Pezzlo M T, Tan G L, Peterson E M, de la Maza L M
J Clin Microbiol. 1982 Mar;15(3):468-74. doi: 10.1128/jcm.15.3.468-474.1982.
A study was conducted to compare three automated systems and the Gram stain for their ability to detect significant bacteriuria. A total of 1,000 urine specimens were evaluated by Autobac MTS (General Diagnostics), Auto Microbic system (AMS; Vitek Systems, Inc.), and MS-2 (Abbott Laboratories) and compared with a semiquantitative culture plate method. Two hundred thirty-nine (23.9%) specimens had colony counts of >10(5) colony-forming units (CFU)/ml by the culture plate method (group I). Of these, 204 (85.3%) were positive by Autobac, 198 (82.8%) were positive by AMS, and 179 (74.9%) were positive by MS-2. When pure cultures of diphtheroids, lactobacilli, and viridans streptococci not group D were considered contaminants and therefore excluded, there were 118 specimens containing pure cultures of probable pathogens. The percentage of significant isolates detected was 97.4% (115 of 118) by the Gram stain, 96.6% (114 of 118) by Autobac, and 95.8% (113 of 118) by AMS and MS-2. The average detection time for all organisms was 2.2 h by Autobac, 6.1 h by AMS, and 1.8 h by MS-2; therefore, all three methods were more rapid than the 18- to 24-h standard plate culture method. One hundred sixty-one (16.1%) specimens had colony counts of 10(4) to 10(5) CFU/ml (group II). The probable pathogens not detected in this group were two (1.2%) by Autobac and MS-2 and three by AMS (1.9%). The average detection time for group II was 4.2 h by Autobac, 8.9 h by AMS, and 3.8 h by MS-2. Six hundred specimens had colony counts of <10(4) CFU/ml. Of these, 188 had colony counts equal to 10(3) and <10(4) CFU/ml (group III), and 412 cultures were below detectable limits by the standard plate method (group IV). Less than 37 and 15% of groups III and IV, respectively, were detected by instrumentation. Average detection times for groups III and IV were 4.6 and 4.8 h by Autobac, 10 and 11 h by AMS, and 4.2 and 4.4 h by MS-2. The cost of supplies and technical time with Gram stain, Autobac, and MS-2, when used as screening methods, were comparable and considerably less expensive than for the reference method. The AMS was the least expensive system when the cost for identifying probable pathogens was included.
开展了一项研究，比较三种自动化系统及革兰氏染色检测显著菌尿的能力。采用自动细菌检测仪MTS（通用诊断公司）、自动微生物系统（AMS；维泰克系统公司）和MS-2（雅培实验室）对总共1000份尿液标本进行评估，并与半定量培养平板法进行比较。通过培养平板法，239份（23.9%）标本的菌落计数>10⁵ 菌落形成单位（CFU）/毫升（第一组）。其中，自动细菌检测仪检测出204份（85.3%）呈阳性，AMS检测出198份（82.8%）呈阳性，MS-2检测出179份（74.9%）呈阳性。当将类白喉杆菌、乳酸杆菌和非D组草绿色链球菌的纯培养物视为污染物并予以排除时，有118份标本含有可能病原菌的纯培养物。革兰氏染色检测出显著分离株的比例为97.4%（118份中的115份），自动细菌检测仪为96.6%（118份中的114份），AMS和MS-2为95.8%（118份中的113份）。自动细菌检测仪检测所有微生物的平均时间为2.2小时，AMS为6.1小时，MS-2为1.8小时；因此，这三种方法均比18至24小时的标准平板培养法更快。161份（16.1%）标本的菌落计数为10⁴至10⁵ CFU/毫升（第二组）。该组中自动细菌检测仪和MS-2未检测出的可能病原菌有2份（1.2%），AMS未检测出的有3份（1.9%）。第二组的平均检测时间自动细菌检测仪为4.2小时，AMS为8.9小时，MS-2为3.8小时。600份标本的菌落计数<10⁴ CFU/毫升。其中，188份的菌落计数等于10³且<10⁴ CFU/毫升（第三组），412份培养物通过标准平板法低于可检测限（第四组）。仪器检测出第三组和第四组的比例分别低于37%和15%。自动细菌检测仪检测第三组和第四组的平均时间分别为4.6小时和4.8小时，AMS为10小时和11小时，MS-2为4.2小时和4.4小时。革兰氏染色、自动细菌检测仪和MS-2用作筛查方法时，耗材成本和技术时间相当，且比参考方法便宜得多。若将鉴定可能病原菌的成本计算在内，AMS是最便宜的系统。
