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INTRODUCTION: The erythrocyte sedimentation rate (ESR) includes three phases, each prone to different interferences. Due to many disadvantages of the reference Westergren method, modified and alternate methods have been introduced. The aim of this study was to compare the modified Westergren method on SRS 100/II analyzer in citrate blood with the alternate method on iSED® analyzer in EDTA sample. Additionally, possible interfering factors and ESR stability during 6 h at room temperature were evaluated. METHODS: A total of 188 samples were included in the method comparison. Additionally, the effects of inflammation, haematocrit and MCV values on ESR were evaluated. To determine ESR stability in different samples, ESR was evaluated at three time points; within 15 min of blood sampling and after 3 and 6 h in different sample types and analyzers (N = 65). RESULTS: Results indicated the constant difference between tested methods with obtained mean bias of 5 mm (95% CI: 3-7). There was higher absolute mean bias in groups with ESR > 40 mm and elevated inflammation markers (p < 0.001). Regarding different MCV and haematocrit groups there was no statistically significant difference in obtained absolute mean biases for MCV (p = 0.087) while there was higher bias in low haematocrit group compared to normal haematocrit (p = 0.004). In addition, there was a significant difference between ESR values at different time points for iSED® (p < 0.001) and no difference for SRS 100/II analyzer (p = 0.406). CONCLUSION: There are differences in ESR values between tested methods. EDTA sample on iSED® should be analysed as soon as possible to avoid falsely increased ESR.
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Recolección de Muestras de Sangre , Inflamación , Humanos , Sedimentación Sanguínea , Ácido Edético , HematócritoRESUMEN
The erythrocyte sedimentation rate (ESR) has been commonly ordered in hematology laboratories and used to screen for monitoring responses to therapy and identifying inflammatory conditions. To overcome the limitations of traditional ESR measurements, various methods have been developed and compared to the established reference method. This study evaluates the analytical performance of ESR fast detector and Improve® ESR analyzer compared to the reference method. Method validation and comparison were performed in 189 volunteer blood samples according to the International Council for Standardization in Hematology recommendations. The analytical efficacy of ESR fast detector and Improve® ESR analyzer was also assessed and compared with the reference method and C-reactive protein (CRP) levels. The results demonstrated that the precision of ESR fast detector and Improve® ESR analyzer was considered as the acceptance criterion for the ESR measurement. The method comparison analysis between the two modified Westergren methods and reference method demonstrated a strong correlation with the Spearman's rank correlation coefficient of 0.94, with a mean difference of -2.1 and -7.7 mm/h in the ESR fast detector and Improve® ESR analyzer, respectively. Analysis of the area under the receiver operating curve illustrated a high analytical performance compared to the reference method and CRP level. The measurement of ESR level using the ESR fast detector and Improve® ESR analyzer is a reliable method and has a high analytical performance, which can be used instead of the reference method for screening inflammatory conditions.
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Hematología , Humanos , Sedimentación Sanguínea , Hematología/métodos , Estándares de Referencia , LaboratoriosRESUMEN
OBJECTIVES: The VES-Matic 5 is an automated analyzer that assesses erythrocyte sedimentation rate based on a modified Westergren sedimentation technique. Instrument performance was established by addressing the recommendations of the International Council for Standardization in Haematology. METHODS: Comparison against the reference Westergren method was performed for all samples, and further for the low, middle, and upper third of the analytical range. Intra-run precision, inter-run precision, and interference studies were further assessed. This study included the evaluation of reference ranges. RESULTS: The comparison of methods by Passing-Bablok analysis has shown a good agreement without systematic or proportional differences. The regression equation was y=-0.646 + 0.979x. The mean bias of -0.542 was obtained by Bland-Altman analysis and the upper limit of 8.03 with the lower limit of -9.11 can be considered clinically acceptable. Intra-run and inter-run precision were good for each parameter and interference studies did not show any significant bias with exception of anemia samples, which showed a proportional difference when comparing high erythrocyte sedimentation rate values. Using the local adult reference population, we verified the reference ranges in comparison to those available in the literature, and according to the Clinical Laboratory Standards Institute (CLSI) EP28-A3C document. We determined the upper limit partitioned by gender and the following age groups: from 18 to 50, from 50 to 70, and over 70. CONCLUSIONS: The VES-Matic 5 analyzer presented good comparability with the reference method. As there are commercial quality control and suitable external quality assessment (EQA) material and programs, the VES-Matic 5 can be employed appropriately for routine purposes.
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Hematología , Adulto , Sedimentación Sanguínea , Hematología/métodos , Humanos , Control de Calidad , Valores de Referencia , Proyectos de InvestigaciónRESUMEN
INTRODUCTION: The erythrocyte sedimentation rate (ESR) is a nonspecific inflammation indicator. In laboratory testing, automated ESR analyzers may use the reference Westergren method (Reference WG), modified Westergren (Modified WG), or Alternate ESR method (Alternate ESR) based on photometric rheology. A prototype hematology analyzer Celltac α+ (Nihon Kohden Corporation) with built-in Novel ESR analysis technology (Novel ESR) was developed to improve the accuracy of Alternate ESR. Alternate ESR uses only the aggregation phase information of Reference WG. The Novel ESR adds sedimentation and packing phase information obtained by hematology analyzer measurands. High correlation with WG was ensured by predicting the ESR value using Hematocrit (Hct) and MCV values as correcting parameters. METHODS: Novel ESR was compared with Modified WG (MONITOR-40, Joko Corporation) and Reference WG, according to internationally recognized guidelines: Precision, carryover, limit of quantification, comparability, linearity, accuracy, and fibrinogen sensitivity. Samples from healthy volunteers and clinical patients were used. The correction performance of Novel ESR and Modified WG was compared with Reference WG by regression analysis in three range categories for ESR and measurands affecting ESR correction (Hct, MCV, and MCH). RESULTS: Novel ESR showed sufficient basic performance and comparability with Modified WG. In the accuracy study comparing with Reference WG, the regression equation was y = 1.026x + 0.5(r = .945,P < .001;n = 271). When evaluating the correction performance, the slopes were within 0.8-1.2, except for the high part of Hct. All intercepts were within 10 mm. CONCLUSION: This study validated the correction performance to the initial estimated ESR value by aggregation phase information using information reflecting sedimentation and packing phase obtained from automated hematology analyzer. The Celltac α+ Novel ESR provided results equivalent to Reference WG.