Urine particle evaluation: a comparison between the UF-1000i and quantitative microscopy

Service of Laboratory Medicine, Department of Clinical Pathology, Ospedale Civile, Monselice, Padua, Italy.
Clinical Chemistry and Laboratory Medicine (Impact Factor: 2.96). 08/2010; 48(8):1107-11. DOI: 10.1515/CCLM.2010.233
Source: PubMed

ABSTRACT The study of urine particles plays a key role in the diagnosis of kidney diseases. In this study, the authors evaluated the correlation between the UF-1000i and quantitative manual microscopy.
A total of 214 untreated urine samples were studied using the Sysmex UF-1000i and compared with results obtained from quantitative manual microscopy using the Fuchs-Rosenthal counting chamber.
Using Pearson statistics, we observed satisfactory correlation between the UF-1000i and quantitative microscopy: for red blood cells (RBCs) r was 0.98, for white blood cells (WBCs) r was 1.00, for epithelial cells (EC) r was 0.96, and for casts r was 0.69. Using linear regression statistics, we also observed satisfactory correlation between the UF-1000i and quantitative microscopy: for RBCs R(2) was 0.95, for WBCs R(2) was 0.99, for EC R(2) was 0.92, and for casts R(2) was 0.48.
In our experience, automated urine particle analysis performed using the Sysmex UF-1000i analyzer is sufficiently precise and improves the workflow in a routine laboratory. Precision was satisfactory and concordance with the reference method is good for RBC, WBC and EC; for casts microscopic observation is required for flagged samples to discriminate hyaline from pathologic casts.

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