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.