We cultured 1000 urines and tested them with the iQ200 Workstation (Iris Diagnostics, Chatsworth, CA, and Arkray, Edina, MN, USA) for leukocyte esterase and nitrite (LE/N), white blood cells (WBC), all small particles (ASP), bacteria, and yeast. Positive culture grew ≥ 10(4) CFU/mL of 1 or 2 uropathogens. Method A assessed LE/N, WBCs ≥ 6/μL, and bacteria/yeast. Method B assessed WBCs ≥ 6/μL, bacteria/yeast, and ASP ≥ 10,000. Each was compared to culture results, clinician's diagnosis (CD), or expert review (ER). Sensitivities by culture were 88.7% (Method A) and 88.3% (Method B), with negative predictive values (NPVs) of 94.4% and 94.2%, respectively. Sensitivity and NPV increased for comparison to the CD (99.6%) and NPVs of 99.0% and 99.3% compared to ER. ASP did not enhance specificity, sensitivity, or NPV. The iQ200 Workstation performed well by any standard, thus providing a reliable system by which to improve the use of laboratory resources.
Published by Elsevier Inc.