Evaluation of iQ200 Automated Urine Microscopy Analyzer / 대한진단검사의학회지

BACKGROUND: Microscopic examination of urine sediment is one of the most commonly performed tests in the clinical laboratory. However, manual microscopic sediment examination is labor-intensive, time-consuming and imprecise. In this study, we evaluated the analytical performance and clinical usefulness of a recently introduced image-based automated urinalysis system, Iris iQ200 (Iris Diagnostics, USA). METHODS: We assessed the iQ200 for linearity, precision and carryover rate using patient's samples and quality control materials. On 337 urine samples, urine sediment analyses performed by the iQ200 were compared with manual microscopy results. RESULTS: The iQ200 showed a good linearity (r2>0.99) for all cellular components analyzed. Within-run and total CVs on urine specimens and quality control samples were less than 10% except for within-run CV for the samples with low concentration of the squamous epithelial cells. The carryover rates were 0.21% for RBCs and 1.92% for WBCs. The agreement rates within one grade between the iQ200 and manual microscopy for RBCs, WBCs, and squamous epithelial cells were 93.8%, 94.2% and 96.9%, respectively. CONCLUSIONS: Since the iQ200 showed a reliable analytical performance and good concordance with manual microscopy, it could be useful in the clinical practice as a screening procedure.

Analysis and Countermeasures of False Determination of the Results in Urine Particles with IQ200 Automated Urinalysis Analyzer / 医疗卫生装备

Objective To discuss the factors that affect the examination of urine formed elements by IQ200 automated uri-nalysis analyzer causing false positive and look for the solution methods. Methods 2,319 urine samples were tested by IQ200 automated urinalysis analyzer and microscopy. The results were contrasted and the false positive reasons were ana-lyzed. Results When using IQ200 automated urinalysis analyzer,the false positive rate of red cell is 14.7%. Crystals,bac-teria,yeast like fungus sometimes are regarded as red cell by analyzer. The false positive rate of white cell is 15.75%. Small round cells,lots of bacterium can cause false positive; the false positive rate of cast is 38.58 % and viscose rayon is main agent. Conclusion Many factors can affect the examination in IQ200 automated urinalysis analyzer and cause false positive,so IQ200 can only be used for scanning,which is very important to observe sediments by microscopic examination when pathologic ingredients in urine are increased and at the same time all above interferences are positive and manifold.