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<-/ ~t I ,":' I( I\~ A1 ". \ __ -'-- Biotechnol. Appl. Biochem. (2009) 53.139-144 www.babonline.org (Printed in Great Britain) doi:IO.I~2/BA200BOI88 139 Comparison of labUMat-with-UriSed and iQ®200 fully automatic urine sediment analysers with manual urine analysis Okhan Kadir Akin*l. Muhittin A. Serdarj-. Zeynep Cizmecit. Suleyman Aydin§ Ozlem Genct and *Kecioren Research and Training Hospital, Clinical Chemistry and Laboratory Science, Ankara 063BO, Turkey, tGulhane School of Medicine, Department of Clinical Chemistry, Ankara, 0601B, Turkey, tKecioren Research and Training Hospital, Microbiology and Clinical Microbiology, Ankara 063 BD, Turkey, and §Departrnent of Biochemistry and Clinical Biochemistry, Firat University, School of Medicine, Fira!, Elazig 23 I 19, Turkey Urine analysis is one of the most common tests for assessing urinary-tract and kidney diseases. In recent years there have been new developments in the automation of this test. The objective of the present study was to compare the performances of two urine sediment analysers, namely labUMat with UriSed (77 Elektronika Kft, Budapest, Hungary) and iQ@200 (Iris Diagnostics, Chatsworth, CA, U.S.A.), with the KOVA® method for manual urine measurement by evaluating the results in terms of similar parameters (cells or particles per lower-power field or high· power field). The results obtained using the UriSed and iQ@200 analysers were more reproducible (7.1-30.2 and 14.9-35.4% respectively) than those obtained using the manual technique (17.9-44.4%). Significant correlations were established among the three techniques in the evaluation of leucocytes, erythrocytes and epithelial cells. Although the UriSed, iQ®200 and visual.microscopic measurements were in agreement, confirmation of the results from automated methods by manual urine analyses is significantly useful, especially for pathological cases that were close to the limits of the techniques. Introduction Chemical testing of urine samples (reagent strip methods) and identification and counting of particles have been performed routinely to identify and monitor diseases of the kidney and urinary tract [I]. Despite the introduction of an automated system to count particles more than two decades ago, manual microscopic examination of urinary sediment is still needed. owing to the limitations of this system [2-5]. Owing to such a need. the earliest sediment analysers utilized an image-based analysis system [5-7]. However, even though such automated systems increase the speed of throughput and the precision of measurement, the operator must still inspect images of cells and casts visually as the sam- pie is processed by instruments. This severely limits the usefulness of such systems in terms of freeing technician time for other laboratory tasks. The objective of the present study was to compare the iQ®200 microscopic analyser (Iris Diagnostics, Chatsworth, CA, USA.), which has been in use for some years, with the recently installed Uri5ed automation system [LabUMat (77 Elektronika Kft, Budapest, Hungary)] and with manual urine microscopy, using similar parameters [cells or particles per LPF (Iower.power field) or HPF (high-power field)] for evaluation. Materials and methods We studied 600 recently collected midstream urine samples submitted to our laboratory for diagnostic urinalysis. The samples were collected in sterile containers and transferred to test tubes (3 ml for the iQ®200 analyser, 5.5 ml for LabUMat with UriSed and 10 ml for routine manual diagnostic microscopic urinalysis). No preservatives were added. Samples were analysed within I h of arrival. To reduce inter·observer variability, the same technician performed all the microscopic urinalyses with the same microscope by using the KOVA® system (Hycor Biomedical, Garden Grove, CA, USA.). The examined LPF and HPF areas were determined with a measurement scale so that the numbers of cells or particles in a field (usually measured as cells or particles per LPF or HPF) could be correlated. The HPF and lPF results from the iQ®200 and labUMatwith·UriSed devices were included in the present study. In the iQ®200 analyser, urine particles in the sample are imaged in a planar flow cell that orients and constrains Key words: fully automatK urine sediment analYSIs.iQ(!l200 unne analyser. KOVA ~ system, LabUMat with UriSed urine analyser, visual manual Urine sediment analYSIs. AbbreViations used' EC. eprthelial cell, HPF. high-power field: LPF, IO'N-power field: NPV, negative predictive value; PP\/, positIVe predictive value. RBC. red blood cell; WBC. white blood cell. To whom correspondence should be sent (email dr.okhanakHY@gmail.com). ~ 2009 Portland Press Ltd 140 - ------------._---------- O. K. Akin and others particles hydrodynamically within the focal plane of a microscope objective. The iQ®2oo uses APR'" (AutoParticle Recognition), a well-trained neural network, to classify and quantify twelve formed elements. The results can be auto-reported on the basis of user-defined criteria. iQ®200 takes 500 photographs from each urine sample, compares them with standard images, and classifies particles on the basis of tissue, contrast, shape and size from the image. The iQ®200 device classifies the images and presents them to the user, allowing corrections and new definitions to be introduced [8,9]. The LabUMat operates on the basis of microscopic examination of a urine sample in a special disposable cuvette. During the measurement process, the urine sample is transferred to the cuvette and centrifuged. Highresolution complete views of field images are then recorded automatically by a microscope. The Uri5ed device pipettes a 200 I.d urine specimen and creates a preparation of 0.145 mm'; the depth of the native urine in the cuvette becomes 1.1 mm. After centrifuging the preparation for 10 s at 260 g and thereby pelleting the particles, the device analyses a 2.4 J.LIurine sample by scanning 15 field images. These images are then evaluated by a special algorithm. The sample is evaluated by a special neural-network-based imageprocessing algorithm through the use of the so-called multilevel decision method. Each image is recognized in 'real time', while the evaluation procedure is running on the image just after recording. The evaluation takes 3-4 s per image. This recognition software is implemented in UriSed user software, fully developed and improved by 77 Elektronika. The device also counts the particles by comparing the entire image obtained from the areas examined with standard images. It shows the entire field image to the user and also allows corrections and new definitions to be introduced. The iQ®200 analyser conducts the sediment analysis by utilizing flow cytometry. The UriSed analyser, conversely, carries out this analysis by using the microscopic image of the preparation it produces from the urine sample in full automation. When the two devices are compared, the most significant advantage of the iQ® 200 analyser over the UriSed one is that it makes it possible to individually display the sediment images by classifying them [RBCs (red blood cells), WBCs (white blood cells) and casts]. However, the advantage of the UriSed system is that it displays the entire field image, just as is the case when manual microscopy is used. The UriSed device is capable of scanning 15 field images. Displaying the entire field image simultaneously provides an edge in assessing the sample. For the IQ®2oo analyser, the refractometric method (specific-gravity measurement interval 1.000-1.050), and for ------~th~ec;-La=bOMat wlth-OriSed. the dipstick test (LabStrip U I I plus; Analyticon Biotechnologies AG, Lichtenfels, Germany) (specific-gravity measurement interval 1.000-1.030), are ~ 2009 Portland Press Ltd Table I Reference values for WBCs. -- RBCs and ECs Positive Cells Negative few Moderate WBC, (cellslHPF) RBC, (cellslHPF) EC, (cellslLPF) 0-5 0-2 0-2 6-10 3-5 Low 11-20 6-10 Medlum Many 21-50 11-25 High >51 26-50 >51 used to assess the density. Both devices conduct the urine pH analyses through the dipstick test (pH indicator). Liquicheck Control (urinalysis control) by Bio-Rad Laboratories (Hercules, CA, U.S.A.) level I and level 2 was utilized in the reproducibility study (lot numbers: level I, 6 I261; level 2, 61272). In order to analyse reproducibility within or between the runs, the coefficients of variation were estimated on 20 measurements of two different control materials [level I: 0-2 RBCs, 0-1 WBC; level 2: 20-120 RBCs, 10-50 WBCs)]. During the assessment of patient results, the reference values given in Table I were used for WBCs, RBCs and ECs (epithelial cells) [10]. Cases that were viewed as negative and positive by all three techniques were accordingly recorded as negative or positive. When the results of three techniques were not in agreement, they were re-tested on the basis of established cut-off values; checks were performed using strips, and an attempt was made to establish reliable values. When two of the three methods gave positive results, the sample was assumed positive. Sensitivity, specificity, PPV (positive predictive value) and NPV (negative predictive value) were calculated on the basis of this assessment. Specific-gravity values obtained from refractometric analysis by the iQ®200 were utilized to study the effects of specific-gravity and pH in cases that gave inconsistent results. The pH values used were averages of the iQ®200 and UriSed strip pH results. Statistical analyses were performed using SPSS® (version 15.0) for Windows. Lilifor's test was used for first estimates of the population mean and variance based on the data. Non-parametric Gamma statistics were performed to measure correlations and the McNemar test was used to measure changes in distribution of two dichotomous variables. The independent sample t test was used to evaluate the differences in specific-gravity and pH measurements in non-concordant cases. A value of P < 0.05 was considered statistically significant. Results The reproducibility of WBC and RBC counts was assessed at two different levels using all three methods, and the results are shown in Table 2. Comparison of automatic and manual urine analysis Table 2 Reproducibility of iQ(!)200. UriSed and manual methods Abbreviation: 0/. coefficient of variatIon. CellslHPF Bet......-eenprecision Within precision Level I 0/(%) Mean 1.6±0.3 1.2 ± 0.4 19.1 35.4 RBCs WBCs 1.4±0.4 1.2 ± 0.4 RBCs WBCs 1.6±0.7 1.5±0.7 Method Cells Mean Q"'2oo RBCs W8Cs UriSed Manual Table 3 ± S.D. Level 2 Level I ± SD. Level 2 ± SD. ± 5.D. 0/(%) Mean 1.7 ± 0.4 1.2 ± 0.4 23.5 33.3 43.5 ± 7.8 39.6 ± 6.7 17.9 16.9 7.1 13.1 1.5 ±0.5 1.3 ±04 33.3 30.8 44.7 ± 4.5 36.9 ± 5.6 10.1 15.2 17.4 19.2 1.5 ±08 1.6 ± 0.8 53.3 50.0 429±8.1 36.4 ± 7.6 18.9 20.9 0/(%) Mean 42.4 ± 6.3 38.6 ± 6.3 14.9 16.3 28.7 302 45.7 ± 3.2 378 ± 5.0 42.4 44.4 41.4 ± 7.2 35.3 ± 6.8 0/(%) Comparison of iQ<!>200. UriSed and manual WBC countS CellslHPF -- UnSed Q"'2oo Manual (cellslHPF) 0-5 5-10 11-20 21-50 > 51 Total O-S 5-10 11-20 21-50 > 0-5 5-10 11-20 21-50 > 51 Total 466 17 I 0 0 484 8 35 I I 0 45 2 17 16 0 2 J7 J 0 J 6 J 15 0 0 I I 17 19 478 69 22 8 22 600 469 JJ 2 0 0 504 8 32 8 0 I 49 I 4 11 2 0 18 0 0 I 6 9 16 I 0 0 0 12 IJ WBC counts using the manual method and the iQ®200 and UriSed analysers are compared in Table 3. The Gammastatistics value was 0.975. When we analysed the data in relation to clinically positive versus negative results (5 WBCs/HPF). the iQ®200 and manual methods differed significantly (McNemar test; P < 0.00 I). Overall. the nonconcordant results could have affected 5.16 % of all clinical diagnoses (Table 3). 5imilarly. comparison between the UriSed and manual methods for WBC measurements gave Gamma statistics of 0.974. and again there was a significant difference in terms of clinical evaluation (McNemar test; P < 0.00 I). Among all cases. 7.5 % of the results were nonconcordant (Table 3). Finally. the Gamma statistics for the comparison of UriSed and iQ®200 was 0.969. and this rate was established as different in both automated techniques (McNemar test; P < 0.000 I). Analysis of the data in terms of clinically positive and negative results (5 WBCs/HPF) showed non-concordance in 6.66 % of all cases (Table 4). Comparison between the iQ®200 and manual methods in respect of RBC measurement showed a good correlation (Gamma statistics 0.956). but the two methods differed significantly in relation to clinically positive versus negative results (two RBCs/HPF) (McNemar test; Table 4 51 Total 478 69 22 8 22 600 Comparison of UriSed and iQ<!>200 WBC counts Uri5ed (cellslHPF) Q"'2oo 0-5 6-10 11-20 21-50 > 51 Total (cellslHPF) 0-5 6-10 11-20 21-50 > 51 Total 473 22 7 2 0 503 11 21 0 I 14 2 1 18 0 I I 8 6 16 0 0 0 I 12 IJ 483 45 37 15 19 600 IS 2 0 49 P < 0.00 I); clinical non-concordance was 10.2 %, overall (Table 5). Comparison between the UriSed and manual methods showed a similar pattern (Gamma statistics. 0.958; McNemar test P < 0.000 I). with a difference in respect of the clinical results (Table 5). Similar results were also obtained from the comparison between iQ®200 and UriSed in terms of RBC measurement (Gamma statistics. 0.975; McNemar test, P < 0.000 I and non-concordance affecting clinical results in 8.7 % of all cases) (Table 6). Although measurements of EC counts by the three methods correlated. there were differences in 9 % of the cases between manual and iQ®200. 10.5 % of the cases © 2009 Portland Press Ltd 141 142 0. K. Akin and others Table 5 Comparison of iQ~200 and manual RBC counts CellslHPF -UnSed 00"'200 Manual (cellslHPF) G-2 3-5 6-10 11-25 26-50 > G-2 3-5 6-10 11-25 26-50 > 51 Total 430 42 2 2 I 0 477 IJ JI 8 0 0 0 52 I 8 13 I 0 0 ~3 0 5 2 11 I 0 19 0 0 I 5 2 I 9 0 0 0 3 3 14 20 Table 6 Comparison 51 Total G-2 J-5 6-10 11-25 26-50 > 444 86 26 22 7 15 600 439 67 11 2 I 0 519 5 13 7 2 0 0 27 0 6 6 2 0 0 14 0 0 2 12 3 I 18 0 0 0 2 2 I 5 0 0 0 2 I IJ 16 51 444 86 26 22 7 15 600 Table 8 Sensitivity. speciflCity. PPV and NPV results from iQID200. and KOVA~ systems of iQ~200 and UriSed for RBC counts Total UriSed Uri5ed (cellslHPF) 00"'200 (cellslHPF) G-2 3-5 6-10 11-25 26-50 > 51 Total Table 7 Comparison EC counts G-2 3-5 6-10 472 39 7 2 0 0 520 4 12 8 3 0 0 27 0 I 7 4 2 0 14 11-25 I 0 I 8 6 2 18 26-50 > 51 Total 0 0 0 2 I 2 5 0 0 0 0 0 16 16 477 52 23 19 9 20 600 Method Cells Sensitivity SpeciflClty PPV NPV 00"'200 RBC, WBC, 75.8 85.5 96.1 97.4 87.8 90.3 91.5 96.0 Un5ed RBC, WBC, 68.7 759 988 97.6 95.8 902 89.2 93.4 KOVA"' RBC, WBC, 68.0 85.2 97.0 97.2 89.8 89.3 88.6 96.0 00"'200' RBC, WBC, 93.7 936 99.1 99.6 97.6 98.5 97.5 98.1 UriSed' RBC, WBC, 91.7 94.2 99.J 98.5 98.1 94.9 96.8 98.3 among iQ~200. UriSed and manual techniques for Manual (cellslLPF) G-2 Low MedIum High G-5 00"'200 Uri5ed 467 473 15 9 4 4 0 0 Low ,Q"'200 Un5ed 34 48 42 30 9 8 I 0 Medium iQ"'200 UriSed 0 4 5 9 10 9 7 0 'Q"'200 Un5ed I I 0 0 0 2 High • Results obtained when assessed together With strip or KOVA(!l. Table 9 Relationship among non-concordances. WBCs and RBCs Parameter n WBC, RBC, Specific gravity SW 56" 1.017±0.005 1.017±0.006 1.016± 0.007 1.015 ± 0.006 0.987 0.118 P value. pH 518' 82" between manual and UriSed, and 8 % of the cases between iQ®200 and UriSed (Table 7). The sensitivity, specificity, PPY and NPY results obtained using established criteria are given in Table 8. There were no statistically significant differences in the specific gravity and pH measurements among cases by any of the three techniques, irrespective of the concordance among the results (Table 9). Discussion Manual analysis of urine sediment is fraught with methodological problems. Many factors may impair its precision and ~ 2009 Portland Press Ltd specific gravity and pH for P value. 7.77 ± 1.08 7.82 ± 0.89 0.648 7.65 ± 1.02 7.83 ± 0.97 0.123 • Concordant results for wacs or RBCs measured by all three methods. 10 Non-concordant results for WBe or RBC measured by all three methods. accuracy [I I), ranging from centrifugation to the different interpretations of cell or cast in a urine sediment by different technicians [12]. In addition, the process requires approx. 5-10 min of technician time per specimen [13). Therefore there have been attempts to automate the process to improve accuracy and precision and to save technician time. Comparison The iQ®200 and UriSed are two analysers currently used for microscopic evaluation of urine. Since both analysers yield patient results as cells/HPF and cells/LPF, as does the manual test, it should be easy to compare them. The UriSed microscopic analyser is now being used in an automated form by combining it with LabUMat, which measures urine chemistry. The results of the present study show statistically significant correlations among the manual, iQ®200 and UriSed methods. Ben-Ezra et al. [6] found that results from the UF·I 00 automated urine anaiyser correiated with manual counts. Various researchers have shown that the iQ®200 gives results that correlate significantly with manual counts, but, in the results from specimens with fewer cells, the reproducibility and concordance between the two tests cfecreased, and there were statistically significant differences (especially at less than ten cells/HPF) [6,8,9,1416]. This non-concordance was attributed to cell lysis during centrifugation and resuspension or to protein aggregation [6,14]. However, the same researchers showed that the measurements become more concordant when the cell counts in the urine rise. In our study, the level I sample gave quite reproducible results, especially in manual analysis, but the coefficient of variation was < 20 % for pathological specimens. We predicted that non-concordance among the methods stemmed from specific-gravity and pH differences, so we studied the effects of these variables. However, the nonconcordance was not attributable to these two parameters (Table 9) and further studies will be needed to explain it. The results showed non-concordance between the methods sufficient to affect clinical diagnoses, particularly for urine samples with high cell counts close to the limits of the technique (six to ten cells/HPF for WBC, three to five cells/HPF for RBC) (Tables 2-6). Ben-Ezra et al. [6] reported similar results; they found non-concordance in analytical accuracy for WBC and RBC measurements in 5.6-14.2 % of patients. Although other workers have reported similar levels of non-concordance affecting clinical results, that study [6] was the first to present these data [14-16]. Table 8 shows PPVs and NPVs obtained through the evaluation of automated systems and the manual system, either individually or in unison. Thus, when the doubtful results were ev~luated by the manual method and the automated techniques together, PPV and NPV values were observed to have increased. In terms of analytical accuracy, a significantly high number of false negative results were obtained, even though their specificities were adequate (Table 8). As observed in the present study, analytical accuracy was increased if the results were evaluated by strip analysis or if a visual assessment was carried out. We consider that verification of microscopic analyses of urine by manual microscopic and chemical analyses would decrease the number of clinically significant of automatic and manual urine analysis errors, particularly for cases at the limits of the cell or cast techniques [14-16]. In addition, even though microscopic urine analyses are less frequently performed because the use of automated techniques has increased (especially in higher-capacity hospitals), the usefulness of the manual method should be emphasized in educating clinical laboratory staff, bearing in mind that it is still the gold standard. In summary, although the two automated techniques, UriSed and iQ®200, are highly reproducible and are able to analyse large numbers of urine samples quickly and simultaneously, it is important to confirm the results by manual urine analysis, especially for pathological cases at the limits of the techniques, and/or to compare them with urine-strip results. Acknowledgement We thank BioDPC, Istanbul, Turkey (the representatives of Iris Diagnostics in Turkey) and MED-KIM, izmir, Turkey (the representatives of 77 Elektronika Kft in Turkey) for their scientific and technical support during the present study. Funding This work was supported by the Kecioren Research and Training Hospital [educational grant no. 20080200 I]. The funding organization played no role in the design of the study, review and interpretation of the data, nor in the preparation or approval of the manuscript. References 2 3 4 5 6 7 8 Fuller,C. E..Threane, G. A and Henry, J. B. (200 I) In Clinical DiagnosISand Management by Laboratory Methods, 20th edn (Henry, j. B.. ed). pp. 367-402. WB. Saunders. Philadelphia Okada, H.. Sakai, t, Kawabata, G.. Fujisawa,M., Arakawa, 5.. Hamaguchi, Y.and Kamidono, S. (200 I) Am. J. On. Pathol. 115,605-610 Regen~er,A, Haenni, V.. Risch,L.. Kochli,H. P, Colombo, J. P. Frel, R. and Huber, A R. (200 I) On. 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