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1.
Haemophilia ; 23(4): 538-546, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28574179

RESUMO

PATIENTS AND METHODS: A longitudinal study was carried out in 255 children from 10 centres in nine developing countries over 5 years to assess the musculoskeletal outcome of children on episodic factor replacement. Outcome was documented by assessment of the annual joint bleeding rate (AJBR), WFH clinical and Pettersson radiological joint scores as well as the FISH score for activities. Of the 203 patients for whom data was available at the end of 5 years, 164 who had received only episodic treatment are included in this report. RESULTS: The median age at the beginning of the study was 10 years (IQR 7-12). The median clotting factor concentrate (CFC) usage was 662 IU kg-1 year-1 (IQ range: 280-1437). The median AJBR was 10 (IQ range: 5-17). The median AJBR was higher in the older children with the median being 5 for the 5 year old child, while it was 9 for the 10 year old and 11 for children older than 15. Given the episodic nature of the replacement therapy, those with a higher AJBR used significantly greater annual CFC doses (P < 0.001); The median change in WFH clinical score and Pettersson radiological score over the 5 years was 0.4/year for each, while the FISH deteriorated at a rate of 0.2/year with poor correlation of these changes with CFC dose. WFH and FISH scores were significantly worse in those with an AJBR of >3 per year (P = 0.001). The change in the Pettersson score was significantly more in those with an AJBR of >5 per year (P = 0.020). Significant changes in FISH scores were only noted after 10 years of age. CONCLUSION: Episodic CFC replacement over a large range of doses does not alter the natural course of bleeding in haemophilia or the musculoskeletal deterioration and should not be recommended as a long term option for treatment. Prophylaxis is the only way to preserve musculoskeletal function in haemophilia.


Assuntos
Fatores de Coagulação Sanguínea/farmacologia , Hemorragia/prevenção & controle , Sistema Musculoesquelético/efeitos dos fármacos , Adolescente , Criança , Feminino , Humanos , Estudos Longitudinais , Masculino , Sistema Musculoesquelético/patologia , Adulto Jovem
2.
BMC Hematol ; 17: 22, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29299315

RESUMO

BACKGROUND: Abnormal fibrinogens can be caused by clinically silent hereditary mutations. A new case was detected accidentally in an 11-year-old girl when routine pre-operative coagulation tests were performed for nasal turbinate surgery. METHODS: The fibrinogen genes FGA, FGG and FGB were sequenced using standard protocols. The kinetics of fibrin formation were followed by turbidity at 350 nm. Purified fibrinogen was incubated with plasmin, and the degradation products analyzed by SDS/PAGE. The formation of fibrinogen-albumin complexes was analyzed by immunobloting. Fibrin structure was examined in a Nikon Eclipse TE 2000-U laser microscope. Secretion of the variant protein was analyzed directly by reverse phase-electrospray time of flight-mass spectrometry (TOF-MS). RESULTS: DNA sequencing revealed a novel heterozygous g. 3057 C > T mutation in the FGA that predicts a p. Arg104 > Cys substitution, in the proband and her father. Both patients were asymptomatic with low functional and antigen fibrinogen concentrations. The proband's plasma fibrinogen polymerization was almost normal, with a 12% decrease in the final turbidity, while, the father's fibrin formation had a diminished slope and final turbidity (2.5× and 40%, respectively). Aα Arg104 is located at a plasmin cleavage site in the coiled-coil region of fibrinogen. However, the father's fibrinogen plasmin degradation was normal. Although the exchanged Cys introduces an unpaired -SH, immunoblotting showed no fibrinogen-albumin complexes. Furthermore, the plasma clot structure observed by confocal microscopy appeared almost normal. TOF-MS showed that the variant Aα chain was underrepresented in plasma and made up only about 25% of the total. CONCLUSIONS: The low expression of the Aα Arg104 > Cys chain in circulation could account for the observed hypodysfibrinogenemia.

3.
Haemophilia ; 21(1): e12-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25359594

RESUMO

Swimming is beneficial for persons with haemophilia (PWH) providing good maintenance of the cardiovascular and musculoskeletal system and improving many psychological characteristics. In the Desafío del Caribe Project, young PWH from Venezuela and Mexico took part in an open water competition in the Gulf of Mexico under a multidisciplinary team supervision. Eight severe haemophilia A, two moderate haemophilia A, one severe haemophilia B and two moderate haemophilia B subjects were included. Haematological, musculoskeletal and psychological evaluations were carried out before and during training for the competition. Training program included physical exercise routines and swimming practices that alternated between pools and open water. Swimmers had coverage with factor concentrates before pool and open water trainings. In physiatric evaluations, the Hemophilia Joint Health Score (HJHS) was used. The objective of the psychology area was to analyse self-esteem, precompetition anxiety, coping mechanisms and relaxation levels. The need of factor prophylaxis before intense trainings was confirmed. In the musculoskeletal system a decrease of elbow pain as well as an increase of muscle strength in the ankles were observed. In the psychological area significant differences between the first and second test in self-esteem levels, cognitive anxiety and group cohesion were found. PWH must be provided with orientation and encouragement to practice swimming regularly. High competition exercise must be supervised by a multidisciplinary team which must evaluate the pros and cons of the activity to make relevant recommendations.


Assuntos
Hemofilia A/fisiopatologia , Hemofilia A/psicologia , Hemofilia B/fisiopatologia , Hemofilia B/psicologia , Natação , Adolescente , Testes Hematológicos , Hemofilia A/sangue , Hemofilia B/sangue , Humanos , Exame Físico , Autoimagem , Adulto Jovem
4.
Haemophilia ; 20(1): e63-70, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24354487

RESUMO

There is a paucity of literature on haemophilia treatment in Latin American countries, a region characterized by rapidly improving systems of care, but with substantial disparities in treatment between countries. The aim of this study was to evaluate the musculoskeletal status of haemophilia patients from Latin America and to examine the relationship between musculoskeletal status and treatment practices across countries. The Committee of Latin America on the Therapeutics of Inhibitor Groups conducted a survey of its member country representatives on key aspects of haemophilia treatment in 10 countries. Musculoskeletal status of patients was obtained during routine comprehensive evaluations between March 2009 and March 2011. Eligible patients had severe haemophilia A (factor VIII <1%) without inhibitors (<0.6 BU mL(-1) ) and were ≥5 years of age. Musculoskeletal status was compared between three groups of countries, based primarily on differences in the availability of long-term prophylaxis. Overall, 143 patients (5-66 years of age) were enrolled from nine countries. In countries where long-term prophylaxis had been available for at least 10 years (Group A), patients aged 5-10 years had significantly better mean World Federation of Hemophilia clinical scores, fewer target joints and fewer affected joints than patients from countries where long-term prophylaxis has been available for about 5 years (Group B) or was not available (Group C). In Latin America, the musculoskeletal status of patients with severe haemophilia without inhibitors has improved significantly in association with the provision of long-term prophylaxis. As more countries in Latin America institute this practice, further improvements are anticipated.


Assuntos
Hemartrose/diagnóstico , Hemartrose/etiologia , Hemofilia A/complicações , Adolescente , Adulto , Fatores Etários , Idoso , Criança , Pré-Escolar , Fator VIII/administração & dosagem , Fator VIII/uso terapêutico , Hemartrose/terapia , Hemofilia A/tratamento farmacológico , Humanos , América Latina , Masculino , Pessoa de Meia-Idade , Pré-Medicação , Índice de Gravidade de Doença , Adulto Jovem
5.
Haemophilia ; 17(5): e913-8, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21371196

RESUMO

Haemophilia A is caused by mutations in the gene encoding coagulation factor VIII (FVIII). In severe Haemophilia A (sHA), two inversions are responsible for approximately 50% of the genetic alterations (intron 22 and intron 1 inversions). The other mutations are extremely diverse and each affected family generally has its own mutation. Our aim was to detect the genetic alterations present in the FVIII gene (F8) in 54 unrelated male patients with sHA in Venezuela. We initially detected the presence of the intron 22 inversion by performing inverse PCR, and the negative patients for this inversion were analysed for the intron 1 inversion by PCR. Patients negative for both inversions were analysed using Conformation Sensitive Gel Electrophoresis for mutations in all exons, promoter region and 3'-UTR. sHA causative mutations were identified in 49 patients. Intron-22 and -1 inversions were detected in 41% and 0% of patients respectively. Besides these two mutations, 25 different mutations were identified, including nine nonsense, four small deletions, two small insertions, four missense, three splicing mutations and three large deletions. Seven novel mutations were identified, including two nonsense mutations, two small deletions, one small insertion, one missense mutation and one splicing mutation. Thirty one percent of the patients with identified mutations developed inhibitors against exogenous FVIII. This is the first report of F8 mutations in patients with sHA in Venezuela; the data from this study suggests that the spectrum of gene defects found in these patients is as heterogeneous as reported previously for other populations.


Assuntos
Fator VIII/genética , Hemofilia A/genética , Mutação/genética , Análise Mutacional de DNA/métodos , Predisposição Genética para Doença , Humanos , Íntrons/genética , Masculino , Venezuela
6.
Haemophilia ; 17(3): 422-7, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21118333

RESUMO

Elective surgery in patients with congenital haemophilia with inhibitors carries a high risk of bleeding. However, inhibitor patients also have a high risk of haemarthroses and other orthopaedic complications, and surgery could improve their quality of life. Successful elective surgery has been reported in inhibitor patients under haemostatic cover with plasma-derived activated prothrombin complex concentrate (pd-aPCC) or recombinant activated factor VII (rFVIIa). Recombinant FVIIa has recently become available in Venezuela and, unlike pd-aPCC, has not been associated with an anamnestic response. The aim of this study was to assess our experience using rFVIIa as a first-line and sustained treatment in elective invasive surgical procedures at the National Haemophilia Centre in Venezuela. Surgical procedures were classified as major or minor, under haemostatic cover with rFVIIa. A total of 13 patients (12 with haemophilia A with high-responding inhibitors and one with von Willebrand's disease type 3) underwent a total of 19 surgical procedures under rFVIIa cover. Thirteen procedures were classified as major surgeries. Intraoperative haemostasis was achieved in the majority of patients. Only two patients required an additional dose of rFVIIa, at 30 min and 75 min, respectively, with good results. Postoperative haemostasis was considered effective in 16 of 18 (89%) of the procedures in haemophilia A patients. Treatment was considered to be ineffective in two patients because of excessive postoperative bleeding. Data from the study provide no safety concerns, and demonstrate that rFVIIa provides effective haemostatic cover in elective surgery in patients with inhibitors; research is ongoing to determine the optimal dose for such procedures.


Assuntos
Perda Sanguínea Cirúrgica/prevenção & controle , Fator VIIa/uso terapêutico , Hemofilia A/tratamento farmacológico , Hemofilia A/cirurgia , Hemostasia Cirúrgica/métodos , Hemostáticos/uso terapêutico , Doença de von Willebrand Tipo 3/tratamento farmacológico , Doença de von Willebrand Tipo 3/cirurgia , Adolescente , Adulto , Inibidores dos Fatores de Coagulação Sanguínea/sangue , Criança , Pré-Escolar , Procedimentos Cirúrgicos Eletivos , Feminino , Hemofilia A/imunologia , Humanos , Masculino , Proteínas Recombinantes/uso terapêutico , Adulto Jovem , Doença de von Willebrand Tipo 3/imunologia
8.
Haemophilia ; 15(1): 267-80, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18976247

RESUMO

The congenital FVII deficiency (FVIID) is a rare haemorrhagic disorder with an autosomal recessive pattern of inheritance. Data on phenotype and the genotype from 717 subjects in Central Europe (six countries), Latin America (Costa Rica, Venezuela) and United States, enrolled in the Greifswald Registry of FVII Deficiency were analysed. We detected 131 different mutations in 73 homozygous, 145 compound heterozygous and 499 heterozygous subjects. Regional differences were observed in the mutation pattern and the clinical profile of the evaluated patients. Seventy-one per cent of homozygous and 50% of compound heterozygous subjects were symptomatic. The clinical manifestations of the homozygous subjects were characterized by intracranial haemorrhage (2%), gastrointestinal bleeding (17%), haemarthrosis (13%), epistaxis (58%), gum bleeding (38%), easy bruising (37%), haematoma (15%), haematuria (10%) and menorrhagia (19 of 26 females, 73%). The clinical variability and genotype-phenotype correlation was evaluated in the homozygous subjects. The pattern of bleeding symptoms among compound heterozygous patients was severe and similar to that of the homozygous patients. The large-scale analysis of 499 heterozygous subjects shows that 93 (19%) presented with spontaneous bleeding symptoms such as haemarthrosis (4%), epistaxis (54%), gum bleeding (14%), easy bruising (38%), haematoma (23%), haematuria (5%) and menorrhagia (19 of 45 females; 42%). The severe haemorrhages - intracranial and gastrointestinal - were not reported in heterozygous subjects. The clinical variability and the regional differences in the mutation pattern are discussed regarding care and treatment.


Assuntos
Deficiência do Fator VII/genética , Fator VII/genética , Mutação , Adolescente , Adulto , Sequência de Bases , Criança , Pré-Escolar , Análise Mutacional de DNA , Deficiência do Fator VII/complicações , Feminino , Genótipo , Hemorragia/etiologia , Hemorragia/genética , Heterozigoto , Homozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Fenótipo , Adulto Jovem
9.
Haemophilia ; 14 Suppl 3: 93-103, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18510528

RESUMO

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.


Assuntos
Transtornos Hemorrágicos/diagnóstico , Testes de Função Plaquetária/métodos , Técnicas de Laboratório Clínico/tendências , Saúde Global , Transtornos Hemorrágicos/classificação , Transtornos Hemorrágicos/epidemiologia , Humanos , Guias de Prática Clínica como Assunto
10.
Haemophilia ; 12(5): 479-89, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16919077

RESUMO

Inherited factor X deficiency (FXD) is a rare (1:1,000,000) recessive bleeding disorder. The clinical and laboratory phenotypes of FXD are poorly correlated and few regional studies on the genotype and the clinical manifestations of FXD are known. To understand the association between clinical manifestations and causative genotype, detailed evaluation of bleeding pattern in a high number of patients is needed. This international study analysed the phenotype and genotype of 102 subjects from Central Europe (Germany, Poland and Slovakia) and Latin America (Costa Rica and Venezuela) with causative mutations in the F10 gene, via sequencing. Twenty-eight homozygous, seven compound-heterozygous and 67 heterozygous FXD subjects were characterized. Twenty-nine different causative mutations, including 15 novel mutations, were analysed. Spontaneous bleeding symptoms in 42 symptomatic individuals (26 homozygous, seven compound heterozygous and nine heterozygous) comprised easy bruising (55%), haematoma (43%), epistaxis (36%), haemarthrosis (33%), intracranial haemorrhage (ICH; 21%), and gastrointestinal (GI) haemorrhage (12%). The manifestation of bleeding symptoms in 9 of 67 (13%) symptomatic heterozygous subjects is described. The bleeding patterns of the enrolled patients showed differences that are associated with the types of F10 mutation, and the corresponding genotypes. The homozygous patients were evaluated for genotype-phenotype correlation. The results suggested that ICH seems to be associated with the F10 mutation Gly380Arg, and possibly with the mutations IVS7-1G>A and Tyr163delAT. A tentative association of other mutations to severe symptoms such as haemarthrosis and GI haemorrhage is reported. The severity of FXD, the genotype-phenotype association, and the results of regional studies are discussed.


Assuntos
Deficiência do Fator X/genética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Costa Rica/epidemiologia , Epistaxe/epidemiologia , Epistaxe/genética , Europa (Continente)/epidemiologia , Fator X/genética , Deficiência do Fator X/congênito , Deficiência do Fator X/epidemiologia , Feminino , Hemartrose/epidemiologia , Hemartrose/genética , Hematoma/epidemiologia , Hematoma/genética , Hemorragia/epidemiologia , Hemorragia/genética , Heterozigoto , Homozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Fenótipo , Prevalência , Venezuela/epidemiologia
11.
Haemophilia ; 11(6): 583-8, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16236107

RESUMO

Therapeutic options for developing countries have to assure an optimum safety and efficacy and low-cost antihaemophilic concentrates. A single blind randomized crossover study was carried out in 12 previously treated HB patients, comparing the pharmacokinetics (PK), thrombogenicity (TG) and safety of two plasma-derived double-inactivated (solvent/detergent heating at 100 degrees C, 30 min) factor IX (FIX) concentrates, UMAN COMPLEX DI (product A) [plasma-derived prothrombin concentrates (PCC)] and a high purity FIX concentrate AIMAFIX DI (product B, HPFIX). In a non-bleeding state, they received one single intravenous dose 50 IU FIX kg(-1) of PCC or HPFIX, and after a wash-out period of 14 days, the other product. We evaluated acute tolerance and determined PK parameters based on FIX levels measured over a 50 h postinfusion period. We studied fibrinogen, platelets, antithrombin, F1 + 2, TAT, D-dimer, over a 360 min postinfusion period. Ten cases remained in on-demand treatment for 6 months, five with PCC and five with HPFIX. PK and anti-FIX inhibitors were repeated at 3 and 6 months. No inhibitors were detected. PK values (PCC vs. HPFIX): clearence (CL; mL h(-1) kg(-1)) 5.2 +/- 1.4 vs. 6.5 +/- 1.4; the volume of distribution at steady state (mL kg(-1)) 154.9 +/- 54.9 vs. 197.5 +/- 72.5; mean residence time (h) 29.7 +/- 8.1 vs. 30.7 +/- 9.2; T(1/2) (h) 22.3 +/- 7 vs. 23.5 +/- 12.3; incremental recovery (IR; U dL(-1) U(-1) kg(-1)) 0.96 +/- 0.17 vs. 0.76 +/- 0.13. HPFIX showed significant lower IR and higher CL. There were no differences in PK at 3 and 6 months. In TG, significant increments in TAT and F1 + 2 at 30 min and 6 h were found with PCC. Product B PK results agrees with reported results for other HPFIX preparations. Use of PCC product A has to consider its thrombogenic activity.


Assuntos
Fatores de Coagulação Sanguínea/administração & dosagem , Fator IX/administração & dosagem , Hemofilia B/tratamento farmacológico , Adolescente , Adulto , Antitrombina III/análise , Biomarcadores/sangue , Fatores de Coagulação Sanguínea/farmacocinética , Estudos Cross-Over , Fator IX/farmacocinética , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Fibrinogênio/análise , Hemofilia B/sangue , Hemofilia B/fisiopatologia , Hemostasia/fisiologia , Humanos , Injeções Intravenosas , Fragmentos de Peptídeos/análise , Peptídeo Hidrolases/sangue , Contagem de Plaquetas/métodos , Protrombina/análise , Método Simples-Cego
12.
Thromb Haemost ; 88(2): 253-8, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12195697

RESUMO

The adsorption of thrombin to fibrin during clotting defines "Antithrombin I" activity. We confirmed that thrombin generation in afibrinogenemic or in Reptilase defibrinated normal plasma was higher than in normal plasma. Repletion of these fibrinogen-deficient plasmas with fibrinogen 1 (gamma A/gamma A), whose fibrin has two "low affinity" non-substrate thrombin binding sites, resulted in moderately reduced thrombin generation by 29-37%. Repletion with fibrinogen 2 (gamma'/gamma A), which in addition to low affinity thrombin-binding sites in fibrin, has a "high affinity" non-substrate thrombin binding site in the carboxy-terminal region of its gamma' chain, was even more effective and reduced thrombin generation by 57-67%. Adding peptides that compete for thrombin binding to fibrin [S-Hir53-64 (hirugen) or gamma'414-427] caused a transient delay in the onset of otherwise robust thrombin generation, indicating that fibrin formation is necessary for full expression of Antithrombin I activity. Considered together, 1) the increased thrombin generation in afibrinogenemic or fibrinogen-depleted normal plasma that is mitigated by fibrinogen replacement; 2) evidence that prothrombin activation is increased in afibrinogenemia and normalized by fibrinogen replacement; 3) the severe thrombophilia that is associated with defective thrombin-binding in dysfibrinogenemias Naples I and New York I, and 4) the association of afibrinogenemia or hypofibrinogenemia with venous or arterial thromboembolism, indicate that Antithrombin I (fibrin) modulates thromboembolic potential by inhibiting thrombin generation in blood.


Assuntos
Fibrina/biossíntese , Fibrinogênio/fisiologia , Hirudinas/análogos & derivados , Trombina/antagonistas & inibidores , Afibrinogenemia , Antitrombinas/farmacologia , Hirudinas/farmacologia , Humanos , Fragmentos de Peptídeos/farmacologia , Ligação Proteica , Protrombina/metabolismo , Trombina/biossíntese , Trombofilia
13.
Haemophilia ; 8(3): 375-81, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12010437

RESUMO

We report our preliminary experience with the use of hyaluronic acid (Synvisc) in 29 joints from 25 different haemophilic patients (17 knees, six shoulders, four ankles, one elbow and one hip). All the joints were grade III of our classification, characterized by synovial thickening, axial deformities and muscle atrophy (chronic arthropathy). In view of the very satisfactory results obtained with this procedure, we have substituted Synvisc for the previous use of intra-articular long-standing corticosteroids that we had been used for some years. This method is theoretically more physiological and does not destroy the joint cartilage further, as corticosteroids can.


Assuntos
Hemartrose/tratamento farmacológico , Hemofilia A/complicações , Ácido Hialurônico/administração & dosagem , Adolescente , Adulto , Idoso , Avaliação de Medicamentos , Seguimentos , Hemofilia A/tratamento farmacológico , Humanos , Injeções Intra-Articulares , Pessoa de Meia-Idade , Dor/prevenção & controle , Satisfação do Paciente , Amplitude de Movimento Articular , Resultado do Tratamento
14.
Haemophilia ; 6 Suppl 1: 128-32, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10982279

RESUMO

Most of the world's haemophilia population lives in countries with few medical or financial resources. As such, they cannot easily obtain viral-inactivated clotting product. Many patients are treated with cryoprecipitate made from locally supplied blood. The reasoning for using cryoprecipitate, instead of viral-inactivated products, is based on an unspoken belief that because blood banks can provide reasonably safe products by using modern testing procedures, transmission of HIV and other blood-borne viruses is rare. However, the risk of acquiring a blood-borne infection increases with every exposure, and haemophilia patients treated with cryoprecipitate or fresh-frozen plasma are exposed to hundreds or thousands of donors during their lifetime. The risk that a person infected with HIV will donate blood during the 'window period' is directly related to the incidence of HIV in the country where the donation occurs. To demonstrate the extent of this problem, we devised a model for estimating the risk that a person with haemophilia will encounter HIV-contaminated cryoprecipitate based on the years of treatment and the underlying incidence rate of HIV among blood donors. We applied the model to two countries with different incidence rates of HIV: Venezuela and the United States. We found that a person with haemophilia who receives monthly infusions of cryoprecipitate prepared from plasma of 15 donors over a lifetime of treatment (60 years) is at significant risk of being exposed to HIV. In the United States there is a 2% risk of being exposed to HIV-contaminated blood product, and in Venezuela, the percentage of risk is 40%. Given this degree of risk, medical care providers should carefully evaluate the use of cryoprecipitate except in emergencies or when no viral-inactivated products are available.


Assuntos
Fator VIII/uso terapêutico , Fibrinogênio/uso terapêutico , Infecções por HIV/transmissão , Hemofilia A/virologia , Doadores de Sangue , Contaminação de Medicamentos , Fibronectinas/uso terapêutico , Infecções por HIV/epidemiologia , Infecções por HIV/etiologia , Hemofilia A/complicações , Hemofilia A/terapia , Humanos , Incidência , Modelos Teóricos , Fatores de Risco , Reação Transfusional , Estados Unidos/epidemiologia , Venezuela/epidemiologia
15.
Haemophilia ; 5(5): 295-300, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10583509

RESUMO

Most of the world's haemophilia population live in countries with developing or emerging economies. As such, they do not have access to viral inactivated clotting product. Many are treated with cryoprecipitate made from locally supplied blood. The rationale for using cryoprecipitate instead of viral inactivated products is based on an implicit belief that because blood banks can provide reasonably safe products by using modern testing procedures, transmission of HIV and other blood-borne viruses is rare. However, the risk of acquiring a blood-borne infection is cumulative, and haemophilia patients treated with cryoprecipitate or fresh-frozen plasma are exposed to hundreds or thousands of donors during their lifetime. The risk that an HIV-infected person will be a donor during the 'window period' is directly related to the incidence of HIV in the country where the donation occurs. To illustrate the extent of this problem, we devise a model for estimating the risk that a person with haemophilia will encounter HIV-contaminated cryoprecipitate as a function of years of treatment and the underlying incidence rate of HIV among blood donors. We apply the model to two countries with different incidence rates of HIV, Venezuela and the USA. Over a lifetime of treatment (60 years), the cumulative risk of HIV exposure for a person with haemophilia receiving monthly infusion of cryoprecipitate prepared from plasma of 15 donors is significant, 2% in the USA and 40% in Venezuela. Considering the cumulative risk for transmitting HIV to patients with haemophilia through cryoprecipitate treatment, medical care providers should carefully evaluate the use of cryoprecipitate in any but emergency conditions or when no virally inactivated products are available.


Assuntos
Hemofilia A/terapia , Preservação de Sangue , Crioglobulinas/efeitos adversos , Criopreservação , Infecções por HIV/sangue , Infecções por HIV/transmissão , Humanos , Fatores de Risco , Reação Transfusional
16.
Br J Haematol ; 105(3): 670-2, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10354129

RESUMO

Two members of a family from Carora, Venezuela, were found to have prothrombin activity levels at 4% of normal and undetectable antigen levels. All exons of the prothrombin gene from the proband were sequenced and a mutation at nucleotide 1305 was identified that would result in the substitution of Cys for Tyr at residue 44. Residue 44 is present in the aromatic stack region of the protein. Substitution of a Cys in this region would result in an abnormal folding of the protein which could be the cause for the observed lack of secretion of the abnormal prothrombin.


Assuntos
Substituição de Aminoácidos/genética , Hipoprotrombinemias/genética , Protrombina/genética , Adolescente , Adulto , Consanguinidade , Feminino , Humanos , Masculino , Mutação/genética , Linhagem , Venezuela
17.
Blood ; 93(7): 2261-6, 1999 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10090935

RESUMO

Combined factors V and VIII deficiency is an autosomal recessive bleeding disorder associated with plasma levels of coagulation factors V and VIII approximately 5% to 30% of normal. The disease gene was recently identified as the endoplasmic reticulum-Golgi intermediate compartment protein ERGIC-53 by positional cloning, with the detection of two founder mutations in 10 Jewish families. To identify mutations in additional families, the structure of the ERGIC-53 gene was determined by genomic polymerase chain reaction (PCR) and sequence analysis of bacterial artificial chromosome clones containing the ERGIC-53 gene. Nineteen additional families were analyzed by direct sequence analysis of the entire coding region and the intron/exon junctions. Seven novel mutations were identified in 10 families, with one additional family found to harbor one of the two previously described mutations. All of the identified mutations would be predicted to result in complete absence of functional ERGIC-53 protein. In 8 of 19 families, no mutation was identified. Genotyping data indicate that at least two of these families are not linked to the ERGIC-53 locus. Taken together, these results suggest that a significant subset of combined factors V and VIII deficiency is due to mutation in one or more additional genes.


Assuntos
Deficiência do Fator V/genética , Genes , Hemofilia A/genética , Lectinas de Ligação a Manose , Proteínas de Membrana/genética , Mutação , Substituição de Aminoácidos , Cromossomos Bacterianos , Clonagem Molecular , Análise Mutacional de DNA , Éxons/genética , Deficiência do Fator V/complicações , Deficiência do Fator V/etnologia , Feminino , Genes Recessivos , Heterogeneidade Genética , Ligação Genética , Genótipo , Haplótipos , Hemofilia A/complicações , Hemofilia A/etnologia , Humanos , Íntrons/genética , Judeus/genética , Masculino , Proteínas de Membrana/deficiência , Linhagem , Mutação Puntual , Reação em Cadeia da Polimerase , Deleção de Sequência
18.
Thromb Res ; 78(2): 95-106, 1995 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-7482436

RESUMO

A congenitally abnormal fibrinogen was isolated from the blood of a young woman with a severe bleeding diathesis. Coagulation tests showed a prolonged Thrombin and Reptilase time partially corrected by Ca2+. Polymerization of thrombin induced preformed fibrin monomers was severely impaired. Thrombin caused the release of fibrinopeptides with normal retention times on HPLC. However, the rate of release was abnormally slow and the total amount of fibrinopeptide A (FpA) released reached only approximately 50% of the theoretical maximum. The rate and quantity of FpA release was normal when Reptilase was used. Transmission Electron Microscopy (TEM) of Thrombin induced clots showed an altered clot structure characterized by a reduced mean fiber diameter. The mother has a polymerization defect similar to the propositus, her fibrinopeptide release is unaffected however. The father has a minor fibrinopeptide release defect suggesting the presence of two populations of fibrinogen. This study supports the idea that the fibrinogen isolated from the propositus has two defects inherited as separate genetic traits. This fibrinogen has been named Fibrinogen Guarenas I.


Assuntos
Afibrinogenemia/genética , Fibrinogênios Anormais/isolamento & purificação , Transtornos Hemorrágicos/genética , Adolescente , Biopolímeros/metabolismo , Feminino , Fibrina/metabolismo , Fibrina/ultraestrutura , Fibrinogênios Anormais/genética , Fibrinogênios Anormais/metabolismo , Fibrinopeptídeo A/metabolismo , Fibrinopeptídeo B/metabolismo , Humanos , Cinética , Masculino , Metrorragia/genética , Microscopia Eletrônica , Trombina/farmacologia , Tempo de Trombina
19.
Thromb Res ; 44(5): 587-98, 1986 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-3810561

RESUMO

A Western Venezuelan indigenous Yukpa(Irapa) family with moderate bleeding and discrepancy in the prothrombin values by biological and immunological methods is described. The propositus presented biological activity of 2% by the methods in one-stage including Staphylocoagulase and Echis carinatus. Electrophoretic migration of the prothrombin in plasma was normal, while the serum only showed one precipitation arc instead of the three of normal serum. The propositus appeared to be homozygous for the abnormal prothrombin which we have denominated Prothrombin Perijá.


Assuntos
Hipoprotrombinemias/genética , Protrombina/análise , Adolescente , Humanos , Imunoeletroforese Bidimensional , Indígenas Sul-Americanos , Masculino , Tempo de Tromboplastina Parcial , Linhagem , Tempo de Protrombina , Venezuela
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