RESUMO
BACKGROUND AND STUDY AIMS: Flat lesions pose new challenges for endoscopists, but the importance of detecting them is still controversial. Most screening studies do not survey macroscopic polyp morphology. The aims were to evaluate the percentage of flat polyp findings in a large asymptomatic adult screening population (n = 52 521), to assess the impact of shape and size on malignant transformation, and to assess the role of flat lesions regarding quality assurance in colorectal cancer prevention. MATERIAL AND METHODS: Retrospective analysis of screening colonoscopies performed between 2007 and 2011 according to the Austrian "Quality management for colon cancer prevention" program. RESULTS: 17 771 patients with polyps were included in the study. Patients with flat polyps represented 24.2 % (n = 4293), 62.4 % (n = 11 097) were classified as having sessile and 13.4 % (n = 2381) as pedunculated polyps. Among those with flat polyps 51.4 % had adenomas (n = 2207). High grade dysplasia (HGD) was found in 2.1 % (n = 47) of flat adenomas, in 1.5 % (n = 89) of sessile adenomas and 4.7 % (n = 92) of pedunculated adenomas (P < 0.0001. The risk for containing HGD was 1.0 % for flat lesions ≤ 10 mm in size compared with 10.3 % for lesions > 10 mm, and 1.0 % for polypoid lesions ≤ 10 mm compared with 9.3 % for lesions > 10 mm (P < 0.0001). Multivariable logistic regression showed that polyp size (P < 0.0001) but not polyp shape (P = 0.438) is an independent predictor for HGD. Adenoma detection rate (ADR) correlated weakly with the flat polyp detection rate (Pearson r = 0.24). CONCLUSION: Malignant potential of polyps is mostly affected by size but not by shape. Since flat polyp detection rate only correlates poorly with ADR we do not recommend its incorporation in quality assured screening colonoscopy.
Assuntos
Adenoma/patologia , Pólipos do Colo/patologia , Colonoscopia/normas , Neoplasias Colorretais/patologia , Idoso , Colonoscopia/estatística & dados numéricos , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Melhoria de Qualidade , Estudos RetrospectivosRESUMO
BACKGROUND: Arterial catheterization is painful and is associated with patient stress and anxiety. Analgesia is usually provided by subcutaneous injection of local anaesthetic. An alternative is topical anaesthesia, such as Rapydan which is a novel topical anaesthetic patch containing 70 mg each of lidocaine and tetracaine. We therefore tested the hypothesis that Rapydan patch analgesia is non-inferior to subcutaneous local anaesthetic. METHODS: Ninety patients undergoing elective major cardiac surgery were included in this prospective, double-blind clinical trial. Patients were randomly assigned to receive either a lidocaine/tetracaine patch, followed by subcutaneous injection 0.5 ml of normal saline solution, or placebo patch with subsequent subcutaneous injection of 0.5 ml of lidocaine 1%. Pain during arterial catheterization using 100-mm-long visual analogue scale (VAS) was the primary outcome. Other outcomes were pain during anaesthetic/saline injection and plasma tetracaine concentrations. RESULTS: VAS pain scores during arterial puncture were comparable in both groups and Rapydan was non-inferior to subcutaneous lidocaine. Pain scores at the time of subcutaneous injection were significantly lower (better) in patients assigned to the lidocaine/tetracaine patch than to lidocaine (P=0.001). Plasma tetracaine concentrations never exceeded the detection limit of 25 ng ml(-1) at any time in any patient. CONCLUSIONS: Both the lidocaine/tetracaine patch and subcutaneous injection of lidocaine provided comparable pain control during arterial catheter insertion. Subcutaneous lidocaine caused discomfort during injection, whereas the lidocaine/tetracaine patch required placement 20 min before the procedure. Given adequate time, the patch provided better overall analgesia by obviating the need for subcutaneous infiltration.
Assuntos
Anestésicos Locais/administração & dosagem , Cateterismo Venoso Central/efeitos adversos , Lidocaína/administração & dosagem , Dor/prevenção & controle , Tetracaína/administração & dosagem , Adesivo Transdérmico , Administração Cutânea , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anestesia Local/métodos , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Estudos Prospectivos , Adulto JovemRESUMO
OBJECTIVE: Patients with cancer are at an increased risk for venous thromboembolism (VTE). Clotting factor VIII activity (FVIII) has been established as risk factor of primary and recurrent VTE. We investigated FVIII as predictive parameter of VTE in cancer patients. METHODS AND RESULTS: The prospective observational Cancer and Thrombosis Study (CATS) includes patients with newly diagnosed cancer or disease progression, study end point is symptomatic VTE. FVIII was measured on a Sysmex CA 7000 analyzer. Data on 840 patients (median age: 62 years, 25th to 75th percentile 53 to 68, 378 women) were available for analyses, of these 111 patients had hematologic malignancies and 729 solid cancer. During a median observation time of 495 days 62 events occurred. Cumulative probability of VTE after 6 months was 14% in patients with elevated FVIII-levels and 4% in those with normal levels (P=0.001). The association was strongest in younger patients: whereas in 40-year-old patients a 2-fold VTE risk per factor VIII increase of 20% was observed (HR=2.0 [95% CI: 1.5 to 2.7], P<0.0001), this association was still present but attenuated in older patients. CONCLUSIONS: FVIII is independently associated with an increased risk of VTE in cancer patients. The association between FVIII and VTE risk declines with increasing age.
Assuntos
Fator VIII/metabolismo , Neoplasias/sangue , Neoplasias/complicações , Tromboembolia Venosa/sangue , Tromboembolia Venosa/etiologia , Fatores Etários , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Fatores de TempoRESUMO
Calcineurin-inhibitor therapy can lead to renal dysfunction in heart transplantation patients. The novel immunosuppressive (IS) drug sirolmus (Srl) lacks nephrotoxic effects; however, proteinuria associated with Srl has been reported following renal transplantation. In cardiac transplantation, the incidence of proteinuria associated with Srl is unknown. In this study, long-term cardiac transplant patients were switched from cyclosporine to Srl-based IS. Concomitant IS consisted of mycophenolate mofetil +/- steroids. Proteinuria increased significantly from a median of 0.13 g/day (range 0-5.7) preswitch to 0.23 g/day (0-9.88) at 24 months postswitch (p = 0.0024). Before the switch, 11.5% of patients had high-grade proteinuria (>1.0 g/day); this increased to 22.9% postswitch (p = 0.006). ACE inhibitor and angiotensin-releasing blocker (ARB) therapy reduced proteinuria development. Patients without proteinuria had increased renal function (median 42.5 vs. 64.1, p = 0.25), whereas patients who developed high-grade proteinuria showed decreased renal function at the end of follow-up (median 39.6 vs. 29.2, p = 0.125). Thus, proteinuria may develop in cardiac transplant patients after switch to Srl, which may have an adverse effect on renal function in these patients. Srl should be used with ACEi/ARB therapy and patients monitored for proteinuria and increased renal dysfunction.
Assuntos
Transplante de Coração/imunologia , Imunossupressores/efeitos adversos , Proteinúria/induzido quimicamente , Sirolimo/efeitos adversos , Corticosteroides/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Ensaios Clínicos como Assunto , Quimioterapia Combinada , Monitoramento Ambiental , Feminino , Transplante de Coração/mortalidade , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Imunossupressores/uso terapêutico , Masculino , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/uso terapêutico , Seleção de Pacientes , Estudos Prospectivos , Sirolimo/farmacocinética , Sirolimo/uso terapêutico , Análise de SobrevidaRESUMO
BACKGROUND: Patients with cancer are at an increased risk for venous thromboembolism (VTE). The risk varies markedly in different patient populations. Factor V (FV) Leiden is the most common genetic risk factor for VTE, and the impact of FV Leiden on cancer-associated thrombosis is not yet fully elucidated. OBJECTIVE: To study the impact of FV Leiden on the risk of thrombosis in cancer patients. METHODS: In the prospective observational Vienna Cancer And Thrombosis Study (CATS), 982 patients were included and were followed until occurrence of VTE or death, for a maximum period of 2 years. FV Leiden was determined by genotyping at inclusion. Main outcome measures were symptomatic or lethal objectively confirmed VTE. RESULTS: Of the 982 patients, FV Leiden was diagnosed in 72 (7.3%, 70 were heterozygous and 2 were homozygous). Ten of 72 (13.9%) patients with FV Leiden developed VTE, whereas this was the case in 69 of 910 (7.6%) patients without FV Leiden. In multivariate analysis that included age, sex, different tumor types, tumor stage, newly diagnosed vs. recurrence of disease, and the treatment modalities, the hazard ratio was 2.0 (95% confidence interval 1.0-4.0). In Kaplan-Meier analysis, the probability for development of VTE was 13% in those with and 5.7% in those without FV Leiden after 6 months; after 1 year, the corresponding risks were 15% and 7.3%. CONCLUSIONS: FV Leiden is a genetically determined and thus disease-independent parameter, which is associated with VTE in cancer patients and could therefore be used for individual risk assignment.
Assuntos
Resistência à Proteína C Ativada/genética , Fator V/genética , Mutação , Neoplasias/complicações , Tromboembolia Venosa/etiologia , Resistência à Proteína C Ativada/sangue , Resistência à Proteína C Ativada/complicações , Resistência à Proteína C Ativada/diagnóstico , Resistência à Proteína C Ativada/mortalidade , Idoso , Áustria , Análise Mutacional de DNA , Feminino , Predisposição Genética para Doença , Heterozigoto , Homozigoto , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Neoplasias/diagnóstico , Neoplasias/mortalidade , Fenótipo , Modelos de Riscos Proporcionais , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/genética , Tromboembolia Venosa/mortalidadeRESUMO
BACKGROUND: The incidence of venous thromboembolism (VTE) is increased among cancer patients. OBJECTIVE: We assessed serum levels of C-reactive protein (CRP) in order to study their prognostic significance for VTE and survival in the prospective observational Cancer and Thrombosis Study (CATS). PATIENTS AND METHODS: This study includes patients with recently diagnosed cancer or progression of disease after remission. Occurrence of VTE and information on the patients' anti-cancer-treatment are recorded. Observation ends with occurrence of objectively confirmed VTE, death or after 2 years. CRP levels were determined by an immunonephelometric method. RESULTS: We included 705 consecutive patients with solid tumors. During the observation period, VTE occurred in 43 (6.1%) patients and 413 (58.6%) died. The cumulative probability of VTE was 6.6% after 1 year. In univariate analysis, CRP (as metric variable, per double increase) was associated with VTE [hazard ratio (HR) 1.2, 95% confidence interval (CI) 1.1-1.3 P = 0.048]. However, in multivariable analysis including chemotherapy, surgery and radiotherapy, metastasis, cancer-site and sP-selectin the association with VTE (HR 1.0, 95% CI 0.9-1.2 P = 0.932) was no longer observed. CRP was clearly associated with worse survival probability with a HR of 1.3 (95% CI 1.2-1.3, P < 0.0001) in multivariable analysis. The cumulative survival after 12 months was 43% in patients with CRP above the 75th percentile (1.8 mg dL(-1) ) and 82% in those below the 75th percentile. CONCLUSIONS: In cancer patients elevated CRP was not independently associated with VTE. CRP was significantly associated with worse survival.
Assuntos
Proteína C-Reativa/metabolismo , Neoplasias/complicações , Tromboembolia Venosa/etiologia , Idoso , Áustria , Biomarcadores/sangue , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Neoplasias/imunologia , Neoplasias/mortalidade , Nefelometria e Turbidimetria , Selectina-P/sangue , Modelos de Riscos Proporcionais , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Taxa de Sobrevida , Fatores de Tempo , Regulação para Cima , Tromboembolia Venosa/sangue , Tromboembolia Venosa/imunologia , Tromboembolia Venosa/mortalidadeRESUMO
Venous thromboembolism (VTE) is a life-threatening complication in cancer patients. Identification of risk factors has been in focus in the past years. Functional single nucleotide polymorphisms (SNP) of coagulation factors known to influence the concentration or function may be considered to influence the risk of VTE in cancer patients. We evaluated the influence of fibrinogen plasma levels, the -455G>A SNP in the fibrinogen beta gene and the Val34Leu (163G>T) SNP in the factor XIII A-subunit (FXIII-A) gene on the risk of VTE. In 1,079 tumour patients recruited for the prospective Vienna Cancer and Thrombosis Study (CATS) fibrinogen levels were determined by the Clauss method. The FXIII-A Val34Leu and the fibrinogen -455G>A SNPs were tested by allele-specific PCR. The median follow-up time was 604 days, 83 thrombotic events occurred. The median fibrinogen level was 381 mg/dl (25th-75th percentile: 312 to 467). In a multivariable Cox model adjusted to chemotherapy, surgery, radiotherapy, age and sex, neither the fibrinogen concentration (hazard ratio [HR] =1.05, confidence interval [CI] 0.839-1.310 p=0.68), nor the -455G>A SNP (HR=0.77, 95%CI 0.491-1.197; p=0.24), nor the Val34Leu SNP (HR=0.99, 95%CI 0.646-1.542 p=0.99) were associated with occurrence of VTE. The fibrinogen concentration was not significantly different among the fibrinogen -455G or A genotype carriers (p = 0.33). Disseminated intravascular coagulation was observed in only five patients, none of these developed VTE. In conclusion, fibrinogen plasma levels, the fibrinogen -455G>A and the FXIII-A Val34Leu polymorphisms were not associated with VTE in our study.
Assuntos
Coagulação Sanguínea/genética , Fator XIII/genética , Fibrinogênio/genética , Neoplasias/genética , Polimorfismo de Nucleotídeo Único , Tromboembolia Venosa/genética , Idoso , Análise de Variância , Áustria , Biomarcadores/sangue , Feminino , Fibrinogênio/análise , Predisposição Genética para Doença , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Neoplasias/complicações , Neoplasias/terapia , Fenótipo , Reação em Cadeia da Polimerase , Modelos de Riscos Proporcionais , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Tromboembolia Venosa/sangueRESUMO
AIM: The aim of this paper was to evaluate gender-related differences in patients undergoing mechanical aortic valve replacement with the CarboMedics valve. METHODS: During a 20 year period, 629 patients (median age 60 years) underwent mechanical aortic valve replacement with the CarboMedics valve. Of these, 215 patients were female (34%). The median follow-up for the entire cohort was 10.2 ± 6.2 years. RESULTS: In-hospital mortality for the entire cohort was 9% (male 7.3% vs. female 11.0%, P=0.005). Cox regression analysis revealed redo-surgery (HR=2.35, CI 1.35-4.08), LVEF<30% (HR=2.31, CI 1.36-3.93), age (HR=1.60, CI 1.27-2.02), as well as female gender (HR=2.07, CI 1.28-3.35) as independent predictors of survival. For male gender LVEF<30% (HR=2.47, CI 1.23-4.93) and age (HR=1.75, CI 1.25-2.43) were independent predictors of survival. For female gender, additional CABG (HR=2.15, CI 1.08-4.28), redo surgery (HR=3.64, CI 1.78-7.46) as well as age (HR=1.48, CI 1.06-2.06) were independent predictors of survival. CONCLUSION: Gender per se is an independent risk factor of survival after mechanical aortic valve replacement. Severely impaired LVEF independently predicts survival in males whereas additional CABG and redo surgery do in females. Age affects survival in both sexes. These findings may serve as a basis for further improving gender related outcome.
Assuntos
Estenose da Valva Aórtica/cirurgia , Valva Aórtica/cirurgia , Implante de Prótese de Valva Cardíaca/instrumentação , Próteses Valvulares Cardíacas , Fatores Etários , Idoso , Estenose da Valva Aórtica/mortalidade , Estenose da Valva Aórtica/fisiopatologia , Áustria , Distribuição de Qui-Quadrado , Ponte de Artéria Coronária/efeitos adversos , Feminino , Implante de Prótese de Valva Cardíaca/efeitos adversos , Implante de Prótese de Valva Cardíaca/mortalidade , Mortalidade Hospitalar , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Desenho de Prótese , Análise de Regressão , Reoperação , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores Sexuais , Volume Sistólico , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Disfunção Ventricular Esquerda/mortalidade , Disfunção Ventricular Esquerda/fisiopatologia , Função Ventricular EsquerdaRESUMO
BACKGROUND: In cancer patients, laboratory parameters that predict venous thromboembolism (VTE) are scarce. Increased platelet count has been found to be a risk factor for VTE in cancer patients receiving chemotherapy (CHT). We have assessed high platelet count as a risk predictor for VTE in patients with cancer undergoing discriminative anti-cancer treatments and investigated whether platelet count correlates with thrombopoietin (TPO) levels. DESIGN AND METHODS: The Cancer and Thrombosis Study (CATS) is an ongoing prospective observational study of patients with newly diagnosed cancer or progression of disease, which started in October 2003. Occurrence of VTE and information on the patients' anti-cancer treatment during follow-up were recorded. RESULTS: Between October 2003 and February 2008, 665 patients with solid tumors were included (314 female/351 male, mean age 62 years). VTE occurred in 44 patients (18 female/26 male, mean age 62 years). The cumulative probability of VTE after 1 year was 34.3% in patients with a platelet count (PC) above the 95th percentile representing 443 x 10(9)/L compared with 5.9% in those below 443 x 10(9)/L. High platelet count [hazard ratio (HR): 3.50, 95% confidence interval (CI): 1.52-8.06, P = 0.0032], soluble P-selectin [HR: 2.66, 95% CI: 1.42-4.96, P = 0.0021] and surgery [HR: 4.05, 95% CI: 1.74-9.46, P = 0.0012] were statistically significant risk factors for VTE in multivariable analysis along with leucocyte count, age, gender, radio- and CHT. We found no correlation between platelet count and TPO levels. CONCLUSIONS: High PC is a clinically important, independent risk predictor for VTE in cancer patients. PC was not found to be associated with TPO levels.
Assuntos
Coagulação Sanguínea , Neoplasias/complicações , Contagem de Plaquetas , Tromboembolia Venosa/etiologia , Idoso , Áustria , Biomarcadores/sangue , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Neoplasias/terapia , Selectina-P/sangue , Modelos de Riscos Proporcionais , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Trombopoetina/sangue , Fatores de Tempo , Tromboembolia Venosa/sangueRESUMO
BACKGROUND: The increasingly recognized prognostic impact of the strong ion gap in critical illness is in contrast to its largely unknown chemical nature. Experimental and clinical evidence suggest that acute phase proteins might account for elevation of the strong ion gap. The hypothesis of this investigation was that acute phase proteins account for strong ion gap in critically ill patients. MATERIALS AND METHODS: The charges of the two acute phase proteins C-reactive protein and fibrinogen were estimated by a computer model. Additionally, 142 patients admitted to a medical intensive care unit of a university hospital were studied prospectively during a six month period. Serial daily observations were recorded and classified according to the systemic inflammatory state. The acute phase proteins C-reactive protein and fibrinogen were measured and the strong ion gap was calculated from the measured acid-base variables. RESULTS: The approximated mean charges of C-reactive protein and fibrinogen at a pH of 7.4 are -4.0 and -13.6 per molecule, respectively. Therefore, their negative charge is too small to explain the elevated strong ion gap even during a substantial increase of C-reactive protein and fibrinogen due to an acute-phase reaction. Moreover, C-reactive protein did not correlate with the strong ion gap when partialized for creatinine (R = 0.02, P = 0.567). Fibrinogen did not correlate with the strong ion gap. Creatinine correlated with the strong ion gap (R = 0.42, P < 0.001). Neither systemic inflammatory state nor increasing C-reactive protein levels were associated with an increasing strong ion gap. CONCLUSION: Acute phase proteins do not account for an elevated strong ion gap in critically ill patients.
Assuntos
Equilíbrio Ácido-Base , Ânions/análise , Gasometria/métodos , Proteína C-Reativa/análise , Fibrinogênio/análise , Concentração de Íons de Hidrogênio , Desequilíbrio Ácido-Base/sangue , Adulto , Idoso , Ânions/sangue , Dióxido de Carbono/sangue , Simulação por Computador , Estado Terminal , Interpretação Estatística de Dados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos ProspectivosRESUMO
BACKGROUND: Knowledge of platelet function may assist in patient care in chronic autoimmune thrombocytopenia (cAITP). MATERIALS AND METHODS: We evaluated the association of platelet function with haemorrhage in 41 patients, median age 41 years (range 14-82 years, 24 females) with chronic autoimmune thrombocytopenia (cAITP). Samples were investigated for platelet P-selectin, and adhesion and aggregate formation under high shear conditions. Data were compared to those from 28 healthy controls (median age 39 years, range 23-70 years, 17 females) and correlated with a bleeding score of 0 (no bleeding) to 3 (overt mucosal bleedings). RESULTS: P-selectin levels were higher in patients than in controls (P < 0.0004). Compared to controls, the patients' samples responded to high shear with decreased adhesion to the polystyrene surface (P < 0.0001), but formed aggregates of normal size. P-selectin expression was neither correlated with platelet counts, nor platelet adhesion, nor the bleeding score. Only the size of formed aggregates correlated with P-selectin (P = 0.01). Platelet counts (odds ratio 0.5, 95% confidence interval 0.22-0.88; P = 0.04) and adhesion (odds ratio 0.45, 95% confidence interval 0.17-0.87; P = 0.04) were independently inversely correlated with bleeding symptoms. CONCLUSION: Platelet adhesion correlates with bleeding symptoms, while the size of aggregates that are formed under high shear correlates with in vivo platelet activation. The determination of these parameters may assist in estimating an individual bleeding risk and thus a decision for treatment.
Assuntos
Testes de Coagulação Sanguínea/métodos , Adesividade Plaquetária/imunologia , Agregação Plaquetária/imunologia , Testes de Função Plaquetária/métodos , Púrpura Trombocitopênica Idiopática/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Tempo de Sangramento , Ensaios Clínicos Controlados como Assunto , Feminino , Hemorragia/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Fatores de Risco , Índice de Gravidade de DoençaRESUMO
Lupus anticoagulants (LA) prolong in vitro phospholipid-dependent coagulation tests, but are associated with thromboembolic disease (TE). However, a subgroup of individuals with LA has no TE, and it is therefore desirable to distinguish those at risk for TE from those without. Whether platelets have a primary role in the development of TE is not clear yet. We determined platelet autoantibodies to identify a specific platelet target which is associated with platelet activation in 97 patients with a long history of detectable LA, 65 patients with TE (LA/TE+), and 32 individuals without TE (LA/TE-). Thrombocytopenia was more common in the LA/TE- than in the LA/TE+ group (P < 0.05). Both groups had platelet antibodies, but the frequency of antibodies was lower in LA/TE+ than LA/TE- patients (P < 0.01), who had higher antibody titres against glycoprotein IIb/IIIa and glycoprotein Ib/IX (P < 0.05). Also, their platelets were more activated, as determined by PAC-1 binding (P < 0.01). These differences were also noted if patients with arterial thrombosis were evaluated separately. These findings in LA/TE- individuals were similar to those in patients with chronic autoimmune thrombocytopenia. However, there was no autoantibody target identifiable to distinguish between LA/TE- from LA-TE+ individuals. We therefore conclude that the presence of platelet antibodies, even if associated with platelet activation, is not sufficient to dispose LA patients to thromboembolic disease.
Assuntos
Autoanticorpos/imunologia , Plaquetas/imunologia , Inibidor de Coagulação do Lúpus/imunologia , Ativação Plaquetária , Tromboembolia/imunologia , Adolescente , Adulto , Idoso , Síndrome Antifosfolipídica/imunologia , Testes de Coagulação Sanguínea , Criança , Feminino , Humanos , Pessoa de Meia-Idade , Glicoproteínas da Membrana de Plaquetas/imunologia , Distribuição Aleatória , Trombocitopenia/imunologia , beta 2-Glicoproteína I/imunologiaRESUMO
BACKGROUND: Plasma haptoglobin determination is clinically used as parameter for haemolysis. To date, however, the influence of the mode of haemolysis (extravascular vs. intravascular) and of nonhaemolytic conditions on haptoglobin concentration and its reliability as a haemolysis marker remain poorly defined. MATERIALS AND METHODS: In a total of 479 individuals, the influence of haemolytic and nonhaemolytic conditions on plasma haptoglobin levels was investigated. RESULTS: All studied types of haemolytic disease (n = 16) were associated with markedly decreased plasma haptoglobin levels, without significant differences between intravascular vs. predominantly extravascular haemolysis. Diminished haptoglobin values were also observed in patients with liver cirrhosis, which normalized after liver transplantation. In contrast, markedly increased haptoglobin levels were found in patients with inflammation. In patients with haemolysis and a concomitant acute-phase response, however, haemolysis-dependent haptoglobin depletion was not attenuated. Interestingly, patients with a strongly positive direct antiglobulin test or high cold agglutinin titre but no further evidence for haemolysis had normal haptoglobin values. Likewise, anaemia owing to bone marrow failure, acute gastrointestinal or chronic diffuse blood loss, and end-stage kidney disease were associated with normal haptoglobin levels. CONCLUSIONS: Plasma haptoglobin depletion is a reliable marker for the instant diagnosis of accelerated red cell destruction irrespective of the site of haemolysis or the presence of inflammation. The capacity of this parameter to predict haemolysis appears to be limited in patients with liver cirrhosis and decreased haptoglobin production only.