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1.
Haemophilia ; 24(1): 85-96, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29044825

RESUMO

INTRODUCTION: Outcome data on treatment of patients with haemophilia A spanning several years of real-world evidence collection are currently very limited. AIM AND METHODS: The global prospective long-term Advate® Haemophilia A Outcome Database (AHEAD) cohort study collects real-world data from patients with severe and moderate haemophilia. We report an interim data read-out after three years of observation. RESULTS: A total of 522 patients were enrolled from 21 countries: 334 completed year 1 follow-up, 238 completed year 2 and 136 completed year 3, with an overall follow-up of 811 patient-years. Median annual bleeding rates (ABR) were 1.7 in the prophylaxis group and 8.9 in the on-demand group at year 1 visit, 1.6 and 13.0, respectively, at year 2 visit and 2.2 and 10.3, respectively, at year 3 visit. Moreover, about 42% of patients on prophylaxis vs 12% of patients on on-demand had zero annual joint bleeding rates (AJBR). Effectiveness of prophylaxis and on-demand treatment was deemed excellent/good in the majority of cases. Octocog alfa (Advate® ) was well tolerated. The inhibitors that developed in nine patients all disappeared spontaneously. Three patients had been previously exposed to FVIII for ≤50 exposure days (EDs), 3 for >50 EDs and 3 showed a borderline positive inhibitory activity (≤0.6 BU/mL). CONCLUSIONS: These data confirm that the goal of zero bleeds is achievable, although not yet achieved in all patients. Understanding reasons behind the lower response to standard prophylaxis regimens in some patients and personalizing prophylactic treatment may further improve outcome in patients with haemophilia A.


Assuntos
Fator VIII/uso terapêutico , Hemofilia A/patologia , Hemorragia/prevenção & controle , Adolescente , Adulto , Idoso , Inibidores dos Fatores de Coagulação Sanguínea/sangue , Criança , Pré-Escolar , Bases de Dados Factuais , Fator VIII/efeitos adversos , Hemofilia A/complicações , Hemofilia A/tratamento farmacológico , Humanos , Lactente , Recém-Nascido , Artropatias/etiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto Jovem
2.
Haemophilia ; 23(4): e335-e339, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28544263

RESUMO

INTRODUCTION: Measuring factor VIII (FVIII) activity can be challenging when it has been modified, such as when FVIII is pegylated to increase its circulating half-life. Use of a product-specific reference standard may help avoid this issue. AIM: Evaluate the impact of using a product-specific reference standard for measuring the FVIII activity of BAX 855 - a pegylated FVIII - in eight of Switzerland's main laboratories. METHODS: Factor VIII-deficient plasma, spiked with five different concentrations of BAX 855, plus a control FVIII sample, was sent to the participating laboratories. They measured FVIII activity by using either with a one-stage (OSA) or the chromogenic assay (CA) against their local or a product-specific reference standard. RESULTS: When using a local reference standard, there was an overestimation of BAX 855 activity compared to the target concentrations, both with the OSA and CA. The use of a product-specific reference standard reduced this effect: mean recovery ranged from 127.7% to 213.5% using the OSA with local reference standards, compared to 110% to 183.8% with a product-specific reference standard, and from 146.3% to 182.4% using the CA with local reference standards compared to 72.7% to 103.7% with a product-specific reference standard. CONCLUSION: In this in vitro study, the type of reference standard had a major impact on the measurement of BAX 855 activity. Evaluation was more accurate and precise when using a product-specific reference standard.


Assuntos
Bioensaio/normas , Fator VIII/química , Fator VIII/metabolismo , Polietilenoglicóis/química , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Padrões de Referência , Suíça
3.
Am J Transplant ; 15(10): 2588-601, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25966640

RESUMO

T cell depletion with antithymocyte globulins (ATG) can be complicated by thrombopenia and hypercoagulability. The underlying mechanism is still unclear. We found that binding of ATG to platelets caused platelet aggregation, α-granule release, membrane phosphatidylserine exposure and the rapid release of procoagulant platelet microvesicles (MV). Platelet activation and MV release were complement-dependent and required membrane insertion of C5b-8 but not stable lytic pore formation by C5b-9. ATG also activated platelets via binding to the low-affinity Fc gamma receptor FcγRII. However, only complement inhibition but not blockade of FcγRII prevented MV release and subsequent thrombin activation in plasma. In 19 hematopoietic stem cell and kidney transplant patients, ATG treatment resulted in thrombopenia and increased plasma levels of d-dimer and thrombin-antithrombin complexes. Flow cytometric analysis of complement fragments on platelet MV in patient plasma confirmed dose-dependent complement activation by ATG. However, the rapid rise in MV numbers observed in vitro was not seen during ATG treatment. In vitro experiments suggested that this was due to adherence of C3b-tagged MV to red blood cells via complement receptor CR1. These data suggest a clinically relevant link between complement activation and thrombin generation and offer a potential mechanism underlying ATG-induced hypercoagulability.


Assuntos
Soro Antilinfocitário/efeitos adversos , Transplante de Células-Tronco Hematopoéticas , Imunossupressores/efeitos adversos , Transplante de Rim , Ativação Plaquetária/efeitos dos fármacos , Trombofilia/induzido quimicamente , Soro Antilinfocitário/uso terapêutico , Biomarcadores/sangue , Micropartículas Derivadas de Células/efeitos dos fármacos , Ativação do Complemento/efeitos dos fármacos , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/prevenção & controle , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/prevenção & controle , Humanos , Imunossupressores/uso terapêutico , Ativação Plaquetária/imunologia , Trombina/metabolismo , Trombocitopenia/sangue , Trombocitopenia/induzido quimicamente , Trombocitopenia/diagnóstico , Trombofilia/sangue , Trombofilia/diagnóstico
4.
Br J Anaesth ; 108(5): 754-62, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22311365

RESUMO

BACKGROUND: Severe aortic stenosis is associated with loss of the largest von Willebrand factor (vWF) multimers, which could affect primary haemostasis. We hypothesized that the altered multimer structure with the loss of the largest multimers increases postoperative bleeding in patients undergoing aortic valve replacement. METHODS: We prospectively included 60 subjects with severe aortic stenosis. Before and after aortic valve replacement, vWF antigen, activity, and multimer structure were determined and platelet function was measured by impedance aggregometry. Blood loss from mediastinal drainage and the use of blood and haemostatic products were evaluated perioperatively. RESULTS: Before operation, the altered multimer structure was present in 48 subjects (80%). Baseline characteristics and laboratory data were similar in all subjects. The median blood loss after 6 h was 250 (105-400) and 145 (85-240) ml in the groups with the altered and normal multimer structures, respectively (P=0.182). After 24 h, the cumulative loss was 495 (270-650) and 375 (310-600) ml in the groups with the altered and normal multimer structures, respectively (P=0.713). Multivariable analysis revealed no significant influence of multimer structure and platelet function on bleeding volumes after 6 and 24 h. After 24 h, there was no obvious difference in vWF antigen, activity, and multimer structure in subjects with and without the altered multimer structure before operation or in subjects with and without perioperative plasma transfusion. CONCLUSIONS: The altered vWF multimer structure before operation was not associated with increased bleeding after aortic valve replacement. Our findings might be explained by perioperative release of vWF and rapid recovery of the largest vWF multimers.


Assuntos
Estenose da Valva Aórtica/cirurgia , Implante de Prótese de Valva Cardíaca/efeitos adversos , Hemorragia Pós-Operatória/sangue , Fator de von Willebrand/metabolismo , Idoso , Idoso de 80 Anos ou mais , Estenose da Valva Aórtica/sangue , Biomarcadores/sangue , Coleta de Amostras Sanguíneas/métodos , Transfusão de Sangue , Feminino , Seguimentos , Humanos , Masculino , Peso Molecular , Agregação Plaquetária/fisiologia , Hemorragia Pós-Operatória/etiologia , Estudos Prospectivos , Multimerização Proteica
5.
Anaesthesist ; 60(5): 451-6, 2011 May.
Artigo em Alemão | MEDLINE | ID: mdl-21184040

RESUMO

Thrombotic microangiopathies are characterized by platelet activation, endothelial damage, hemolysis and microvascular occlusion. This group of diseases is primary represented by thrombotic thrombocytopenic purpura (TTP) and hemolytic uremic syndrome (HUS). Patients present with microangiopathic hemolytic anemia and thrombocytopenia as well as occlusion-related organ ischemia to a variable degree. A deficiency of the metalloprotease ADAMTS-13 is a major risk for acute disease manifestation as this is a regulator of unusually large von Willebrand factor (vWF) multimers, which are extremely adhesive and secreted by endothelial cells. In classical TTP an ADAMTS-13 activity below 5% is specific, whereas in other forms of thrombotic microangiopathies activity of ADAMTS-13 ranges from very low to normal. Symptoms of different forms of thrombotic microangiopathy are frequently overlapping and a clear classification according to clinical criteria is often difficult. Due to a high mortality, particularly of TTP, immediate diagnosis and therapy are essential. In this article two cases of thombotic microangiopathy after cardiac surgery are reported. After exclusion of TTP and HUS as well as other etiologies of thrombotic microangiopathy a relationship between the use of extracorporeal circulation and the pathogenesis of thrombotic microangiopathy is assumed.


Assuntos
Circulação Extracorpórea/efeitos adversos , Doenças Vasculares Periféricas/diagnóstico , Doenças Vasculares Periféricas/etiologia , Trombose/etiologia , Proteínas ADAM/genética , Proteína ADAMTS13 , Idoso de 80 Anos ou mais , Doenças da Aorta/complicações , Doenças da Aorta/cirurgia , Aspirina/uso terapêutico , Coma/etiologia , Cuidados Críticos , Diagnóstico Diferencial , Feminino , Síndrome Hemolítico-Urêmica/etiologia , Síndrome Hemolítico-Urêmica/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/complicações , Insuficiência da Valva Mitral/cirurgia , Doenças Vasculares Periféricas/genética , Inibidores da Agregação Plaquetária/uso terapêutico , Complicações Pós-Operatórias/genética , Complicações Pós-Operatórias/terapia , Púrpura Trombocitopênica/etiologia , Púrpura Trombocitopênica/terapia , Fatores de Risco , Fator de von Willebrand/genética
6.
Internist (Berl) ; 52(1): 89-98, 2011 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-21088954

RESUMO

Anesthesiologists and surgeons are increasingly faced with patients who are under long-term medication. Some of these drugs can interact with anaesthetics or anaesthesia and/or surgical interventions. As a result, patients may experience complications such as bleeding, ischemia, infection or severe circulatory reactions. On the other hand, perioperative discontinuation of medication is often more dangerous. The proportion of outpatient operations has increased dramatically in recent years and will probably continue to increase. Since the implementation of DRGs (pending in Switzerland, introduced in Germany for some time), the patient enters the hospital the day before operation. This means that the referring physician as well as anesthesiologists and surgeons at an early stage must deal with issues of perioperative pharmacotherapy. This review article is about the management of the major drug classes during the perioperative period. In addition to cardiac and centrally acting drugs and drugs that act on hemostasis and the endocrine system, special cases such as immunosuppressants and herbal remedies are mentioned.


Assuntos
Tratamento Farmacológico/métodos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle , Assistência Perioperatória/métodos , Pré-Medicação/efeitos adversos , Pré-Medicação/métodos , Humanos
8.
Hamostaseologie ; 29(2): 161-7, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19404517

RESUMO

Bernard-Soulier syndrome (BSS) is a rare, autosomal recessive inherited bleeding disorder associated with thrombocytopenia, thrombocytopathy and giant platelets. BSS is caused by genetic alterations of the glycoprotein (GP) Ib/V/IX complex. We report on a large Swiss family of whom four family members suffer from BSS. Here, a homozygous missense mutation in position 1829 (A(R)G) of the GPIX gene constituting a N45S substitution is the cause for the bleeding symptoms. A total of 38 family members within two generations were analyzed regarding the N45S mutation by DNA sequencing and restriction fragment length polymorphism. The laboratory parameters which are characteristically for BSS such as platelet count, platelet volume and the expression of CD42a (GPIX), CD42b (GPIbalpha) and CD41 (GPIIb) were measured for all 38 individuals. The four homozygous patients showed bleeding symptoms, thrombocytopenia and giant platelets. In these patients, the expression of CD42a (GPIX), CD42b (GPIbalpha) was diminished. Interestingly, the intensity of the bleeding symptoms of the 4 homozygous family members seemed to vary although they carry the same mutation. The 24 heterozygous carriers did not differ significantly from their 10 wildtype family members regarding bleeding symptoms and laboratory analysis.


Assuntos
Síndrome de Bernard-Soulier/genética , Complexo Glicoproteico GPIb-IX de Plaquetas/genética , Adulto , Portador Sadio , Criança , Feminino , Triagem de Portadores Genéticos , Genótipo , Homozigoto , Humanos , Masculino , Linhagem , Fenótipo , Polimorfismo de Nucleotídeo Único , Suíça
9.
Kidney Int Suppl ; (108): S152-8, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18379539

RESUMO

Hyperphosphatemia is independently associated with an increased risk of death among dialysis patients. In this study, we have assessed the status of phosphate control and its clinical and laboratory associations in a large international group of patients on chronic peritoneal dialysis (PD) treatment. This cross-sectional multicenter study was carried out in 24 centers in three different countries (Canada, Greece, and Turkey) among 530 PD patients (235 women, 295 men) with a mean+/-s.d. age of 55+/-16 years and mean duration of PD of 33+/-25 months. Serum calcium (Ca(2+)), ionized Ca(2+), phosphate, intact parathyroid hormone (iPTH), 25-hydroxy vitamin D(3), 1,25-dihydroxy vitamin D(3), total alkaline phosphatase, and bone alkaline phosphatase concentrations were investigated, along with adequacy parameters such as Kt/V, weekly creatinine clearance, and daily urine output. Mean Kt/V was 2.3+/-0.65, weekly creatinine clearance 78.5+/-76.6 l, and daily urine output 550+/-603 ml day(-1). Fifty-five percent of patients had a urine volume of <400 ml day(-1). Mean serum phosphorus level was 4.9+/-1.3 mg per 100 ml, serum Ca(2+) 9.4+/-1.07 mg per 100 ml, iPTH 267+/-356 pg ml(-1), ionized Ca(2+) 1.08+/-0.32 mg per 100 ml, calcium phosphorus (Ca x P) product 39+/-19 mg(2)dl(-2), 25(OH)D(3) 8.3+/-9.3 ng ml(-1), 1,25(OH)(2)D(3) 9.7+/-6.7 pg ml(-1), total alkaline phosphatase 170+/-178 U l(-1), and bone alkaline phosphatase 71+/-108 U l(-1). While 14% of patients were hypophosphatemic, with a serum phosphorus level lower than 3.5 mg per 100 ml, most patients (307 patients, 58%) had a serum phosphate level between 3.5 and 5.5 mg per 100 ml. Serum phosphorus level was 5.5 mg per 100 ml or greater in 28% (149) of patients. Serum Ca(2+) level was > or =9.5 mg per 100 ml in 250 patients (49%), between 8.5 and 9.5 mg per 100 ml in 214 patients (40%), and lower than 8.5 mg per 100 ml in 66 patients (12%). Ca x P product was >55 mg(2)dl(-2) in 136 patients (26%) and lower than 55 mg(2)dl(-2) in 394 patients (74%). Serum phosphorus levels were positively correlated with serum albumin (P<0.027) and iPTH (P=0.001), and negatively correlated with age (P<0.033). Serum phosphorus was also statistically different (P = 0.013) in the older age group (>65 years) compared to younger patients; mean levels were 5.1+/-1.4 and 4.5+/-1.1 mg per 100 ml, respectively, in the two groups. In our study, among 530 PD patients, accepted uremic-normal limits of serum phosphorus control was achieved in 58%, Ca x P in 73%, serum Ca(2+) in 53%, and iPTH levels in 24% of subjects. Our results show that chronic PD, when combined with dietary measures and use of phosphate binders, is associated with satisfactory serum phosphorus control in the majority of patients.


Assuntos
Falência Renal Crônica/sangue , Falência Renal Crônica/terapia , Diálise Peritoneal/métodos , Fósforo/sangue , Adulto , Idoso , Fosfatase Alcalina/sangue , Transporte Biológico/fisiologia , Cálcio/sangue , Creatinina/sangue , Estudos Transversais , Feminino , Humanos , Hiperfosfatemia/sangue , Hiperfosfatemia/prevenção & controle , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue
10.
J Clin Invest ; 103(2): 229-38, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9916135

RESUMO

beta3 integrins have been implicated in a wide variety of functions, including platelet aggregation and thrombosis (alphaIIbbeta3) and implantation, placentation, angiogenesis, bone remodeling, and tumor progression (alphavbeta3). The human bleeding disorder Glanzmann thrombasthenia (GT) can result from defects in the genes for either the alphaIIb or the beta3 subunit. In order to develop a mouse model of this disease and to further studies of hemostasis, thrombosis, and other suggested roles of beta3 integrins, we have generated a strain of beta3-null mice. The mice are viable and fertile, and show all the cardinal features of GT (defects in platelet aggregation and clot retraction, prolonged bleeding times, and cutaneous and gastrointestinal bleeding). Implantation appears to be unaffected, but placental defects do occur and lead to fetal mortality. Postnatal hemorrhage leads to anemia and reduced survival. These mice will allow analyses of the other suggested functions of beta3 integrins and we report that postnatal neovascularization of the retina appears to be beta3-integrin-independent, contrary to expectations from inhibition experiments.


Assuntos
Antígenos CD/genética , Glicoproteínas da Membrana de Plaquetas/genética , Trombastenia/genética , Animais , Tempo de Sangramento , Sistema Digestório/patologia , Modelos Animais de Doenças , Contagem de Eritrócitos , Feminino , Feto/anormalidades , Feto/fisiopatologia , Imunofluorescência , Marcação de Genes/métodos , Hemorragia/patologia , Integrina beta3 , Integrinas/metabolismo , Contagem de Leucócitos , Camundongos , Camundongos Knockout , Agregação Plaquetária/genética , Útero/patologia
11.
Clin Nephrol ; 68(4): 228-34, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17969490

RESUMO

AIM: The aim of our study was the long-term evolution of hepatitis B immunity and the titers of antibodies against the surface antigen (anti-HBs) acquired either naturally or after vaccination in hemodialysis (HD) patients with no history of hepatitis C virus (HCV) infection. METHODS: 36 HD patients were vaccinated with 4 doses of 40 microg recombinant B vaccine (Engerix, Rixensart, Belgium), intramuscularly at 0, 1, 2 and 6 months. 21 patients (60%) seroconverted developing anti-HBs titers > or = 10 IU/ml. Two patients were transferred to another unit before completion of 6 months after the last vaccine dose. We followed-up 19 HD patients who were immune against HBV after vaccination (Group A), and 30 immune patients (anti-HBs titers > or = 10 IU/ml) who had never been vaccinated and had antibodies against the core antigen (anti-HBc), diagnostic of natural HBV infection (Group B). In all patients of Groups A and B, anti-HBs were determined every 6 months, starting 6 months after the last dose in the vaccinated patients. Follow-up period lasted from October 2002 - April 2006. RESULTS: The mean follow-up in Group A was 21 +/- 12 months (range 6 - 36) and in Group B 29 +/- 12 months (range 6 - 42). Age, sex, presence of diabetes mellitus and duration of dialysis did not differ between the two groups. Five patients in Group A (26%) and 2 patients in Group B (9%) lost immunity (anti-HBs < 10 IU/ml) (p = 0.07). The median time to loss of immunity in Group A patients was 12 months (interquartile range 6 - 18 months), while in Group B patients it was 15 months (interquartile range 12 - 18 months). No booster dose was administered during the study. The 2 patients of Group B who lost immunity were the oldest of the group and redeveloped anti-HBs 6 and 12 months after they had lost it. During the first 6 months of the follow-up period, Group A had significantly higher anti-HBs titers than Group B (p < 0.05). However, this difference was lost later on, and after the first year of follow-up, anti-HBs titers were decreased significantly in Group A (p < 0.05), but remained unchanged in Group B throughout the follow-up period. CONCLUSIONS: In conclusion, HD patients lost hepatitis B immunity both after natural infection or vaccination, but naturally infected patients easily redeveloped protective anti-HBs titers. Anti-HBs titers decreased faster in vaccinated patients than in those with natural acquired immunity who held stable titers for a longer period. It is suggested that HD patients should be followed-up regularly for loss of HBV immunity after vaccination and receive a boosting dose when this occurs. In contrast, patients who acquired natural immunity do not need any anamnestic vaccination.


Assuntos
Anticorpos Anti-Hepatite B/sangue , Hepatite B/imunologia , Imunidade Ativa , Diálise Renal/efeitos adversos , Idoso , Feminino , Vacinas contra Hepatite B/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Tempo , Vacinação/estatística & dados numéricos
12.
Thromb Res ; 157: 142-146, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28753477

RESUMO

INTRODUCTION: Severe blood loss and related haemodilution during cardiac surgery result in a reduced platelet count which may lead to impaired primary haemostasis. Additionally, the reduced haematocrit lowers rheological forces in circulation and may account for lowered platelet adhesiveness and potentially reduced von Willebrand factor (VWF) activity. These mechanisms may lead to postoperative bleeding. Aim of this study was the examination of VWF activity and VWF-mediated platelet adhesion to collagen under conditions of haemodilution. MATERIALS AND METHODS: An in vitro flow chamber was utilized to examine the primary haemostasis under a high arterial shear rate of 1500s-1 at variable VWF concentrations, platelet counts and haematocrit levels. RESULTS: Under a high arterial shear rate, VWF activity is highly dependent on blood viscosity. Both VWF-collagen binding and VWF-mediated platelet adhesion to collagen were significantly increased with increasing haematocrit. Interestingly, we found slight differences in the VWF multimer sizes able to bind collagen under different shear stress conditions. Under conditions of haemodilution, platelet adhesion was strongly dependent on VWF concentration. Increasing VWF concentration improved platelet adhesiveness under low haematocrit conditions (30%) and variable platelet counts (80, 150 and 250×109/L). This effect was nearly abolished at very low platelet count levels of 50×109/L. CONCLUSIONS: VWF improves platelet function under conditions of haemodilution. Therefore, increasing VWF concentration may represent a complementary strategy to administration of platelet concentrates for the management of bleeding in thrombocytopenia.


Assuntos
Hemodiluição/métodos , Hemostasia/efeitos dos fármacos , Fator de von Willebrand/uso terapêutico , Humanos , Fator de von Willebrand/farmacologia
13.
J Thromb Haemost ; 15(8): 1576-1583, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28574652

RESUMO

Essentials Accurate determination of anticoagulant plasma concentration is important in clinical practice. We studied the accuracy and consistency of anti-Xa assays for rivaroxaban in a multicentre study. In a range between 50 and 200 µg L-1 , anti-Xa activity correlated well with plasma concentrations. The clinical value might be limited by overestimation and intra- and inter-individual variation. SUMMARY: Background Determining the plasma level of direct oral anticoagulants reliably is important in the work-up of complex clinical situations. Objectives To study the accuracy and consistency of anti-Xa assays for rivaroxaban plasma concentration in a prospective, multicenter evaluation study employing different reagents and analytical platforms. Methods Rivaroxaban 20 mg was administered once daily to 20 healthy volunteers and blood samples were taken at peak and trough levels (clinicaltrials.gov NCT01710267). Anti-Xa activity was determined in 10 major laboratories using different reagents and analyzers; corresponding rivaroxaban plasma concentrations were measured by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS). Findings Overall Pearson's correlation coefficient of anti-Xa levels and HPLC-MS results was 0.99 for Biophen® Heparin (95% CI, 0.99, 0.99), Biophen® DiXaI (95% CI, 0.99, 0.99) and STA® anti-Xa liquid (95% CI, 0.99, 1.00). Correlation was lower in rivaroxaban concentrations below 50 µg L-1 and above 200 µg L-1 . The overall bias of the Bland-Altman difference plot was 14.7 µg L-1 for Biophen Heparin, 17.9 µg L-1 for Biophen DiXal and 19.0 µg L-1 for STA anti-Xa liquid. Agreement between laboratories was high at peak level but limited at trough level. Conclusions Anti-Xa activity correlated well with rivaroxaban plasma concentrations, especially in a range between 50 and 200 µg L-1 . However, anti-Xa assays systematically overestimated rivaroxaban concentration as compared with HPLC-MS, particularly at higher concentrations. This overestimation, coupled with an apparent interindividual variation, might affect the interpretation of results in some situations.


Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Monitoramento de Medicamentos/métodos , Inibidores do Fator Xa/sangue , Fator Xa/metabolismo , Rivaroxabana/sangue , Administração Oral , Adolescente , Adulto , Idoso , Cromatografia Líquida de Alta Pressão , Inibidores do Fator Xa/administração & dosagem , Voluntários Saudáveis , Humanos , Ensaio de Proficiência Laboratorial , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos Testes , Rivaroxabana/administração & dosagem , Suíça , Espectrometria de Massas em Tandem , Adulto Jovem
14.
Clin Nephrol ; 66(4): 247-55, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17063991

RESUMO

UNLABELLED: The aim of this study was to evaluate the prevalence of vitamin D deficiency in chronic renal failure (CRF) patients on peritoneal dialysis (PD) and to correlate the findings with various demographic and renal osteodystrophy markers. METHOD: This cross-sectional, multicenter study was carried out in 273 PD patients with a mean age of 61.7 +/- 10.9 years and mean duration of PD 3.3 +/- 2.2 years. It included 123 female and 150 male patients from 20 centers in Greece and Turkey, countries that are on the same latitude, namely, 36-42 degrees north. We measured 25(OH)D3 and 1.25(OH)2D3 levels and some other clinical and laboratory indices of bone mineral metabolism. RESULTS: Of these 273 patients 92% (251 patients) had vitamin D deficiency i.e. serum 25(OH)D3 levels less than 15 ng/ml, 119 (43.6%) had severe vitamin D deficiency i.e., serum 25(OH)D3 levels, less than 5 ng/ml, 132 (48.4%) had moderate vitamin D deficiency i.e., serum 25(OH)D3 levels, 5-15 ng/ml, 12 (4.4%) vitamin D insufficiency i.e., serum 25(OH)D3 levels 15 - 30 ng/ml and only 10 (3.6%) had adequate vitamin D stores. We found no correlation between 25(OH)D3 levels and PTH, serum albumin, bone alkaline phosphatase, P, and Ca x P. In multiple regression analyses, the independent predictors of 25(OH)D3 were age, presence of diabetes (DM-CRF), levels of serum calcium and serum 1.25(OH)2D3. CONCLUSION: We found a high prevalence (92%) of vitamin D deficiency in these 273 PD patients, nearly one half of whom had severe vitamin D deficiency. Vitamin D deficiency is more common in DM-CRF patients than in non-DM-CRF patients. Our findings suggest that these patients should be considered for vitamin D supplementation.


Assuntos
Falência Renal Crônica/complicações , Diálise Peritoneal/efeitos adversos , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/etiologia , Adulto , Idoso , Estudos Transversais , Nefropatias Diabéticas/terapia , Feminino , Humanos , Falência Renal Crônica/etiologia , Masculino , Pessoa de Meia-Idade , Vitamina D/sangue , Deficiência de Vitamina D/epidemiologia
15.
Int J Obstet Anesth ; 26: 79-82, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26775898

RESUMO

Heparin-induced thrombocytopenia is a serious adverse event of anticoagulation with a high risk of thromboembolic complications. As a consequence, anticoagulants other than heparins must be administered. These may be unavailable, contraindicated during pregnancy, off-label, impractical due to short half-lives and, most importantly, may be unfamiliar to many anesthesiologists. Impaired coagulation bears the risk of adverse events following neuraxial procedures and of peripartum hemorrhage. We describe the case of heparin-induced thrombocytopenia in a 29-year-old pregnant woman at 27weeks of gestation with severe valvular heart disease.


Assuntos
Heparina/efeitos adversos , Complicações Hematológicas na Gravidez/induzido quimicamente , Trombocitopenia/induzido quimicamente , Adulto , Feminino , Humanos , Gravidez
16.
Oxid Med Cell Longev ; 2016: 1507270, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27313824

RESUMO

Background. Oxidative stress is a hallmark of CKD and this alteration is strongly implicated in LV hypertrophy and in LV dysfunction. Methods and Patients. We resorted to the strongest genetic biomarker of paraoxonase-1 (PON1) activity, the Q192R variant in the PON1 gene, to unbiasedly assess (Mendelian randomization) the cross-sectional and longitudinal association of this gene-variant with LV mass and function in 206 CKD patients with a 3-year follow-up. Results. The R allele of Q192R polymorphism associated with oxidative stress as assessed by plasma 8-isoPGF2α (P = 0.03) and was dose-dependently related in a direct fashion to LVMI (QQ: 131.4 ± 42.6 g/m(2); RQ: 147.7 ± 51.1 g/m(2); RR: 167.3 ± 41.9 g/m(2); P = 0.001) and in an inverse fashion to systolic function (LV Ejection Fraction) (QQ: 79 ± 12%; RQ: 69 ± 9%; RR: 65 ± 10% P = 0.002). On longitudinal observation, this gene variant associated with the evolution of the same echocardiographic indicators [LVMI: 13.40 g/m(2) per risk allele, P = 0.005; LVEF: -2.96% per risk allele, P = 0.001]. Multivariate analyses did not modify these associations. Conclusion. In CKD patients, the R allele of the Q192R variant in the PON1 gene is dose-dependently related to the severity of LVH and LV dysfunction and associates with the longitudinal evolution of these cardiac alterations. These results are compatible with the hypothesis that oxidative stress is implicated in cardiomyopathy in CKD patients.


Assuntos
Arildialquilfosfatase/genética , Cardiomiopatias/etiologia , Estresse Oxidativo , Insuficiência Renal Crônica/genética , Idoso , Alelos , Estudos Transversais , Ecocardiografia , Feminino , Genótipo , Taxa de Filtração Glomerular , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Polimorfismo de Nucleotídeo Único , Insuficiência Renal Crônica/complicações , Função Ventricular Esquerda/fisiologia
18.
Bone Marrow Transplant ; 36(11): 993-1000, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16184183

RESUMO

We studied occurrence, risk factors and outcome of patients with transplant-associated microangiopathy (TAM) after allogeneic stem cell transplantation (HSCT). A total of 221 consecutive patients were transplanted between 1995 and 2002. TAM is defined as evidence of hemolysis and schistocytes in the first 100 days. Outcomes analyzed included TAM and overall survival. Of 221 patients, 68 had TAM. The cumulative incidence was 31 (25-38)% at 100 days. Patients with TAM had higher LDH, higher bilirubin, higher creatinine and more often neurologic symptoms. TAM was not associated with stem cell source, cyclosporine levels and was not more frequent in recent years. In multivariate analysis, risk factors for TAM included donor type, age, gender, ABO-incompatibility and acute graft-versus-host disease (aGvHD). In patients with TAM, 1-year survival was lower than in patients without TAM (27 +/- 18% for TAM with high schistocyte counts; 53 +/- 15% for TAM with low schistocyte counts; vs 78 +/- 7% in patients without TAM; P<0.0001). TAM was independently associated with mortality adjusting for donor type, age and aGvHD occurrence and severity. TAM is frequent after HSCT and is associated with mortality even after adjustment for aGvHD grade. Risk factors of TAM are similar to aGvHD. TAM may represent endothelial damage driven by donor-host interactions.


Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Síndrome Hemolítico-Urêmica/etiologia , Adolescente , Adulto , Criança , Pré-Escolar , Eritrócitos Anormais , Feminino , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/mortalidade , Neoplasias Hematológicas/terapia , Transplante de Células-Tronco Hematopoéticas/mortalidade , Hemólise , Síndrome Hemolítico-Urêmica/diagnóstico , Síndrome Hemolítico-Urêmica/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Análise de Sobrevida , Transplante Homólogo , Resultado do Tratamento
20.
Ther Umsch ; 62(1): 23-7, 2005 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-15702703

RESUMO

Anticoagulants and antiplatelet agents are currently used during pregnancy as treatment or prophylaxis for thromboembolic disease. Main adverse events of these agents are bleeding episodes, which put the pregnancy at risk. Unfractionated and low molecular weight heparins are first-line treatment or prophylaxis for thromboembolism. If an antiplatelet agent is needed, aspirin alone or in combination with heparins can be safely administered. Coumarine derivatives are still contraindicated during pregnancy because of teratogenicity and/or bleeding. No adequate data are yet available on the safety profile of the new antiplatelet agents or the direct thrombin inhibitors. Special considerations are discussed on the risks of regional anesthesia, as well as on nursing during anticoagulation.


Assuntos
Anticoagulantes/administração & dosagem , Anticoagulantes/efeitos adversos , Hemorragia/induzido quimicamente , Inibidores da Agregação Plaquetária/administração & dosagem , Inibidores da Agregação Plaquetária/efeitos adversos , Complicações na Gravidez/tratamento farmacológico , Medição de Risco/métodos , Tromboembolia/tratamento farmacológico , Anticoagulantes/classificação , Feminino , Humanos , Inibidores da Agregação Plaquetária/classificação , Guias de Prática Clínica como Assunto , Padrões de Prática Médica , Gravidez , Fatores de Risco , Tromboembolia/prevenção & controle , Saúde da Mulher
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