The prevalence of inhibitors in haemophilia B is significantly lower than that of patients with haemophilia A. However, the peculiar occurrence of allergic reactions associated with the onset of inhibitor in haemophilia B (HB) may render immune tolerance a risky procedure. We have carried out a detailed survey among all the Italian Hemophilia Centers to analyse all the patients with HB and inhibitors. A total of eight patients were reported among 282 living patients (2.8%) with severe factor IX (FIX) deficiency (FIX < 1 U dL(-1)). In addition, two deceased patients were also identified. Six patients carried nonsense mutations while in four partial or complete gene deletions were detected. Three patients (one deceased) had history of allergic/anaphylactic reaction upon substitutive treatment, which in one case was recurrent and resolved after switching to plasma derived FIX. Immune tolerance was adopted in five patients and in four complete response was achieved while in the remaining it was partial. No nephrotic syndrome was observed. Our data confirm that inhibitors in HB occur in patients with null mutations or complete/partial gene deletion. Immune tolerance can be achieved also in HB patients, without allergic reactions or nephrotic syndrome upon replacement therapy.

Homozygous F5 deep-intronic splicing mutation resulting in severe factor V deficiency and undetectable thrombin generation in platelet-rich plasma

BACKGROUND

Coagulation factor (F) V deficiency is associated with a bleeding tendency of variable severity, but phenotype determinants are largely unknown. Recently, we have shown that three patients with undetectable plasma FV and mild bleeding symptoms had sufficient residual platelet FV to support thrombin generation in platelet-rich plasma (PRP). Therefore, we hypothesized that FV-deficient patients with severe bleeding manifestations may lack platelet FV.

OBJECTIVES

To characterize a FV-deficient patient with a severe bleeding diathesis.

PATIENTS/METHODS

We performed FV mutation screening and functional studies in a 31-year-old male (FV:C < 1%) with umbilical bleeding at birth, recurrent hemarthrosis and muscle hematomas, and a recent intracranial hemorrhage.

RESULTS

The proband was homozygous for a deep-intronic mutation (F5 IVS8 +268A→G) causing the inclusion of a pseudo-exon with an in-frame stop codon in the mature F5 mRNA. Although platelet FV antigen was detectable by immunoprecipitation followed by Western blotting, no FV activity could be demonstrated in the proband's plasma or platelets with a prothrombinase-based assay. Moreover, no thrombin generation was observed in PRP triggered with 1-50 pm tissue factor (even in the presence of platelet agonists), whereas an acquired FV inhibitor was excluded. Clot formation in the proband's whole blood, as assessed by thromboelastometry, was markedly delayed but not abolished.

CONCLUSIONS

This is the first report of a pathogenic deep-intronic mutation in the F5 gene. Our findings indicate that the minimal FV requirement for viability is extremely low and suggest that thrombin generation in PRP may predict bleeding tendency in patients with undetectable plasma FV.

Mortality and causes of death in Italian persons with haemophilia, 1990-2007

Although a number of studies have analysed so far the causes of death and the life expectancy in haemophilic populations, no investigations have been conducted among Italian haemophilia centres. Thus, the aim of this study was to investigate mortality, causes of deaths, life expectancy and co-morbidities in Italian persons with haemophilia (PWH). Data pertaining to a total of 443 PWH who died between 1980 and 2007 were retrospectively collected in the 30 centres who are members of the Italian Association of Haemophilia Centres that chose to participate. The mortality rate ratio standardized to the male Italian population (SMR) was reduced during the periods 1990-1999 and 2000-2007 such that during the latter, death rate overlapped that of the general population (SMR 1990-1999: 1.98 95% CI 1.54-2.51; SMR 2000-2007: 1.08 95% CI 0.83-1.40). Similarly, life expectancy in the whole haemophilic population increased in the same period (71.2 years in 2000-2007 vs. 64.0 in 1990-1999), approaching that of the general male population. While human immunodeficiency virus infection was the main cause of death (45%), 13% of deaths were caused by hepatitis C-associated complications. The results of this retrospective study show that in Italian PWH improvements in the quality of treatment and global medical care provided by specialized haemophilia centres resulted in a significantly increased life expectancy.

Polymorphisms in genes involved in autoimmune disease and the risk of FVIII inhibitor development in Italian patients with haemophilia A

One of the most severe and important complication in the treatment of patients with haemophilia A is the formation of neutralizing antibodies (FVIII inhibitors) that inhibit the clotting activity of substituted FVIII. Both genetic and environmental factors influence the susceptibility of patients to develop inhibitors. The objective of this study was to evaluate whether polymorphisms in different genes involved in the regulation of the immune system may confer susceptibility to inhibitor development in patients with HA. We analysed the distribution of polymorphisms in the CTLA4, PTPN22, IL10, TNFalpha, FOXP3 and IRF5 genes that have been reported to be associated with a number of autoimmune disease. In addition, we evaluated the distribution of IL10 haplotypes in haemophilic patients and healthy controls to assess whether specific polymorphisms in IL10 gene were associated to the risk of inhibitor development. We focused on a cohort of Italian unrelated haemophilic patients with and without a history of inhibitors. Genotyping was carried out with standard methods including RFLP, real time PCR and direct DNA sequencing. Our data show that, considering single nucleotide variations, genotype frequencies in patients with inhibitors were not significantly different from those observed in patients without inhibitors, suggesting a lack of association between these polymorphisms and the development of inhibitors. Moreover, no relationship was found between specific combinations of IL10 alleles and the antibody production. Previous contradictory association studies may depend on the different genetic background of the population examined. Further studies may contribute to a clearer understanding of this process.

F8 gene mutation profile and ITT response in a cohort of Italian haemophilia A patients with inhibitors

Anti factor VIII (FVIII) antibodies represent the main complication of replacement therapy in severe cases of haemophilia and most patients with inhibitor have gross gene rearrangements or point mutations that hamper the production of normal circulating FVIII. In this study we have investigated 82 haemophilia A patients with inhibitors. Seventy six were severe, three were moderate and three were mild. We screened the patients for the causative mutations using long range PCR for the recurrent intron 22 inversion (invint22), multiplex PCR for intron 1 inversion (invint1) and conformation sensitive gel electrophoresis followed by DNA sequencing for all other mutation types in the F8 gene. Diverse genetic defects were detected in the severe cases (with a predominance of severe molecular defects): F8 gene inversions, large deletions and non-sense mutations account for 71% of the mutations. Only missense and splicing mutations were identified in the non-severe patients and we confirmed that the presence of inhibitors correlates well with the presence of severe mutations, but a proportion of severe patients develops inhibitors despite the presence of diverse less severe mutations. When we have analysed the subgroup of patients who underwent immunetolerance, we have found that F8 gene large deletions are likely to be a high risk factor also for immunetolerance therapy unresponsiveness, while no clear evidence has been demonstrated for other mutation types.

European Study on Orthopaedic Status of haemophilia patients with inhibitors

Development of inhibitors against factor VIII (FVIII) or factor IX (FIX) in haemophilia patients is one of the most serious complications of repeated exposure to replacement therapy and has major clinical and economic consequences. To evaluate the relationship between inhibitor status of haemophilia patients and their quality of life (QoL) and degree of arthropathy and to compare the orthopaedic status of patients with/without inhibitors. An observational, cross-sectional, case control study enrolling: group A (n = 38), males aged 14-35 years, with severe congenital haemophilia A or B who had inhibitors against FVIII/FIX >5 years; group B (n = 41), as group A, but aged 36-65 years and group C (n = 49), as group A, but without inhibitors. Socio-demographics: medical history, clinical characteristics and QoL were assessed. In groups A and B, 16% and 27% were hospitalized for orthopaedic procedures vs. 4% in group C. Patient mobility was also severely reduced in groups A and B, with 24% and 22% using wheelchairs vs. 4% in group C, and 50% and 51% needing a walking aid vs. 29% in group C. Significantly more joint pain was reported by patients in group A vs. those in group C; clinical/radiological orthopaedic scores were also worse in group A vs. group C. Significantly more joint abnormality was reported by patients in group A vs. group C. The burden of orthopaedic complications and the impact on QoL are more severe in haemophilia patients who have developed inhibitors than in those without inhibitors.

Tyr2105Cys mutation in exon 22 of FVIII gene is a risk factor for the development of inhibitors in patients with mild/moderate haemophilia A

We report the case of a patient with mild haemophilia A, due to a Tyr2105Cys mutation in exon 22 of the C1 domain, who developed a high-titre factor VIII inhibitor (maximum titre 1600 BU) with recurrent severe haemorrhages and fatal intracranial bleeding. Based on published data, it appears that although this mutation occurs rarely in patients with mild or moderate haemophilia A, it is frequently associated with the development of high-titre inhibitors.

Occurrence of inhibitors in previously untreated or minimally treated patients with haemophilia A after exposure to a plasma-derived solvent-detergent factor VIII concentrate

A solvent-detergent virus-inactivated plasma-derived FVIII concentrate (SD-pdFVIII) has been employed for treatment of Italian patients with haemophilia A for 15 years. This product is a non-monoclonally purified, high purity FVIII concentrate, containing large amounts of von Willebrand factor (VWF). A retrospective survey was carried out in Italy in order to evaluate the immunogenicity of SD-pdFVIII in previously untreated patients (PUPs) or in minimally treated patients (MTPs), i.e. previously exposed for up to 5 days only to other plasma-derived concentrates. The survey included 99 patients with ages ranging from 6 to 64 years (median=21.3) of whom 31 PUPs and 68 MTPs, the latter with a median of four exposure days (EDs; range 1-5) to other plasma products. Surveyed patients had been exposed to SD-pdFVIII for a median of 83 EDs (range 21-1580). Seven patients (three PUPs and four MTPs), all with severe haemophilia, had developed inhibitors [7.1%, 95%; confidence interval: 3-14%] after a median of 11 EDs (range 4-22). Of them, two were low responders (<or=5 BU mL-1) and five high responders. Two low responders and one high responder tolerated inhibitors spontaneously; one high responder underwent immunotolerance treatment with complete, long-standing response. These findings show that SD-pdFVIII is at low risk of inhibitor development in PUPs and MTPs with severe and moderate haemophilia, the risk of inhibitor development being similar to that previously reported for other plasma-derived VWF-containing FVIII products.

Cases of surgery in high-responder haemophilia patients

We present 11 cases of surgery in haemophilia patients with inhibitors (high responders). They were: one haemorroidectomy, one vesical surgery in a high responder, one adenoidectomy, seven orthopaedic procedures (one bone fixation of a femoral neck fracture, four total knee arthroplasties, two total knee arthroplasties), and one retroperitoneal haematoma that required emergency surgery. We conclude that surgery in haemophilia patients with inhibitor can be considered feasible but nevertheless remains difficult. When applied to high-responding patients the treatment must take into account both the haemorrhagic risk and the risk of anamnestic response. Use of activated fractions as first-line therapy makes it possible (if the titre of the antibody allows it) to resort to conventional replacement therapy with FVIII or FIX concentrates. NovoSeven or FEIBA can be equally used as first-line therapy including therapy for major surgeries. It can be useful to alternate one with the other in case of occurrence of haemorrhagic complications.

Consensus perspectives on surgery in haemophilia patients with inhibitors: summary statement

Summary. Participants in an international workshop on surgery in haemophilia patients with inhibitors developed a consensus summary of the findings and conclusions of the meeting. In the consensus, participants agreed upon revised definitions for minor and major surgery, including an intermediate degree of surgery. An evaluation system of intraoperative and postoperative bleeding was developed. Recommended doses of FEIBA((R)) and rFVIIa (both in bolus injections and in continuous infusion) for surgery were agreed. Participants also agreed on the main blood tests to be performed peri-operatively. They also suggested the need of a prospective evaluation in the future. Finally, the approximate number of surgical procedures and costs performed on haemophilia patients with inhibitors were analysed.

Hepatitis C virus quasispecies in the natural course of HCV-related disease in patients with haemophilia

Patients with haemophilia show high prevalence of hepatitis C infection but low rate of progressive liver disease when they are not co-infected with HIV. The balance between host immune system and hepatitis C virus (HCV) variability seems to play a major role in the evolution of the HCV-related disease. To address this point we have studied, in a group of selected patients with haemophilia, the composition and in some cases the evolution, of the highest variable envelope gene within the hypervariable region 1 (HVR1) of the HCV, which is the region more directly exposed to the host immune response. Five of 12 patients show a very high homogeneity of the HVR1 and four of those had severe progressive liver disease. These results seem to confirm the major role of the immunity in driving the variability of the HCV rather than the high degree of different HCV strains to which haemophiliacs have been in touch with, during their long-term replacement therapy. Our results seem in keeping with other studies on different type of patients, where a low degree of quasispecies variability has been demonstrated in relationship with the progression and the severity of their liver disease.

Concurrent total hip and knee replacements in a patient with haemophilia with inhibitors using recombinant factor VIIa by continuous infusion

The introduction of activated recombinant factor VIIa (rFVIIa) has allowed elective surgery to be safely performed in haemophiliacs with inhibitors. The main problems associated with its use are the short half-life, necessitating frequent intravenous injections, and its very high cost. Here we describe, for the first time, the performance of total hip and knee replacements in a haemophiliac with inhibitors at the same operation. The amount of rFVIIa concentrate used (8.57 mg) was similar to that normally used for a single joint replacement. The use of continuous infusion allowed for easier administration and further contributed to the reduction in cost as it avoids the peak levels associated with bolus injections.

Intra-articular rifamycin in haemophilic arthropathy

Synoviorthesis is the intra-articular injection of chemical or radioactive substances able to produce fibrosis of hypertrophied synovium, which has proved effective in the treatment of chronic haemophilic synovitis. Between September 1999 and October 2001 we treated 28 outpatients (25 with haemophilia A, three with haemophilia B). Our treatment was focused on pain and functional limitation of joints. A schedule was adopted to treat each joint using intra-articular rifamycin once a week, repeated five times. Patients were covered with factor replacement on demand. Oral analgesia was offered as required because of acute but transient painful inflammatory reaction. Their median age was 34 years (range 15-60 years). The indication for synoviorthesis was chronic synovitis characterized by recurrent haemarthroses, persistent pain and limited range of motion (ROM). Thirty-five joints were treated with a total of 169 injections, including six joints (20%) in patients with inhibitors. In five patients two joints were treated in the same session. Thirty procedures were completed: 24 (80%) were considered effective (as excellent or good), while six were considered insufficient (20%). Pain was reduced in 96% of cases and in 70% the ROM was improved. In our experience intra-articular infiltration with rifamycin appears to be effective in reducing joint pain and in improving the ROM. The procedure presents a low risk of bleeding, can be used for patients with inhibitors and multiple joints can be treated without any additional cost.

Large FVIII gene deletion confers very high risk of inhibitor development in three related severe haemophiliacs

Haemophilia A displays a broad heterogeneity of genetic defects and of clinical severity. Inhibitor development is the main complication of replacement therapy in severe cases and most patients with inhibitors have gross gene rearrangement or point mutations, which hamper the production of normal circulating factor VIII (FVIII). We have investigated three related severe haemophilia A patients, all of whom have high titre inhibitors. By using long-range polymerase chain reaction (PCR) for FVIII gene inversion, we observed an unusual pattern in these patients. We therefore decided to screen the whole FVIII gene by conformation-sensitive gel electrophoresis. A large FVIII gene deletion spanning exon 2 to exon 25 was identified and we were able to obtain a 18.5 kb PCR product, which is specific for this mutation and useful for determining the carrier state in this family. All three haemophiliacs carrying this very large gene deletion show similar clinical history and very high-titre inhibitors, supporting the observation that inhibitor development seems to be an inherited characteristic. On the basis of our observations we think that this subgroup of patients at very high risk of inhibitor development should be identified by mutation analysis whenever possible, before the beginning of replacement therapy.

Persistence of parvovirus B19 DNA in synovium of patients with haemophilic arthritis

A progressive arthropathy develops commonly in haemophiliacs and its pathogenesis is not fully understood. Human parvovirus B19 has been associated with several diseases including acute and chronic arthropathy and some studies suggest its implication in chronic inflammatory diseases of the joints such as rheumatoid arthritis. In haemophiliacs parvovirus B19 infection occurs very frequently because of its transmission with plasma derivatives. In order to assess a role of B19 virus in haemophilic arthritis, synovial tissue samples from patients with haemophilia with arthritis and from patients, nonhaemophiliacs, with arthrosis or with joint trauma were examined for B19 DNA by nested PCR. In addition, the prevalence of antibody to parvovirus B19 NS1 protein as a possible serological marker of persistent B19 infection was tested and the association of the outcome of parvovirus infection with genetic diversity of B19 P6 promoter sequences was investigated. B19 DNA was detected in the synovial tissue of 31% of haemophiliacs with progressive arthropathy and of 5% of control patients. Fourteen out of 17 patients (82%) with haemophilic arthritis and with B19 DNA in their synovial membranes had IgG antibodies against the nonstructural protein NS1 of parvovirus B19. On the other hand, 19% of patients with haemophilia with B19 PCR negative synovial tissue and 21% of controls showed anti-NS1 antibodies. The P6 promoter presented specific sites of point mutations shared frequently by isolates from patients with haemophilia and arthritis. These results indicate that B19 DNA can persist in the synovial membranes of patients with haemophilic arthritis significantly more frequently in comparison to control individuals with arthrosis or joint trauma and show a correlation between anti- NS1 antibody presence and B19 DNA persistence in the synovial tissue.

Mild bleeding diathesis in a boy with combined severe haemophilia B (C(10400)-->T) and heterozygous factor V Leiden

Haemophilia B patients with factor IX (FIX) activity < 1% are usually characterized by severe bleeding episodes early in life. We report a case of sporadic severe haemophilia B, clinically characterized by mild bleeding diathesis. The presence of anamnestic thrombophlebitis in the patient's mother prompted us to investigate a possible associated hypercoagulable condition. Resistance to activated protein C due to factor V R506Q mutation was present in the mother and in the propositus, in the homozygous and heterozygous form, respectively. Molecular analysis of the FIX gene led to the identification of a nonsense mutation resulting in a stop codon at position 50, previously described and usually responsible for a severe pattern of haemophilia B. The implications of this unusual association are discussed.

Recombinant FVIIa (NovoSeven) continuous infusion and total hip replacement in patients with haemophilia and high titre of inhibitors to FVIII: experience of two cases

In this report we describe our experience of total hip replacement in two patients with severe haemophilia A and high titres of inhibitors to FVIII. We used rFVIIa replacement therapy by continuous infusion to perform the surgery. The total amount of rFVIIa used in these two patients was very similar but the manner of administration was quite different. In our experience, it is an advantage to use a higher dose for shorter periods than a lower dose for a longer treatment period. Tranexamic acid by continuous infusion, and parallel saline infusion were useful for good haemostasis and avoided local thrombophlebitis in the side of rFVIIa infusion.

Experience of a single Italian center in genetic counseling for hemophilia: from linkage analysis to molecular diagnosis

BACKGROUND AND OBJECTIVE

We describe our three year experience in genetic counseling at the Castelfranco Veneto Hemophilia Center, Italy.

DESIGN AND METHODS

A total of 258 individuals were involved in the study of 142 females. These formed 40 families with hemophilia A and 6 families with hemophilia B. Following pedigree analysis, the FVIII inversion was first examined in severe hemophilia A patients by polymerase chain reaction (PCR) analysis. DNA polymorphisms were used to track the affected gene through the remaining families. In uninformative cases, we initiated analysis of the FVIII or FIX gene coding region by conformation sensitive gel electrophoresis and DNA sequencing to identify the mutation responsible for the disease.

RESULTS

The FVIII gene inversion was present in 16 of the 32 patients (50%) affected by severe hemophilia A and was informative for 44 females. For hemophilia A, 45 cases (55%) were informative by linkage analysis, however 37 (45%) were uninformative because of lack of key individuals, homozygosity, or sporadic disease. Information from extragenic linked polymorphisms alone was present in 9 cases (6%). For hemophilia B, linkage analysis was informative in only 50% of females (8 out of 16). To date, nine mutations have been identified in patients with hemophilia A and three in patients with hemophilia B. Six novel missense mutations in hemophilia A are discussed briefly.

INTERPRETATION AND CONCLUSIONS

Using this approach we are now able to offer accurate genetic analysis to virtually all families with hemophilia.

Safety and efficacy of high-purity concentrates in haemophiliac patients undergoing surgery by continuous infusion

In this study we explore the feasibility of high-purity double-inactivated concentrates by continuous infusion for the treatment of haemophiliacs in a group of patients undergoing different surgical procedures. The patients were enrolled in the study on the basis of their transfusion history, which was well known due to their long-term follow up at our Haemophilia Center. We did not perform a pre-operative pharmacokinetic study because one of the aims of this study was to demonstrate that continuous infusion can become a first choice standard treatment in patients with haemophilia. Fourteen haemophilia A and one haemophilia B patients who needed at least 5 days of replacement therapy were monitored for haemostatic efficacy, post-operative factor VIII and factor IX levels and evaluated for safety and flexibility of the products. The infusion rate of 3 IU kg-1 h-1 was demonstrated to be sufficient to ensure haemostasis and patients did not need additional bolus infusion during the post-operative period. Our study demonstrates the safety and feasibility of high-purity concentrates in patients undergoing surgery by continuous infusion, also in the absence of a previous pharmacokinetic study.

Serological markers of autoimmunity in patients with hemophilia A: the role of hepatitis C virus infection, alpha-interferon and factor VIII treatment in skewing the immune system toward autoreactivity

The aim of this study was to investigate whether the immune system of patients with hemophilia A is skewed toward an aspecific activation and to identify the causative factors. It is well known that an immune derangement does exist in patients with hemophilia A. At least three factors potentially play a role: hepatitis C virus (HCV) infection, alpha-interferon therapy and the administration of factor VIII (FVIII). Sixty human immunodeficiency virus (HIV)-negative patients with severe or moderate hemophilia A were studied retrospectively. The serological markers of autoimmunity were evaluated and the results correlated with anti-HCV antibodies, FVIII treatment and alpha-interferon therapy. The role of these factors in the development of the anti-FVIII antibody was estimated concomitantly. The prevalence of autoantibodies and anti-FVIII antibodies was higher in HCV-positive than in HCV-negative patients before any treatment, although the difference was not statistically significant. The administration of FVIII further influenced the development of autoantibodies both in HCV-negative and HCV-positive patients, with no difference being observed between the two groups. As expected, fewer HCV-negative than HCV-positive patients developed anti-FVIII antibodies after administration of FVIII (31.8% versus 38%, respectively). Therapy with alpha-interferon did not seem to enhance significantly the risk of developing autoantibodies nor anti-FVIII antibodies. We observed a high prevalence of humoral signs of autoimmunity among patients with hemophilia A. Treatment with FVIII concentrate is probably the most important triggering factor. Monitoring these patients for autoimmune manifestations is recommended.

Prevalence of anti-FVIII antibodies in severe haemophilia A patients with inversion of intron 22

The aim of our study was to investigate whether haemophilia A patients with inversion of intron 22 are at high risk for non-inhibitory anti-FVIII antibodies development detected by ELISA. It is known that patients with severe forms of haemophilia A are more likely to develop anti-FVIII antibodies. The incidence of inhibitory anti-FVIII antibodies in patients with factor VIII gene inversion has been extensively evaluated, but if this defect has to be considered a predisposing factor is still debatable. Non-inhibitory anti-FVIII antibodies are attracting interest, due to the potential influence on FVIII half-life. Our data show that FVIII gene inversion was a major predisposing factor for anti-FVIII antibodies development.

A multicenter controlled, randomized, open trial of interferon alpha2b treatment of anti-human immunodeficiency virus-negative hemophilic patients with chronic hepatitis C. Hepatitis Study Group of the Association of Italian Hemophilia Centers

There is limited information about the long-term efficacy of prolonged therapy (more than 6 months) with interferon alpha in hemophilic patients with chronic hepatitis C who are not coinfected with the human immunodeficiency virus (HIV-1). One hundred and seven hemophiliacs were randomly assigned to 3 million U of interferon alpha2b three times weekly for 12 months or no therapy. The patients were followed up for at least 12 months posttreatment. Response was assessed by both serial alanine aminotransferase (ALT) levels and hepatitis C virus (HCV)-RNA measured by reverse transcribed polymerase chain reaction (RT-PCR) method. Before treatment, serum levels of HCV-RNA were measured quantitatively by second-generation branched-DNA assay and the HCV genotype was determined by RT-PCR. Serum HGV-RNA, a marker of infection with the hepatitis G virus, was also measured by RT-PCR. Normalization of ALT was sustained and serum HCV-RNA was cleared in 6 of 45 treated patients, compared with none of the 50 untreated controls (13% v 0% P < .01). Low pretreatment viremia was the only feature that was associated with an increased likelihood of sustained response (P < .01). This study shows that multitransfused hemophiliacs with chronic hepatitis C not coinfected with HIV-1 respond at low rates to prolonged interferon therapy.

Predictor of the rate of CD4 lymphocyte loss in HIV-1-seropositive asymptomatic hemophiliacs by in vitro immunoglobulin synthesis

The objective of the present study was to evaluate the prognostic utility in determining the risk of AIDS progression in HIV-1-infected asymptomatic hemophiliacs by in vitro immunoglobulin (Ig) synthesis. With this aim, a cohort of 28 HIV-1-seropositive hemophiliacs were studied. All showed the number of CD4 lymphocytes higher than 400 positive cells/mm3. In all cases the spontaneous and pokeweed mitogen-induced in vitro production of Ig by peripheral blood lymphocytes was evaluated at the beginning of the study and the ratio stimulated/spontaneous (Stim/Spon) synthesis was calculated. At the same time, the absolute CD8+ cell count, IgA serum immunoglobulin, p24 HIV-1 antigenemia, and beta2 microglobulin were calculated. These data were monitored during the 4-year follow-up of patients and compared with the stimulated/spontaneous Ig synthesis ratio to evaluate the predictive significance on the progression of HIV infection. According to the stimulated/spontaneous Ig synthesis ratio, hemophilic patients were separated into two categories. Group I included 12 subjects with a Stim/Spon ratio higher than 2 (the lowest value of normal controls) and group II included 16 cases with a ratio lower than 2. As control, in 36 HIV-1-negative hemophiliac individuals the stimulated/spontaneous Ig ratio ranged between 2 and 42; mean +/- SEM, 12.9 +/- 1.8. At the end of the 4-year follow-up, group I patients showed a CD4 count and clinical staging consistent with those of the first evaluation; in contrast group II demonstrated a significant decrease in CD4 lymphocytes and deterioration of clinical conditions. Our results show that a low Stim/Spon Ig ratio when the CD4 lymphocyte count was still normal appears to predict the depletion of this lymphoid subset and progression to AIDS before T CD8, IgA immunoglobulin, p24 HIV-1 antigenemia, and beta2 microglobulin abnormalities. In this setting, the stimulated/spontaneous Ig ratio may represent a useful tool for clinical decisions in HIV-1-infected hemophiliacs.

A rapid and cost effective method for analysis of dinucleotide repeat polymorphisms in the factor VIII gene

A simple, rapid and cheap method for the analysis of variable dinucleotide tandem polymorphisms in introns 13 and 22 of the factor VIII gene has been established. The protocol uses blood spots stored on filter paper (Guthrie spots) and other DNA containing materials as sources of DNA. Following DNA amplification using a thermostable DNA polymerase, products are size fractionated on native polyacrylamide gels and visualized by silver staining. This simplified protocol obviates the use of DNA extraction, reducing time and costs and in addition, reduces the requirement for gel documentation equipment (i.e., photography), as silver staining can be visualized readily without additional equipment and the gels themselves can be stored. These alterations to the analysis enhance the universal applicability of these polymorphisms, as was demonstrated by a comparative study in Caucasian and Thai females.

Hepatitis C virus genotypes and severity of chronic liver disease in haemophiliacs

We studied the activity and stage of chronic liver disease in 45 HCV-seropositive/HIV-seronegative patients with severe haemophilia followed for at least 10 years. HCV-RNA was detected in serum in 36 patients (80%) Viraemic cases were further analysed for HCV genotypes: 10 (28%) were infected by type 1a, 10 (28%) by type 1b, seven (19%) by type 2, four (11%) by type 3, four (11%) had mixed infections (one by 1a + 1b, one by 1a + 2, one by type 2 + 3, and one by 1a + 2 + 3). ALT levels were within the normal range in 55% of the HCV-RNA negative patients but in only 11% of the viraemic cases. Results show a trend for higher levels of ALT in HCV-RNA-positive patients compared with those without viraemia (98 +/- 56 v 60 +/- 61), and particularly with patients with type 3 HCV infection (148 +/- 44). We suggest that a slow progression of chronic liver disease occurs in haemophilic HCV-positive/HIV-negative patients and conclude that presence of HCV-RNA in serum correlates well with cytolitic damage but, in the time-scale of our follow-up period, commonly used clinical-laboratory parameters cannot predict the chronic evolution of liver infection or identify differences in disease progression in relation to specific HCV subtypes.

Clinical factors associated with progression to AIDS in the Italian cohort of HIV-positive hemophiliacs. G.I.C.C. Gruppo Italiano Coagulopatie Congenite

This study updates estimates of the cumulative incidence of AIDS among Italian patients with congenital coagulation disorders (mostly hemophiliacs), and elucidates the role of age at seroconversion, type and amount of replacement therapy, and HBV co-infection in progression. Information was collected both retrospectively and prospectively on 767 HIV-1 positive patients enrolled in the on-going national registry of patients with congenital coagulation disorders. The seroconversion date was estimated as the median point of each patient's seroconversion interval, under a Weibull distribution applied to the overall interval. The independence of factors associated to faster progression was assessed by multivariate analysis. The cumulative incidence of AIDS was estimated using the Kaplan-Meier survival analysis at 17.0% (95% CI = 14.1-19.9%) over an 8-year period for Italian hemophiliacs. Patients with age greater than or equal to 35 years exhibited the highest cumulative incidence of AIDS over the same time period, 32.5% (95% CI = 22.2-42.8%). Factor IX recipients (i.e. severe B hemophiliacs) had higher cumulative incidence of AIDS (23.3% vs 14.2%, p = 0.01) than factor VIII recipients (i.e. severe A hemophiliacs), as did severe A hemophiliacs on less-than-20,000 IU/yearly of plasma-derived clotting factor concentrates, as opposed to A hemophiliacs using an average of more than 20,000 IU (18.8% vs 10.9%, p = 0.02). No statistically significant difference in progression was observed between HBsAg-positive vs HBsAg-negative hemophiliacs (10.5% vs 16.4%, p = 0.10). Virological, immunological or both reasons can account for such findings, and should be investigated from the laboratory standpoint.

Markers of hypercoagulability in patients with hemophilia B given repeated, large doses of factor IX concentrates during and after surgery

Purer factor IX (FIX) concentrates have been produced for the treatment of hemophilia B in the attempt to reduce the risk of thrombotic complications associated with the use of prothrombin complex concentrates. To evaluate ex vivo whether or not FIX concentrates activate the coagulation system in conditions associated with a high risk for thrombosis, we measured markers of hypercoagulability in 10 patients with hemophilia B who underwent surgery, mainly orthopedic procedures, covered by multiple concentrate infusions (40-80 U/kg/day). Postinfusion plasma levels of prothrombin fragment 1 + 2 and factor X activation peptide did not differ significantly from the presurgical levels, neither before nor after each concentrate dose. Therefore, it appears that prolonged treatment of patients with hemophilia B undergoing high risk surgical procedures with high doses of FIX concentrate does not cause systemic activation of coagulation. This suggests that purified FIX concentrates are preferable to prothrombin complex concentrates for conditions associated with an increased risk of thrombosis.

Antibody to hepatitis C virus and liver disease in volunteer blood donors

OBJECTIVE

To evaluate the specificity of antibodies to hepatitis C virus (anti-HCV) and their relation to liver disease in blood donors.

DESIGN

Case series of consecutive blood donors found positive for anti-HCV by enzyme-linked immunosorbent assay (ELISA). Patients were evaluated for antibody specificity using a recombinant immunoblotting assay (RIBA) and were evaluated for biochemical evidence of liver disease. Patients showing increased alanine aminotransferase (ALT) levels had a liver biopsy.

SETTING

University hospital.

PARTICIPANTS

Fifty consecutive blood donors found to be anti-HCV positive on both an initial and repeat ELISA. Inclusion criteria were as follows: an absence of hepatitis B surface antigens and non-organ-specific autoantibodies; a daily alcohol intake of less than 50 g; no history of recent hepatotoxic drug use; and normal serum levels of alpha 1 antitrypsin, ceruloplasmin, and copper.

MAIN RESULTS

Anti-HCV positivity was confirmed by RIBA in only 13 of 50 donors (26%) who had positive ELISA results. These 13 donors had an elevated ALT level and histologic evidence of chronic hepatitis, which was active in 8 patients (62%) and had already produced cirrhosis in 2 patients (15%). In contrast, the 17 donors with an intermediate RIBA pattern had only mild and often nonspecific histologic liver abnormalities. The 20 patients with a negative RIBA result had normal ALT levels.

CONCLUSION

In blood donors, the anti-HCV RIBA is not only more specific than the anti-HCV ELISA, but is also useful in identifying patients who have an underlying chronic liver disease.

Antibody response to pre-S2 and hepatitis B virus induced liver damage

Antibodies to the pre-S2 encoded sequence of the hepatitis B virus (HBV) envelope were detected in 83% of patients recovering from acute hepatitis B. Such antibodies were absent in cases showing chronic evolution and were found in less than 10% of chronic hepatitis B cases, with no relation to liver disease activity. In acute infection anti-pre-S2 became detectable when maximum liver damage had already occurred and was still detectable in 30% of the cases tested 5-7 years after recovery, as well as in 40% of healthy individuals with naturally acquired immunity to HBV. 10 out of 20 recipients of a plasma-derived, pre-S2-containing, HB vaccine acquired anti-pre-S2 and had no evidence of concurrent liver damage or of autoimmune reactions to human albumin or of suppression of the anti-HBs response. These findings indicate that the antibody response to pre-S2 is a marker of HBV clearance and has no role in the pathogenesis of HBV-related liver damage.

Hepatitis B core antigen in serum during acute hepatitis B

Hepatitis B core antigen was measured in sera of patients with acute and chronic hepatitis B virus infection by a modified radioimmunoassay based on high molarity treatment of samples to avoid masking of antigen by homologous antibody. A good correlation between hepatitis B core antigen levels and serum HBV-DNA was observed in sera obtained during chronic infection. In contrast, acute phase sera were often HBcAg positive but HBV-DNA negative, particularly when obtained during maximum liver damage. Sequential studies in 5 patients with acute hepatitis B showed that HBcAg positivity persisted beside HBV-DNA clearance and was often enhanced at the time of maximum liver damage, suggesting release of antigen from infected hepatocytes undergoing immunolysis, even after termination of virus replication.