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BACKGROUND: Identification, quantification and typing of M-Proteins (MP) play an important role in the diagnosis, classification and monitoring of monoclonal gammopathies both of malignant origin (eg. Multiple Myeloma) and of unknown origin. Previous evidence attests that MGUS (Monoclonal Gammopathy of Undetermined Significance) detected by agarose gel electrophoresis has a prevalence of 3.2% in the general population. Therefore, our study aimed to verify this data by means of capillary zone electrophoresis (CZE). METHODS: CZE was performed to evaluate the prevalence of M-Protein (MP) in 44.474 consecutive outpatients of all ages with a prescription for serum protein electrophoresis over a 2-year period (2008 and 2009). All MPs that were identified were then typed by immunofixation electrophoresis on agarose gel (IFE). RESULTS: In subjects aged over 50 (23.408, i.e., 52.6% of the whole cohort) MP ≤30 g/L (MGUS) was identified in 6.0% of cases, with a frequency nearly double than that previously reported. The population was then divided into ten-year age groups: the 71-80 age group had the highest percentage of MP (29%), followed by 61-70 (27%), 51-60 (18%), 81-90 (12%), 41-50 (8%), 31-40 (3%), >90 (2%) and <30 (1%). The frequency of MP types (IFE) was the same in each age group, with IgG Kappa being the most represented class. CONCLUSIONS: According to the high MGUS prevalence observed in this study, these results may be useful especially for general practitioners, because the identification even of small MP (analytical sensitivity: 0.5 g/L) may help optimize clinical management.
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The evaluation of patients admitted at the emergency department (ED) for chest pain is challenging and involves many different clinical specialists including emergency physicians, laboratory professionals and cardiologists. The preferable approach to deal with this issue is to develop joint protocols that will assist the clinical decision-making to quickly and accurately rule-out patients with non life-threatening conditions that can be considered for early and safe discharge or further outpatient follow-up, rule-in patients with acute coronary syndrome and raise the degree of alert of the emergency physicians on non-cardiac life-threatening emergencies. The introduction of novel biomarkers alongside the well-established troponins might support this process and also provide prognostic information about acute short-term or chronic long-term risk and severity. Among the various biomarkers, copeptin measurement holds appealing perspectives. The utility of combining troponin with copeptin might be cost-effective due to the high negative predictive value of the latter biomarker in the rule-out of an acute coronary syndrome. Moreover, in the presence of a remarkably increased concentration (e.g., more than 10 times the upper limit of the reference range), to reveal the presence of acute life-threatening conditions that may not necessarily be identified with the use of troponin alone. The aim of this article is to review current evidence about the clinical significance of copeptin testing in the ED as well as its appropriate placing within diagnostic protocols.
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Síndrome Coronario Agudo/diagnóstico , Biomarcadores/sangre , Dolor en el Pecho , Servicio de Urgencia en Hospital , Glicopéptidos/sangre , Troponina/sangre , Dolor en el Pecho/sangre , Servicio de Urgencia en Hospital/economía , Humanos , Alta del Paciente , Factores de Riesgo , Índice de Severidad de la EnfermedadRESUMEN
BACKGROUND: The prognostic value of natriuretic peptide elevations in patients with acute coronary syndromes (ACS) is still incompletely defined. We measured N-terminal pro-brain natriuretic peptide (NT-proBNP) on admission in patients with ACS and ECG evidence of myocardial ischemia. METHODS AND RESULTS: The NT-proBNP was measured at a median time of 3 hours after symptom onset in 1756 patients. The outcome measure was death at 30 days, which occurred in 113 patients (6.4%). The median NT-proBNP level was 353 ng/L (107 to 1357 ng/L). Compared with the lowest quartile, patients in the second, third, and fourth quartiles had a relative risk of subsequent death of 2.94 (95% CI, 1.15 to 7.52), 5.32 (95% CI, 2.19 to 12.91), and 11.5 (95% CI, 4.90 to 26.87), respectively. The NT-proBNP was independently associated with death in a logistic regression model, which included clinical variables, ECG, and troponin T in patients either with (OR of highest versus lowest quartile, 7.0; 95% CI, 1.9 to 25.6) or without (OR of highest versus lowest quartile, 4.1; 95% CI, 1.1 to 14.6) persistent ST-segment elevation. NT-proBNP was also an independent predictor of severe heart failure. CONCLUSIONS: The measurement of NT-proBNP on admission improves the early risk stratification of patients with ACS, suggesting the need for the development of targeted therapeutic strategies.
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Enfermedad Coronaria/sangre , Proteínas del Tejido Nervioso/sangre , Fragmentos de Péptidos/sangre , Enfermedad Aguda , Anciano , Biomarcadores , Enfermedad Coronaria/complicaciones , Enfermedad Coronaria/mortalidad , Electrocardiografía , Femenino , Insuficiencia Cardíaca/clasificación , Insuficiencia Cardíaca/epidemiología , Insuficiencia Cardíaca/etiología , Mortalidad Hospitalaria , Humanos , Tablas de Vida , Masculino , Persona de Mediana Edad , Péptido Natriurético Encefálico , Oportunidad Relativa , Valor Predictivo de las Pruebas , Pronóstico , Curva ROC , Riesgo , Medición de Riesgo , Factores de Riesgo , Resultado del Tratamiento , Troponina T/sangreRESUMEN
The in vivo assessment of free radicals concentration is hampered by their instability and extremely short half-life. The Diacron Reactive Oxygen Metabolites (D-ROM) test is a recently introduced method to evaluate the peroxidation of organic compounds. Since the manual performance of the test provides excessive analytical imprecision, the aim of this study was to evaluate the automation of this test. Within- and between-run imprecision and interference were assessed according to the guidelines proposed by the NCCLS. The reactive oxygen metabolites' (ROM) stability was evaluated in different physical conditions. For within-run and between-run imprecision the coefficients of variation were consistently lower than 5%. The maximum allowable concentration was 28.2 mmol/l, 0.068 mmol/l and 171 mmol/l for triglycerides, haemoglobin and bilirubin, respectively. Serum storage at -20 degrees C provided adequate ROM stability for up to 3 months, whereas storage at 4 degrees C yielded non-reproducible results. In conclusion, our data provide evidence that the D-ROM assay has both an acceptable stability and an adequate imprecision. The automated assay may be regarded as a fast and reproducible method for the quantitative evaluation of oxidative stress. Since it is easily performed, the method is suitable for routine in clinical laboratories and may provide an accurate estimation of oxidative stress in vivo.