ABSTRACT
INTRODUCTION: The rheumatoid factor (RF) is the most common antibody found in patients with rheumatoid arthritis. It is an inflammatory chronic disease characterized by articular involvement, inflammation of synovial fluid, tissue infiltration by leucocytes and joint destruction, which ultimately determine articular deformities. The rheumatoid factor is found in 70%-80% of the adult population and in 10% of the young population. OBJECTIVE: The aim of this research was to compare immunoturbidimetric and latex agglutination methods for the detection of RF in serum. RESULTS: The immunoturbidimetric method displayed sensitivity (95.2%), specificity (89.4%) and high positive correlation (R² = 0,8077) with the latex agglutination method in positive serum samples. CONCLUSION: The study allowed to demonstrate that both immunoturbidimetric and latex agglutination methods equally discriminate between negative and positive serum samples for RF.
INTRODUÇÃO: O fator reumatoide (FR) é o autoanticorpo mais comum encontrado em pacientes com artrite reumatoide, uma doença crônica inflamatória caracterizada pelo envolvimento articular com inflamação do líquido sinovial, infiltração de tecido por leucócitos e destruição das articulações, que acaba por determinar deformidades articulares. O FR é encontrado em 70%-80% da população adulta e em 10% da população juvenil. OBJETIVO: Comparar os métodos de imunoturbidimetria e aglutinação (prova do látex) para a determinação de FR em soro. RESULTADO: Foi possível observar que o método imunoturbidimétrico apresenta sensibilidade (95,2%), especificidade (89,4%) e correlação positiva elevada (R² = 0,8077) com o método de aglutinação pelo látex em amostras de soro positivas. CONCLUSÃO: O estudo permitiu demonstrar que o método imunoturbidimétrico e o método de aglutinação pelo látex são igualmente capazes de discriminar amostras negativas e positivas para FR.
Subject(s)
Humans , Rheumatoid Factor/analysis , Nephelometry and Turbidimetry/methods , Sensitivity and Specificity , Latex Fixation Tests/methodsABSTRACT
BACKGROUND: Measurement of HbA1c levels is widely used to diagnose diabetes mellitus and to evaluate and monitor plasma-glucose concentrations over 6-8 weeks. In this study, we evaluated the diagnostic performance of the newly developed latex immunoturbidimetric method by using Autolab HbA1c. METHODS: We analyzed and compared the diagnostic performance of Autolab HbA1c with that of Toshiba 200FR between April 2009 and July 2009. According to guidelines (EP5-A2, EP6-P, EP9-A2) of the clinical and laboratory standards institute (CLSI), we compared linearity, precision and correlation of Autolab HbA1c with those of G7 (Tosoh Corp., Kyoto, Japan) by using high-performance liquid chromatography (HPLC) method. RESULTS: Data obtained using Autolab HbA1c showed good linearity in mixtures of samples with low (3.1%) and high (15.1%) levels of HbA1c (r2 = 0.9997). In the analysis of within-run precision of the samples with HbA1c levels of 5.1% and 12.1%, the SDs were 0.04 and 0.06 and covariances of these samples were 0.8% and 0.5%, respectively. In the Deming regression model, the regression equation was as follows: Autolab HbA1c = 1.0859xTosoh HPLC-0.6957. CONCLUSIONS: In this study, Autolab HbA1c method showed better performance characteristics than Tosoh G7 did. In reference review, there was no interference of variant hemoglobin. The data acquisition time of Autolab HbA1c was lower than that of Tosoh G7. The advantages of Autolab HbA1c are that it can be used as an autoanlyzer in routine chemical analysis, it does not require pre-analytical treatment, and the samples are automatically treated with distilled water for hemolysis.
Subject(s)
Chromatography, High Pressure Liquid , Chromatography, Liquid , Diabetes Mellitus , Hemoglobins , Hemolysis , Latex , Organothiophosphorus Compounds , WaterABSTRACT
Objective:To approach the significance of serum C-Reactive protein(CRP) and matrix metalloproteinases-9(MMP-9) levels in the diagnosis unstable angina(UA) and its forecasting of prognosis .Methods:The serum CRP levels of 38 cases of UA,36 cases of stable angina(SA) and 35 cases of normal controllers was measured by immunoturbidimetric method.And meanwhile,the serum MMP-9 levels of the above-mentioned three groups was measured by enzyme linked immunosorbent assay(ELISA).Results:When the groups were hospitalized,the CRP levels of the UA group(5.85?2.23 mg/L)was evidently higher than that of the SA group(2.54?1.07 mg/L)and the normal control group(1.21?1.02 mg/L)( P