An Evaluation of the Automated Cobas u 701 Microscopy Analyzer for the Routine Screening of Urine to Identify Negative Samples.
Urinalysis based on microbiological culture and manual microscopy requires expertise and is labor intensive. Automated screening could save time and improve patient management in clinical settings. We evaluated the fully automated cobas u 701 analyzer for identifying infection-negative urine samples using 2,046 anonymized samples from a routine pathology laboratory. Samples containing ≥ 40 white blood cells (WBC)/µL and/or ≥ 100 bacteria/µL were considered positive. For microbiological cultures: pure growth of ≥ 108 colony-forming units (cfu)/L was considered significant; > 107 cfu/L was considered significant for pregnant women, children < 12 years, immune-compromised/critical care patients or patients with > 100 WBC/µL. The cobas u 701 analyzer identified 1,346 positive samples, giving a 65.7% culture rate. Sensitivity and negative predictive value were high (> 99%). Most replicates were within two standard deviations of the original measurement. The cobas u 701 analyzer is an effective screening tool for routine urinalysis and demonstrates rapid turnaround times, thus benefiting patients and clinicians.