AIM: To validate whether quantitative flow-cytometric analysis of particulate matter in urine would allow for accurate and rapid enumeration of red blood cells (RBC), leukocytes (WBC), squamous epithelial cells (EC), casts, and bacteria, a Sysmex UF-100 analyzer was tested in a multicenter study. MATERIAL AND METHODS: At first, reference values were established and found to be < 14 for RBC, < 16 for WBC, < 9 for EC, < 2 for casts and < 173 for bacteria, respectively (counts per microl; 97.5 percentile). Due to the wide use of dipstick and microscopic sediment analysis in routine urine diagnostics, comparative studies on 950 random urine samples were performed. Bacterial counting combined with WBC enumeration was further compared in 266 routine urinary microbiologic cultures. RESULTS: Good correlations were found comparing UF-100 results of RBC (r = 0.89), WBC (r = 0.94), and EC (r = 0.74) with Fuchs-Rosenthal Chamber (FRC) counts. However, some misclassification of casts (r = 0.32) could be observed. Correlations of UF-100 with dipstick and sediment testing was significant (p < 0.001), but the scatter of the latter two methods is too wide to consider them as quantitative methods. Promising results further revealed that the analyzer has a good negative predictive value (NPV) for microbiologically negative cultures, especially for cultures with bacterial counts of 10(5)/l (NPV = 95%). CONCLUSION: The analyzer is capable of providing rapid and reliable urine analysis of cellular particles avoiding the known imprecision of dipstick and sediment methodology. Thus, when used in an algorithm, combined with dipstick or quantitative urine chemistry analysis (for hemoglobin, esterase, protein, glucose, etc.), this analyzer might serve as a rapid and accurate screening tool in routine urine analysis, thereby reducing manual reviewing rate as well as the number of missed samples, compared to screening with dipstick alone.
AIM: To validate whether quantitative flow-cytometric analysis of particulate matter in urine would allow for accurate and rapid enumeration of red blood cells (RBC), leukocytes (WBC), squamous epithelial cells (EC), casts, and bacteria, a Sysmex UF-100 analyzer was tested in a multicenter study. MATERIAL AND METHODS: At first, reference values were established and found to be < 14 for RBC, < 16 for WBC, < 9 for EC, < 2 for casts and < 173 for bacteria, respectively (counts per microl; 97.5 percentile). Due to the wide use of dipstick and microscopic sediment analysis in routine urine diagnostics, comparative studies on 950 random urine samples were performed. Bacterial counting combined with WBC enumeration was further compared in 266 routine urinary microbiologic cultures. RESULTS: Good correlations were found comparing UF-100 results of RBC (r = 0.89), WBC (r = 0.94), and EC (r = 0.74) with Fuchs-Rosenthal Chamber (FRC) counts. However, some misclassification of casts (r = 0.32) could be observed. Correlations of UF-100 with dipstick and sediment testing was significant (p < 0.001), but the scatter of the latter two methods is too wide to consider them as quantitative methods. Promising results further revealed that the analyzer has a good negative predictive value (NPV) for microbiologically negative cultures, especially for cultures with bacterial counts of 10(5)/l (NPV = 95%). CONCLUSION: The analyzer is capable of providing rapid and reliable urine analysis of cellular particles avoiding the known imprecision of dipstick and sediment methodology. Thus, when used in an algorithm, combined with dipstick or quantitative urine chemistry analysis (for hemoglobin, esterase, protein, glucose, etc.), this analyzer might serve as a rapid and accurate screening tool in routine urine analysis, thereby reducing manual reviewing rate as well as the number of missed samples, compared to screening with dipstick alone.
Authors: A Litke; R Bossart; K Regez; U Schild; M Guglielmetti; A Conca; P Schäfer; B Reutlinger; B Mueller; W C Albrich Journal: Infection Date: 2013-02-24 Impact factor: 3.553
Authors: Daniel Drozdov; Stefanie Schwarz; Alexander Kutz; Eva Grolimund; Anna Christina Rast; Deborah Steiner; Katharina Regez; Ursula Schild; Merih Guglielmetti; Antoinette Conca; Barbara Reutlinger; Cornelia Ottiger; Florian Buchkremer; Sebastian Haubitz; Claudine Blum; Andreas Huber; Ulrich Buergi; Philipp Schuetz; Andreas Bock; Christoph Andreas Fux; Beat Mueller; Werner Christian Albrich Journal: BMC Med Date: 2015-05-01 Impact factor: 8.775
Authors: Daniel Drozdov; Anja Thomer; Marc Meili; Stefanie Schwarz; Rita Bossart Kouegbe; Katharina Regez; Merih Guglielmetti; Ursula Schild; Antoinette Conca; Petra Schäfer; Barbara Reutlinger; Cornelia Ottiger; Florian Buchkremer; Alexander Litke; Philipp Schuetz; Andreas Huber; Ulrich Bürgi; Christoph A Fux; Andreas Bock; Beat Müller; Werner C Albrich Journal: Trials Date: 2013-03-22 Impact factor: 2.279