Little P J, Peddie B A, Sincock A R
J Clin Pathol. 1980 Jan;33(1):58-60. doi: 10.1136/jcp.33.1.58.
The results of cultures carried out on urine collected by a midstream technique (MSU) have been compared with the results of cultures of urine collected by suprapubic bladder aspiration (SPA) in the same 903 patients. Comparisons indicate that when there are more than 100 x 10(6)/l (100 000/ml) Gram-negative bacteria in the midstream urine this finding is confirmed by suprapubic aspiration in 92% of patients, and in 70% when the urine contained this number of Gram-positive bacteria. When the culture contained more than one species (mixed organisms), the presence of infection was confirmed in only 11%. When there were 10-100 x 10(6)/l bacteria in the MSU the finding of Gram-negative bacilli still indicated urinary infection in 74% of patients, but the presence of Gram-positive organisms was confirmed in only 30% and mixed organisms in 2%. In asymptomatic patients, the presence of white cells in the urine was not helpful in confirming the diagnosis of infection. The nature of the organism found in the MSU is almost as important as the number of bacteria in assessing the validity of the result.
对903名患者采用中段尿技术（MSU）收集的尿液培养结果与耻骨上膀胱穿刺抽吸术（SPA）收集的尿液培养结果进行了比较。比较结果表明，当MSU尿液中革兰氏阴性菌数量超过100×10⁶/l（100 000/ml）时，耻骨上穿刺抽吸术在92%的患者中证实了这一结果；当尿液中含有此数量的革兰氏阳性菌时，这一比例为70%。当培养物包含不止一种菌种（混合菌）时，只有11%的患者被证实存在感染。当MSU中有10 - 100×10⁶/l细菌时，发现革兰氏阴性杆菌在74%的患者中仍提示存在泌尿系统感染，但革兰氏阳性菌的存在仅在30%的患者中得到证实，混合菌的存在仅在2%的患者中得到证实。在无症状患者中，尿液中白细胞的存在无助于确诊感染。在评估结果的有效性时，MSU中发现的菌种性质几乎与细菌数量同样重要。
