Comparison of Cobas 6500 and Iris IQ200 fully-automated urine analyzers to manual urine microscopy

Abstract

IntroductionUrine screening is achieved by either automated or manual microscopic analysis. The aim of the study was to compare Cobas 6500 and Iris IQ200 urine analyzers, and manual urine microscopic analysis.Materials and methodsA total of 540 urine samples sent to the laboratory for chemical and sediment analysis were analyzed on Cobas 6500 and Iris IQ200 within 1 hour from sampling. One hundred and fifty three samples were found to have pathological sediment results and were subjected to manual microscopic analysis performed by laboratory staff blinded to the study. Spearman’s and Gamma statistics were used for correlation analyses, and the McNemar test for the comparison of the two automated analyzers.ResultsThe comparison of Cobas u701 to the manual method yielded the following regression equations: y = - 0.12 (95% CI: - 1.09 to 0.67) + 0.78 (95% CI: 0.65 to 0.95) x for WBC and y = 0.06 (95% CI: - 0.09 to 0.25) + 0.66 (95% CI: 0.57 to 0.73) x for RBC. The comparison of IQ200 Elite to manual method the following equations: y = 0.03 (95% CI: - 1.00 to 1.00) + 0.88 (95% CI: 0.66 to 1.00) x for WBC and y = - 0.22 (95% CI: - 0.80 to 0.20) + 0.40 (95% CI: 0.32 to 0.50) x for RBC. IQ200 Elite compared to Cobas u701 yielded the following equations: y = - 0.95 (95% CI: - 2.13 to 0.11) + 1.25 (95% CI: 1.08 to 1.44) x for WBC and y = - 1.20 (95% CI: - 1.80 to -0.30) + 0. 80 (95% CI: 0.55 to 1.00) x for RBC.ConclusionsThe two analyzers showed similar performances and good compatibility to manual microscopy. However, they are still inadequate in the determination of WBC, RBC, and EC in highly-pathological samples. Thus, confirmation by manual microscopic analysis may be useful.

Evaluation of the analytical performances of Cobas 6500 and Sysmex UN series automated urinalysis systems with manual microscopic particle counting

“…Results showed that Sysmex UN series had satisfactory intra- and inter-assay precisions, and no carryover was detected by testing the control materials. The intra- and inter-assay precisions of Cobas 6500 were also reported as satisfactory in our previous report ( 16 ). The diagnostic accuracies of sediment analysis for both systems, compared to manual microscopy, were satisfactory.…”

Preanalytics of urine sediment examination: effect of relative centrifugal force, tube type, volume of sample and supernatant removal

“…Our consultations with the clinical staff at the nephrology department confirmed that higher numbers of those elements are correspondent with clinical presentation of the disease, while the lower numbers do not match the patient condition. Small number of leukocytes and erythrocytes per objective field could be found in urine sediment of healthy patients due to exercise or pregnancy ( 15 , 16 ). Errors in preanalytical phase during urine collection are fairly common and can lead to the contamination of urine sample with erythrocytes or leukocytes ( e.g.…”

“…Nowadays, time consuming manual microscopy is being replaced by fully automated urine analyzers ( 19 , 24 ). These systems are quickly becoming part of routine work in both large and small laboratories as a fast way to exclude urine samples from healthy individuals, increase productivity and reduce inter-observer variability ( 16 , 19 , 24 , 25 ). However, manual examination of urine sediment is still part of routine practice in many European countries.…”

The role of organic urine sediment analysis in the monitoring of renal diseases

“…Urine cytology is useful in the detection and diagnosis of various benign diseases and conditions such as infections of different etiologies, and in distinguishing hematuria from the upper and/or lower urinary tract. In addition, it is useful in detecting inflammation in the bladder and kidney (Caleffi and Lippi, 2005;Bottini et.el., 2005;Bakan et. al., 2016;Alatzas et.al., 2012;Sikirica et.…”

“…Credit for the scientific development in research of urinary corpuscular elements over the past 10 years goes to the automated analyzers or automated microscopy, or more specifically, to the flow cytometry and digital imaging systems (Anderlini et al, 2015;Bakan et al, 2016;Bogaert et al, 2016;Oyaert, and Delanghe, 2018). However, the total accuracy of these instruments in identifying (erythrocytes, leukocytes, epithelial cells, casts) is questionable.…”