UriSed 3 and UX-2000 automated urine sediment analyzers vs manual microscopic method: A comparative performance analysis.

BACKGROUND: Fully automated urine analyzers now play an important role in routine urinalysis in most laboratories. The recently introduced UriSed 3 has a new automated digital imaging urine sediment analyzer with a phase contrast feature. The aim of this study was to compare the performance of the UriSed 3 and UX-2000 automated urine sediment analyzers with each other and with the results of the manual microscopic method. METHODS: Two hundred seventy-seven (277) samples of leftover fresh urine from our hospital's central laboratory were evaluated by two automated urine sediment analyzers-UriSed 3 and UX-2000. The results of urine sediment analysis were compared between the two automated analyzers and against the results of the manual microscopic method. RESULTS: Both devices demonstrated excellent agreement for quantitative measurement of red blood cells and white blood cells. UX-2000 had a lower coefficient correlation and demonstrated slightly lower agreement for squamous epithelial cells. Regarding semiquantitative analysis, both machines demonstrated very good concordance, with all applicable rates within one grade difference of the other machine. UriSed 3 had higher sensitivity for small round cells, while UX-2000 showed greater sensitivity for detecting bacteria and hyaline casts. UriSed 3 demonstrated slightly better specificity, especially in the detection of hyaline and pathological casts. CONCLUSIONS: Both instruments had nearly similar performance for red blood cells and white blood cells measurement. UriSed 3 was more reliable for measuring squamous epithelial cells and small round cells, while the UX-2000 was more accurate for detecting bacteria and hyaline casts.

Effect of Depth of Centrifuged Synovial Fluid on Leukocyte Esterase Test for Periprosthetic Joint Infection.

Centrifugation of aspirated synovial fluid before leukocytes esterase (LE) testing for diagnosing periprosthetic joint infection (PJI) may make blood tinged specimens interpretable. We aimed to establish the proper sampling depth of centrifuged specimens for LE testing as one diagnostic criterion and also AS-D chloroacetate esterase (CAE) staining testing as an adjunctive tool. A definite PJI knee joint group and an aseptic primary total knee arthroplasty control group were studied quasi-experimentally (N = 46). At 2,000 g for 15 min, 3 ml of synovial fluid was centrifuged. LE strip testing and median synovial WBC count were performed at 2, 4, and 6 mm depths. CAE staining test characterized LE particles. ROC curve, area under the curve, and significant differences were determined. The proper predictive depth to diagnose PJI was sought by forward stepwise logistic regression. All fresh blood-tinged specimens had uncertain interpretations. Centrifugation increased interpretability (55-100%). ROC curve and area under the curve at 2, 4, and 6 mm depths were 0.822, 0.804, and 0.786, respectively. The cut point of ++ to diagnose PJI was statistically significant (p < 0.05) at all depths. p-values of forward stepwise logistic regression at 2, 4, and 6 mm were 0.001, 0.752, and 0.756, respectively. CAE staining confirmed extracellular LE release by polymorphonuclear neutrophils (PMN). A specimen at <2 mm from the surface of centrifuged synovial fluid at a grading of ++ or more for PJI diagnosis is proper for LE testing. CAE staining testing adjunctively characterizes LE particles and cell morphology. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2545-2550, 2017.

Performance Evaluation and Comparison of the Fully Automated Urinalysis Analyzers UX-2000 and Cobas 6500.

OBJECTIVE: To evaluate and compare the performances of the automated urinalysis devices UX-2000 and Cobas 6500. METHOD: A total of 258 urine specimens were collected from the routine specimen workload. We analyzed all specimens on both automated instruments and recorded the turnaround time from each method. Physical, chemical, and sedimentary urine components were compared between the automated and the manual method for each analyzer. RESULTS: The correlation of urine physical/chemical properties between the 2 instruments was excellent. The Cobas 6500 instrument demonstrated a higher level of agreement for red blood cells (Cobas 6500:R= 0.94; UX-2000:R= 0.78) and white blood cells (Cobas 6500:R= 0.95; UX-2000:R= 0.85). The UX-2000 demonstrated higher sensitivity for small round cells, hyaline casts, pathological casts, and bacteria. The median turnaround time was 1.5 minutes and 8.5 minutes for the Cobas 6500 and UX-2000, respectively. CONCLUSIONS: The 2 devices showed similar performance in technical evaluation; they each reduce workload and increase time saving. However, manual examination by technicians is recommended for pathological specimens.

Optimal criteria for microscopic review of urinalysis following use of automated urine analyzer.

BACKGROUND: The Sysmex UX-2000 is a new, fully automated integrated urine analyzer. This device analyzes all physical and chemical characteristics of urine and sediments in urine on single platform. Because sediment analysis by fluorescent flow cytometry has limited ability to classify some formed elements present in urine (e.g., casts), laboratories should develop criteria for manual microscopic examination of urinalysis following the use of the automated urine analyzer. METHODS: 399 urine samples were collected from routine workload. All samples were analyzed on the automated analyzer and were then compared to the results of the manual microscopic method to establish optimal criteria. Another set of 599 samples was then used to validate the optimized criteria. The efficiency of criteria and review rate were calculated. The false-positive and false-negative cases were enumerated and clarified. RESULTS: We can set 11 rules which are related to the parameters categorized by the UX-2000, including cells, casts, crystals, organisms, sperm, and flags. After optimizing the rules, the review rate was 54.1% and the false-negative rate was 2.8%. CONCLUSIONS: The combination of both UX-2000 and manual microscopic method obtain the best results. The UX-2000 improves efficiency by reducing the time and labor associated with the specimen analysis process.

Should acidification of urine be performed before the analysis of calcium, phosphate and magnesium in the presence of crystals?

BACKGROUND: Acidification of urine has been recommended before testing for calcium, phosphate, and magnesium. We investigated the necessity of pre-analytical acidification in both crystallized and non-crystallized urine samples. METHODS: From 130 urine samples obtained via routine urine analysis, 65 (50%) samples were classified as non-crystallized. All samples were divided into three groups: untreated samples, acidified samples with HCl, and acidified samples after 1h room-temperature incubation. Urine samples were measured for calcium, phosphate, magnesium, and creatinine using Modular P800 and were examined for crystals using light microscopy. RESULTS: In crystallized samples, acidified samples with 1h incubation had significantly higher Ca/Cr, P/Cr, and Mg/Cr than did untreated samples with mean differences of 0.04, 0.03, and 0.01 mg/mg, respectively (P<0.001). In acidified samples that were analyzed immediately, crystallized samples had lower calcium concentrations than those of acidified samples with 1h incubation and a mean difference of 0.21 mg/dl (P = 0.025). None of the sample differences which exceeded the critical difference of urinary Ca, P and Mg was observed. CONCLUSIONS: Acidification of urine should be performed before the measurement of Ca, P, and Mg in the presence of urinary crystals. However, the lack of an acidification process does not result in a clinically significant change.