Erythrocyte sedimentation rate measurements using MIX-RATE® X20 and VISION A automated analyzers: Method validation and comparison study.

BACKGROUND: The Westergren method for erythrocyte sedimentation rate (ESR) measurement has a few drawbacks such as being a time-consuming process, poses a risk of biohazard exposure and requires high sample volume. Recent alternative methods and analyzers were developed to overcome those limitations. In this study, we validated two automated ESR analyzers, MIX-RATE® X20 and VISION A, and assessed their analytical performance against the Westergren method. METHODS: The analyzers were validated for inter-run and intra-run precision. Hemolysis interference and sensitivity to fibrinogen were also analysed. Analytical performance was performed using 177 patient samples spanning low (<40 mm/h), medium (40-80 mm/h), and high (>80 mm/h) ESR ranges. Method agreement and bias against the Westergren method were calculated. RESULTS: The highest intra-run imprecision was seen in the low ESR range for both analyzers. They showed very high agreement with the Westergren method assessed by Spearmen rank correlation coefficient analysis, r = 1.000, p < .0001 for both analyzers. Bland-Altman analysis yielded overall insignificant mean biases for all comparisons. However, systematic positive and negative bias were observed at medium and high ESR levels analysed by MIX-RATE® X20 while negative bias was evidenced in the high ESR level measured by VISION A. CONCLUSIONS: Overall, results from both automated ESR analyzers showed comparable analytical performance with the Westergren method especially for low ESR levels. However, both positive and negative systematic bias were documented in the high levels. Thus, for clinical use, it must be assessed whether these biases could affect the cut-off for significant clinical values.

Evaluation of the Diesse Cube 30 touch erythrocyte sedimentation method in comparison with Alifax test 1 and the manual Westergren gold standard method.

The erythrocyte sedimentation rate (ESR) is a traditional nonspecific laboratory test used for the assessment of inflammation. Even if its usefulness is nowadays being largely debated, it is still considered a valuable laboratory test in selected clinical conditions, such as rheumatoid diseases, orthopedic infections and Hodgkin's lymphoma, and it can be used for the infectious, inflammatory, malignancies, and autoimmune diseases follow-up. The introduction of new methodologies on semi-automated and automated analyzers started about four decades ago and opened a new era of ESR analysis characterized by shorter assay time, use of (EDTA) undiluted blood, that increases sample stability and allows using a single sample for also other hematologic tests, and greater safety for laboratory personnel. In this context, the aim of this study was to evaluate the performances of new device Diesse Cube 30 touch, comparing it with Alifax Test 1 and with the gold standard Westergren method. The new Diesse Cube 30 touch for determination of the ESR shows a good correlation with the manual Westergren gold standard method in a shorter time, and in a standardized way, since all the phases of the test are automatized. The Diesse Cube 30 touch respect the manual gold standard method, displayed a small bias to confirm that the new automated test system tended to have a small bias for ESR values (mean positive bias +0.2 mm/h). The findings of the present study show that the Diesse Cube 30 touch Westergren-based method can be a valid alternative in laboratory analysis for the determination of ESR.

[Description and assessment of a rapid new method for measuring erythrocyte sedimentation rate]. / Beschreibung und Prüfung einer neuartigen schnellen Methode zur Messung der Blutkörperchensenkungsgeschwindigkeit.

A new method for the rapid photometric determination of the erythrocyte sedimentation rate (ESR) is described and compared with the Westergren technique. The basis of this method is the development of a new physical equation valid for transport processes, in which sedimentation processes can be described by means of a linear regression analysis. After the mathematical transformation, the measured ESR data follow a linear function. The apparatus evaluated measures within a few minutes the velocity profile of the ESR over a distance of about 2 X 10(-4) meter by kinetic determination of the optical density of a short blood column filled in a small cuvette. A microprocessor calculates the linear regression and derives the one and two hour values by extrapolation. The correlation of this method with the standard Westergren technique, determined over 20 days is acceptable (R = 0.95; n = 368). The reproducibility of the same sample (n = 20) is better than that of the conventional procedure. The reproducibility determined with different instruments (n = 20) is comparable to the precision of the Westergren method. The practical value of this new time- and blood-saving, well standardized method for an efficient patient-care is discussed.