ABSTRACT
BACKGROUND: The automated urine cell analyzer UF-100 (Syxmex co., Japan), flow cytometer-based instrument, has enabled to perform rapid and efficient work. We evaluated the UF-100 by comparing performance in urine sediment testing with counting chamber, standardized method, and traditional manual microscopy widely used in laboratories, and established reference ranges in our hospital. METHODS: Urine samples were obtained from patients in their 20s to 60s who visited hospital for regular check-up between March and April 2007 at Ewha Womans University Mokdong Hospital. We selected randomly a total of 261 samples (male 130, female 131) and evaluated correlations of red blood cell (RBC) and white blood cell (WBC) counts of UF-100 with counting chamber, and manual microscopy. Moreover, we established reference ranges of UF-100 and counting chamber according to CLSI guideline, using 156 urine samples (male 93, female 63) with normal dipstick (strip) test results. RESULTS: The RBC correlation coefficients between UF-100 and counting chamber, UF-100 and manual microscopy, counting chamber and manual microscopy were 0.538, 0.873, and 0.619, respectively. The WBC correlation coefficients between UF-100 and counting chamber, UF-100 and manual microscopy, counting chamber and manual microscopy were 0.992, 0.902, and 0.893, respectively and showed good correlations. The results of UF-100 were higher than counting chamber and manual microscopy. The RBC reference ranges of UF-100 nd counting chamber were 0.5-24.9/microliter (male 0.4-12.2/microliter, female 0.9-38.8/microliter) and 0-4/microliter (male 0-4/microliter, female 0-5/microliter), and the WBC reference ranges of those were 0.9-21.8/microliter (male 0.8-12.6/microliter, female 2.0-23.4/microliter) and 0-7/microliter (male 0-7/microliter, female 0-9/microliter). CONCLUSIONS: The fully automated analyzer UF-100 could be useful to enhance efficiency by labor-saving, turnaround time reduction and improving throughput and to enable standardization. But it is needed for further study including clinical evaluation, because the results and reference ranges between UF-100 and counting chamber or manual microscopy showed considerable differences.
Subject(s)
Female , Humans , Erythrocytes , Leukocytes , Microscopy , Reference ValuesABSTRACT
BACKGROUND: The automated urine cell analyzer UF-100 (Syxmex co., Japan), flow cytometer-based instrument, has enabled to perform rapid and efficient work. We evaluated the UF-100 by comparing performance in urine sediment testing with counting chamber, standardized method, and traditional manual microscopy widely used in laboratories, and established reference ranges in our hospital. METHODS: Urine samples were obtained from patients in their 20s to 60s who visited hospital for regular check-up between March and April 2007 at Ewha Womans University Mokdong Hospital. We selected randomly a total of 261 samples (male 130, female 131) and evaluated correlations of red blood cell (RBC) and white blood cell (WBC) counts of UF-100 with counting chamber, and manual microscopy. Moreover, we established reference ranges of UF-100 and counting chamber according to CLSI guideline, using 156 urine samples (male 93, female 63) with normal dipstick (strip) test results. RESULTS: The RBC correlation coefficients between UF-100 and counting chamber, UF-100 and manual microscopy, counting chamber and manual microscopy were 0.538, 0.873, and 0.619, respectively. The WBC correlation coefficients between UF-100 and counting chamber, UF-100 and manual microscopy, counting chamber and manual microscopy were 0.992, 0.902, and 0.893, respectively and showed good correlations. The results of UF-100 were higher than counting chamber and manual microscopy. The RBC reference ranges of UF-100 nd counting chamber were 0.5-24.9/microliter (male 0.4-12.2/microliter, female 0.9-38.8/microliter) and 0-4/microliter (male 0-4/microliter, female 0-5/microliter), and the WBC reference ranges of those were 0.9-21.8/microliter (male 0.8-12.6/microliter, female 2.0-23.4/microliter) and 0-7/microliter (male 0-7/microliter, female 0-9/microliter). CONCLUSIONS: The fully automated analyzer UF-100 could be useful to enhance efficiency by labor-saving, turnaround time reduction and improving throughput and to enable standardization. But it is needed for further study including clinical evaluation, because the results and reference ranges between UF-100 and counting chamber or manual microscopy showed considerable differences.
Subject(s)
Female , Humans , Erythrocytes , Leukocytes , Microscopy , Reference ValuesABSTRACT
BACKGROUND: The counting of erythrocyte and leukocyte in cerebrospinal fluid (CSF) is still performed microscopically, using a chamber in most laboratories. However, it is imprecise, has wide inter-observer variability, and is labor-intensive and time-consuming. This study was aimed to examine the possibility of using Sysmex UF-100 flow cytometry (Toa Medical Electronics, Japan) as a means of counting cells in CSF samples. METHODS: From May to September 2006, we obtained 115 routinely collected CSF samples from 90 patients. We compared the performance of the automated method of the UF-100 with the manual counting method using Neubauer chamber. RESULTS: Accuracy statistics for erythrocyte and leukocyte showed a high correlation between the UF-100 and the manual counting method, with correlation coefficients of r2=0.95 and 0.89, respectively. Linearity results demonstrated that the UF-100 method provides accurate results throughout the reportable ranges of erythrocyte and leukocytes. A high degree of inter-assay precision for the UF-100 method was seen. Five cases with high lymphocytes percentage showed falsely low value of leukocyte counts. CONCLUSIONS: The flow cytometric analysis of CSF with the UF-100 offered a rapid and reliable erythrocyte and leukocyte count. UF-100 is expected to be useful for screening method in CSF cell counting. But the manual counting method is still needed for the samples with high leukocyte count or contaminated with peripheral bloods.
Subject(s)
Humans , Cell Count , Cerebrospinal Fluid , Electronics, Medical , Erythrocytes , Flow Cytometry , Leukocyte Count , Leukocytes , Lymphocytes , Mass Screening , Observer VariationABSTRACT
OBJECTIVE To investigate the value of screening hospital urinary tract infection with UF-100 automated urine analyzer. METHODS It was to count the bacteria and white blood cells in 422 urine specimens with UF-100 as well as to culture the specimens quantitatively.Then the sensitivity and specificity of UF-100 counts and the correspondence of the two methods were evaluated with Yerushalmy mode. RESULTS Compared with the culture results,UF-100 showed a sensitivity of 81.5%,specificity of 63.9%,positive predictive value of 29.1%,negative predictive value of 95.0%,false positive rate of 30.5%,false negative rate of 2.8% and an accuracy of 67.2%. CONCLUSIONS The UF-100 is excellent in analyzing urine specimens,and its bacteria counts can be a valuable indicator in screening hospital urinary tract infection.
ABSTRACT
BACKGROUND: Urine culture is still the standard laboratory procedure for definitive diagnosis of urinary tract infection. The author investigated the feasibility of eliminating the costs and time expended in examination of negative urine cultures by combining the Sysmex UF-100 (Toa Medical Electronics, Kobe, Japan) urine flow cytometer and urine strips to predict the outcome of urine cultures. METHODS: Seven hundred eighty one specimens were obtained from 661 males and 120 females (mean age, 66 years; range, 4~93 years). Urine cultures were performed with 10,000 colony forming units (CFU)/mL as the positive criterion. Each sample was analyzed by Clinitek Atlas (Bayer Co., Elkhart, IN, USA) using N-multistix SG urine strips, followed by identification and quantification of the formed elements on the Sysmex UF-100. RESULTS: Of the 781 urine specimens examined, 402 (51.5%) yielded positive cultures. The diagnostic performance of the UF-100 results for bacteria or WBC vs the urine strip results for leukocyte esterase or nitrite in comparison with the urine culture results were as follows: sensitivity 0.88 vs 0.80, specificity 0.77 vs 0.77, positive predictive value 0.80 vs 0.78, and negative predictive value 0.85 vs 0.79. The highest sensitivity (0.91) and the lowest false negative (0.05) were obtained when any one of the four tests was positive. CONCLUSION: The use of Sysmex UF-100 flow cytometer and urine strip results, seperately or in combination, does not accurately predict the outcome of urine cultures.