Goswitz J J, Willard K E, Eastep S J, Shanholtzer C J, Olson M L, Pinnell M, Singleton T, Peterson L R
Department of Veterans Affairs Medical Center, Minneapolis, Minnesota.
Am J Clin Pathol. 1993 Feb;99(2):132-6. doi: 10.1093/ajcp/99.2.132.
The slide centrifuge (cytospin) Gram's-stain technique has been shown in previous studies to be a sensitive technique for detecting bacteriuria when compared to culture. The method concentrates urine sediment in a small defined area on a glass slide for Gram's staining. A positive test provides morphologic information about suspected pathogens. This study evaluated the cytospin technique using 788 urine specimens, on which routine culture was simultaneously performed, and compared both with clinical evidence for urinary tract infection. One hundred twelve of these specimens, which were cytospin positive and had a culture growing more than 100,000 CFU/mL, were assumed, by definition, to represent true urinary tract infection. Five hundred twenty-six specimens had negative cytospin and negative culture results (less than 1,000 CFU/mL) and were assumed, by definition, to rule out the diagnosis of urinary tract infection. Clinical data were evaluated for 56 cytospin-positive specimens in which culture results were less than 100,000 CFU/mL. Of these specimens, 37 were false positive (no clinical evidence of urinary tract infection), 9 had clinical evidence of urinary tract infection, and for the remaining 10, data regarding clinical status could not be interpreted. Seventy-one specimens were cytospin negative, with cultures growing more than 1,000 CFU/mL. Of these, only one patient had clinical evidence of a urinary tract infection, and his culture result was less than 10,000 CFU/mL. The predictive value of a negative cytospin test was 99.8% compared to clinical information, whereas the predictive value of a negative culture (less than 100,000 CFU/mL) was 98.4%.
与培养法相比，载玻片离心机（细胞离心涂片法）革兰氏染色技术在先前研究中已被证明是一种检测菌尿症的敏感技术。该方法将尿沉渣浓缩在载玻片上一个小的特定区域进行革兰氏染色。阳性检测可提供有关可疑病原体的形态学信息。本研究使用788份尿液标本评估了细胞离心涂片法，同时对这些标本进行了常规培养，并将两者与尿路感染的临床证据进行比较。根据定义，这些标本中有112份细胞离心涂片法呈阳性且培养出的菌落数超过100,000 CFU/mL，被认为代表真正的尿路感染。526份标本细胞离心涂片法和培养结果均为阴性（低于1,000 CFU/mL），根据定义，被认为可排除尿路感染的诊断。对56份细胞离心涂片法呈阳性但培养结果低于100,000 CFU/mL的标本的临床数据进行了评估。在这些标本中，37份为假阳性（无尿路感染的临床证据），9份有尿路感染的临床证据，其余10份的临床状态数据无法解读。71份标本细胞离心涂片法为阴性，但培养出的菌落数超过1,000 CFU/mL。其中，只有一名患者有尿路感染的临床证据，其培养结果低于10,000 CFU/mL。与临床信息相比，细胞离心涂片法阴性检测的预测值为99.8%，而培养结果阴性（低于100,000 CFU/mL）的预测值为98.4%。
