Clinical application in the rapid diagnosis of urinary tract infection / 中华检验医学杂志

ABSTRACT

Objective To explore the value of UF-5000 urinary sediment analyzer in assistant examination of urinary tract infections by comparing the results of bacteria and white blood cells for UF-5000 with those of routine laboratory methods.Methods A total of 1 021 clean mid-stage urine samples suspected urinary tract infection were collected from the inpatients and outpatients of the Guangdong Provincial People's Hospital from October to December 2017.All specimens were detected by UF-5000 to evaluate the repeatability,linearity,carrying contamination rate,stability and efficiency of review flag by the instrument.Urine bacterial culture and clinical diagnosis were used as reference standards to calculate the coincidence rate of bacterial test results with purified bacteria,coincidence rate with bacterial culture,and agreement rate with cultured colonies.The urinary fungal culture and clinical diagnosis were used as reference standards to calculate the coincidence rate,sensitivity and specificity of the fungal test.Based on the results of bacterial culture and clinical diagnosis,UF-5000 was used to detect the efficacy of white blood cells and bacteria for the diagnosis of UTI.The results of UF-5000 detection,the results of urinary dry chemistry analyzer UC-3500,and the results of bacterial smear microscopy were compared with the results of urinary bacterial culture to determine the sensitivity,specificity and sensitivity of each method,and the coincidence rate of with the culture method.Statistical analysis was performed using variance analysis,Wilcoxon rank sum test,coincidence rate test (Kappa test),and receiver operating characteristic curve (ROC curve).Results UF-5000 was used to detect bacteria and white blood cells,UC-3500 was used to detect neutrophil esterase and nitrite with good repeatability,which met the EP5-A requirements;the linear relationship between bacteria was very good in the range of 0-10 000/ml,R=0.999;the contamination rate of UF-5000 was 0.00％ for bacteria,0.01％ for white blood cells.The rate of UC-3500 was qualified;the bacteria was stable for 2 hours at room temperature and 6 hours at 4 ℃,and the white blood cells were stable for 4 hours at room temperature and 4 hours at 4 ℃.Compared with UF-1000i,the review flag rate of UF-5000 reduced about 77.8％.The coincidence rate of detection and purification of UF-5000 bacteria was 100.0％(16/16),that of Gram-negative bacteria (G-) was 94.0％ (110/117),that of Gram-positive bacteria (G+) was 82.2％(37/45).The agreement rate of compared with bacterial colonies was 95.1％(216/227),and that of fungi culture was 77.1％ (749/972),that of sensitivity was 81.9％(118/144),and that of specificity was 76.2％(631/828).UF-5000,UC-3500,and bacterial smear microscopy showed that the ability of bacterial infection of urinary tract was compared with the results of traditional bacterial culture.The UF-5000 urinary tract infection flag (UTI) had the highest agreement rate,reaching 84.1％ (180/214).The sensitivity was 70.3％ (52/74),the specificity was 91.4％ (128/140);the coincidence rate of UC-3500 was 73.8％ (158/214),the sensitivity was 25.7％ (19/74),and the specificity was 99.3％ (139/140);the consistency of bacterial smear microscopy was 66.4％ (142/214),the sensitivity was 82.4％ (61/74),and the specificity was 57.9％ (81/140).Conclusion The total number of bacteria and white blood cell counted by UF-5000,the flag of bacterial and the UTI information,have partial clinical significance in the rapid detection of urinary tract infection.