Orrett F A
Department of Paraclinical Sciences, Faculty of Medical Sciences, Trinidad and Tobago, West Indies.
Cent Afr J Med. 1998 Nov;44(11):283-6.
To compare microbial prevalence (mixed versus pure), define microbial combination in mixed urine cultures among inpatients and outpatients and to identify factors that might allow a more objective interpretation of polymicrobic urine cultures.
Case series.
The study involved inpatients (hospitalized) and outpatients (those attending outpatient clinics and the accident and emergency department) of the San Fernando General Hospital in southern Trinidad.
Prevalence rates of bacterial isolates in mixed and pure cultures of urine specimens were determined using standard techniques and Kirby-Bauer disc diffusion methodology.
The results obtained showed that of 5,089 urine specimens, 1,491 (29.3%) yielded positive cultures. Of these positive cultures, 524 (35.1%) revealed significant polymicrobic bacteriuria. Eighty five percent yielded two organisms, 13.2% had three organisms and 1.8% had four organisms. Repeat cultures in 157 patients revealed the same organisms in only 57.3% of them. Almost all of the repeat cultures were from patients with in-dwelling Foley catheters. E. coli was the most common single isolate (42.8%), while Klebsiella, Enterobacter and Proteus organisms were most often encountered in mixed cultures. All isolates were relatively sensitive to routinely used antibiotics for urinary pathogens.
The prevalence rate of polymicrobic bacteriuria at our institution was 10.2%. More than 65% of positive cultures were from patients with Foley catheters on open drainage (inpatients) and closed drainage (outpatients). Most were men with out-flow obstruction who either refused surgery, were unfit for surgery, or had to wait long periods to be booked for surgery. No cases developed bacteremia secondary to bacteriuria. All urinary isolates were susceptible to routinely used antimicrobial agents.
比较微生物感染率（混合感染与单纯感染），确定住院患者和门诊患者混合尿培养中的微生物组合，并识别可能有助于更客观解读多微生物尿培养结果的因素。
病例系列研究。
该研究纳入了特立尼达岛南部圣费尔南多综合医院的住院患者（住院治疗）和门诊患者（就诊于门诊及急诊科的患者）。
采用标准技术和 Kirby-Bauer 纸片扩散法测定尿标本混合培养和纯培养中细菌分离株的感染率。
结果显示，在 5089 份尿标本中，1491 份（29.3%）培养结果为阳性。在这些阳性培养结果中，524 份（35.1%）显示存在显著的多微生物菌尿。85%的培养结果分离出两种微生物，13.2%分离出三种微生物，1.8%分离出四种微生物。157 例患者的重复培养结果显示，其中仅 57.3%的患者分离出相同的微生物。几乎所有重复培养均来自留置 Foley 导尿管的患者。大肠埃希菌是最常见的单一分离株（42.8%），而克雷伯菌属、肠杆菌属和变形杆菌属微生物最常出现在混合培养中。所有分离株对尿路病原体常用抗生素相对敏感。
我院多微生物菌尿的感染率为 10.2%。超过 65%的阳性培养结果来自采用开放引流（住院患者）和封闭引流（门诊患者）的 Foley 导尿管患者。大多数患者为男性，存在流出道梗阻，他们要么拒绝手术、不适合手术，要么需等待很长时间才能安排手术。未发生因菌尿继发的菌血症。所有尿分离株对常用抗菌药物敏感。
