Colodner R, Keness Y
Microbiology Laboratory, Central Emek Medical Center, Afula, Israel.
Isr Med Assoc J. 2000 Jul;2(7):563-5.
Many bedside urine culture devices have been developed with the aim of reliability, simplicity and use in both the physician's office and the clinical laboratory.
To compare a novel bedside urine culture device (DipStreak, Novamed Ltd., Israel) comprising a combination of MacConkey and Columbia CNA blood agar with conventional seeding on the same culture media.
A total of 1,000 urine specimens sent to our microbiology laboratory were simultaneously processed by both methods. Results were evaluated after 24 and 48 hours incubation at 37 degrees C.
Altogether, 171 (17.1%) and 124 (12.4%) specimens were defined as positive by the conventional method using cutoff values of 10(4) colony-forming units/ml and 10(5) CFU/ml respectively; 178 specimens (17.8%) were defined as contaminated. The sensitivity, specificity, positive and negative predictive values of DipStreak for urinary tract infection were 98.8%, 98.6%, 96% and 99.6% respectively, using a cutoff value of 10(4) CFU/ml, and 99.3%, 99.2%, 96% and 99.8% respectively, using cutoff value of 10(5) CFU/ml. Full agreement between both techniques was 95%.
The agreement rate between DipStreak and conventional seeding was remarkably high. These results suggest that DipStreak in the agar combination tested in this study is a useful and precise tool for diagnosing urinary tract infections.
为实现可靠性、简便性以及适用于医生办公室和临床实验室的目的,已研发出多种床边尿液培养装置。
比较一种新型床边尿液培养装置(DipStreak,以色列诺瓦梅德有限公司)与在相同培养基上进行的传统接种方法,该装置包含麦康凯琼脂和哥伦比亚CNA血琼脂的组合。
总共1000份送至我们微生物实验室的尿液标本同时采用这两种方法进行处理。在37摄氏度孵育24小时和48小时后评估结果。
总共,分别使用10⁴菌落形成单位/毫升和10⁵CFU/毫升的临界值,传统方法将171份(17.1%)和124份(12.4%)标本定义为阳性;178份标本(17.8%)被定义为污染。使用10⁴CFU/毫升的临界值时,DipStreak对尿路感染的敏感性、特异性、阳性预测值和阴性预测值分别为98.8%、98.6%、96%和99.6%,使用10⁵CFU/毫升的临界值时分别为99.3%、99.2%、96%和99.8%。两种技术之间的完全一致性为95%。
DipStreak与传统接种方法之间的一致率非常高。这些结果表明,本研究中测试的琼脂组合中的DipStreak是诊断尿路感染的一种有用且精确的工具。