Clinitek Atlas Research Articles

Evaluation of the Urine Protein/Creatinine Ratio Measured with the Dipsticks Clinitek Atlas PRO 12.

Screening for urine proteins is recommended for the detection of albuminuria in high risk groups. The aim of this study was to compare the Clinitek Atlas PRO12 reagent urine strip with quantitative methods for the determination of protein/creatinine ratio and to evaluate the usefulness of the semi-quantitative Clinitek Atlas PRO12 reagent urine strip as a tool in the early detection of albuminuria among the general population. Six hundred first morning urine specimens were collected from outpatients with various clinical conditions. The results showed that the test data for the urine dipstick Clinitek Atlas PRO12 show good agreement with the quantitative measurement of protein, creatinine and protein/creatinine ratio. In addition, this study shows that 97.2% of the samples which gave "normal" protein/creatinine ratios by the semi-quantitative method, showed albumin/creatinine ratio < 30 mg/g by the quantitative methods. Our results show that Clinitek Atlas PRO12 reagent strips can be used for the purposes of albuminuria screening in the general population.

Avaliação da interferência do ácido ascórbico na detecção da glicosúria

INTRODUÇÃO: O ácido ascórbico (vitamina C) é comumente ingerido como suplemento vitamínico. É uma vitamina hidrossolúvel, excretada pela urina e pode interferir nos ensaios laboratoriais, como nas reações de oxirredução para detecção da glicosúria. OBJETIVO: Este trabalho tem como objetivo avaliar a interferência do ácido ascórbico na detecção de glicosúria pelo método de química seca por meio do uso de tiras reagentes. MATERIAIS E MÉTODOS: Amostras de urina foram avaliadas no analisador da marca Clinitek Atlas (Siemens Healthcare Diagnostics Inc., EUA). Foram selecionadas quatro amostras de urina com diferentes concentrações de glicose: 100 mg/dl, 250 mg/dl, 500 mg/dl e 1.000 mg/dl. Para cada concentração de glicose foram criadas cinco alíquotas, adicionando-se uma solução de ácido ascórbico 200 mg/dl, suficiente para obter uma concentração final de ácido ascórbico de 20 mg/dl no primeiro tubo, de 50 mg/dl no segundo tubo, de 270 mg/dl no terceiro tubo, de 1.000 mg/dl no quarto tubo e de 2.000 mg/dl no quinto tubo. Após essa adição, as amostras foram novamente avaliadas no analisador Clinitek Atlas. RESULTADOS: Nas amostras com concentração de 20 mg/dl de ácido, não se evidenciou interferência. Nas concentrações iguais e acima de 50 mg/dl, a interferência do ácido ascórbico se fez presente, sendo que o fato foi caracterizado pelos resultados falso negativos para detecção da glicose urinária. CONCLUSÃO: Os resultados demonstraram a interferência do ácido ascórbico no método da química seca (tiras reagentes), subestimando o nível de glicose urinária.

An 83-Year-Old Woman with Discordant Urine Protein Results

An 83-year-old woman presented to the emergency department with weakness and weight loss. A urinalysis was ordered. The urine was clear and light yellow. A urine protein estimate obtained with reagent strips (Clinitek Atlas®; Siemens) was 30 mg/dL; however, quantitative measurement of the total protein concentration (UniCel® DxC 800; Beckman Coulter) of a second urine sample yielded a value of 980 mg/dL. Using reagent strips (Multistix® 10 SG; Siemens) on the second sample again yielded a urine protein estimate of 30 mg/dL. 1. What are the differences between semiquantitative …

Evaluation of the iChem® Velocity™ Urine Chemistry Analyzer in a hospital routine laboratory

The novel urine chemistry analyzer iChem Velocity (IRIS Diagnostics) offers improved urinalysis automation options through integration with the well-established iQ200 urine microscopy analyzer. In the course of optimizing the workflow in our hospital routine laboratory, we evaluated the performance of the iChem Velocity. A total of 257 random urine samples were analyzed with the iChem Velocity, iQ200, Clinitek Atlas (Siemens Healthcare Diagnostics) and by manual microscopy. Depending on the parameter, 93% (hemoglobin) to 100% (urobilinogen), the iChem Velocity and Clinitek Atlas results agreed within the same rank or within one level of difference. The Clinitek Atlas featured a higher sensitivity for hemoglobin (area under the curve 0.86) and leukocyte esterase (area under the curve 0.85) compared with the iChem Velocity (area under the curve for hemoglobin 0.73, leukocytes 0.78). Imprecision was highest for hemoglobin and leukocytes in a pathological sample pool. While the precision of the Clinitek Atlas for hemoglobin measurements was superior, the iChem Velocity was more precise in analyzing protein and pH. Through urinalysis automation with the iChem Velocity and iQ200, we achieved a reduction of hands-on time by 89%. The sensitivity of this new system should be further improved through ongoing development.

Urine particles analysis: Performance evaluation of Sysmex UF-1000i and comparison among urine flow cytometer, dipstick, and visual microscopic examination

Introduction. Our objective was to evaluate a newly invented urine flow cytometer, and select an optimal strategy for urinalysis in clinical practice. Methods. The performance of UF-1000i was evaluated in both control material and patient samples. A total of 1631 specimens were collected and analysed by visual microscopy examination (VME), UF-1000i flow cytometer (Sysmex Medical Electronics Co, Kobe, Japan) and an automated dipstick reflectometer Clinitek Atlas (Bayer Corp, Elkhart, USA). Results. UF-1000i showed good imprecision performance for the main parameters in urine particles with CV values less than 20%. The results from UF-1000i correlated well with VME for erythrocytes (r = 0.96), leukocytes (r = 0.98), and epithelial cell (r = 0.84). The area under the receiver operating curve (AUC) was 0.879, 0.903, 0.783, and 0.817 respectively for erythrocytes, leukocytes, bacteria and CAST in UF-1000i. While in Clinitek Atlas, the AUC was 0.848, 0.803, 0.761, and 0.754 respectively. Sensitivity of combination of the two methods for screening remained at 98% as compared to VME alone, while reducing the visual review rate down to 40%. Conclusion. UF-1000i is capable of reproducible measurement of urine particles in the clinically relevant range and shows its advantage over Atlas. Combination of the two methods is an optimal strategy for urine sample screening.

Comparison of three automated urinalysis systems—Bayer Clinitek Atlas, Roche Urisys 2400 and Arkray Aution Max for testing urine chemistry and detection of bacteriuria

BackgroundOur study is aimed to determine the performance of 3 automated urinalysis systems—Clinitek Atlas, Urisys 2400 and Aution Max. MethodsOne thousand urine specimens were analyzed with the 3 automated systems. The results of the 3 assays were compared for testing urine chemistry and evaluating the capacity of leukocyte esterase and nitrite to detect bacteriuria. ResultsThe correlation between the 3 instruments represented as within 1 grading difference was better between the Atlas and Aution Max systems for pH, blood, glucose, urobilinogen, ketone and specific gravity. For protein and nitrite, better correlation was observed between the Atlas and Urisys 2400, while the Aution Max and Urisys 2400 conveyed better correlation for bilirubin and white blood cells. The sensitivity and specificity of both the leukocyte esterase and nitrite in screening for significant bacteriuria were 71.7, 58.9, 70.8% and 99.1, 99.1 and 97.2%, for the Clinitek Atlas, Aution Max and Urisys 2400, respectively. ConclusionsThe automated urinalysis systems demonstrate acceptable correlations with each other in urine chemistries, especially between the Clinitek Atlas and Aution Max systems on the majority of items. The specificity and negative predictive value of leukocyte esterase and nitrite of the 3 instruments for screening of significant bacteriuria were sufficient to avoid unnecessary urine culture.

Evaluation of an automated urinalysis system for testing urine chemistry, microscopy and culture

This study was designed to evaluate the performance of an automated urinalysis system that utilised three commercially available instruments, the Clinitek Atlas, Sysmex UF-100 and the Alifax Uro-Quick. The results of the automated system for 818 urine samples were compared with the results of manual processing which consisted of phase contrast microscopy, manual dipstick chemistry analysis and culture onto solid media. The correlation between the two methods for urine chemistry was excellent with a concordance of 89, 97, 100 and 98% for pH, blood, glucose and protein, respectively. The quantification of red blood cells and white blood cells had an R2 of 0.855 and 0.92, respectively. A difference scatter plot indicated a trend towards the manual cell count being greater than the UF-100 count as both the red and white blood cell count increased. There was 98% agreement between the automated process and manual culture. The automated urinalysis system is fully integrated and allows for the cross-checking of urine chemistry and microscopy as well as electronic transfer of data. The automated process was used as a screening procedure and some manual testing was necessary. Automation of urinalysis offers a reduction in variation and has comparable results to manual testing.

Routine Workflow for Use of Urine Strips and Urine Flow Cytometer UF-100 in the Hospital Laboratory,1

None of the methods currently available for evaluating hematuria and leukocyturia is perfect. Urinalysis by test strip combined with automated particle counting is an attractive approach that may identify false-negative results of both techniques. We wished to evaluate the possibility that microscopic evaluation of urine samples could be substantially reduced by this approach. The fully automated urine flow cytometer UF-100 classifies urinary particles on the basis of their light scattering, fluorescence, and impedance properties. The instrument counts erythrocytes, leukocytes, bacteria, epithelial cells, and casts and flags the presence of pathological casts, small round cells (SRCs), yeast-like cells, crystals, and spermatozoa. The instrument is intended to replace, to an extent, routine urine microscopy. The operating principles of the UF-100 (1); its precision, accuracy, and analytical sensitivity (2); and its potential for differentiation between renal and postrenal hematuria (3) have been published previously (4). The precision of particle counting in microscope chambers is poorer than counting by flow cytometry (5). The analysis of urine samples by UF-100 and the test strip analyzer Clinitek Atlas showed discordant results in a small but not negligible number of cases. This result has also been described by Ben-Ezra et al. (4). We therefore rechecked the false results in erythrocyte and leukocyte counts by examining discrepant results from both instruments by microscopic evaluation and evaluated a workflow for the routine urine analysis using the combination of UF-100 and Clinitek Atlas. We analyzed 288 mainly pathological urine specimens by both test strip analyzer (Clinitek Atlas; Bayer Diagnostics) and UF-100 (Sysmex). The samples were examined within 3 h of arriving at the laboratory; no preservatives were used. We additionally reviewed 261 by microscopy. The ranking system …

Evaluation of an automated urine chemistry reagent‐strip analyzer

We evaluated the Miles Inc., Clinitek Atlas Automated Urine Chemistry Analyzer for 11 tests: bilirubin, color, glucose, ketones, leukocyte esterase, nitrite, occult blood, pH, protein, specific gravity, and urobilinogen. The instrument uses a roll of reagent strips affixed to a clear plastic support; urine specimens are automatically pipetted onto these strips. The instrument measures the pads' color using reflectance colorimetry. Specific gravity is measured using a fiberoptic refractive index method. Four hospitals participated in the evaluation, and tests were performed only on fresh urine samples. We found the instrument easy to use; it has walk-away capability with up to 40-specimen loading capacity plus spaces for STATs, calibrators and controls. We found good comparability with chemical tests and other nonreagent strip procedures, as well as good agreement with the Miles Inc. Clinitek 200+ urine chemistry analyzer and visual reading of the Miles Inc. Multistix Reagent Strips. The Clinitek Atlas is rugged and reliable, and is suitable for a high-volume urinalysis laboratory.