Cheung Felix, Loeb Charles A, Croglio Michael P, Waltzer Wayne C, Weissbart Steven J
1 Department of Urology, Stony Brook University Hospital, Stony Brook University Medical Center , Stony Brook, New York.
2 Stony Brook University School of Medicine , Stony Brook, New York.
J Endourol. 2017 Sep;31(9):942-945. doi: 10.1089/end.2017.0157. Epub 2017 Jun 27.
Determining whether bacterial presence in urine microscopy represents infection is important as ureteral stent placement is indicated in patients with obstructing urolithiasis and infection. We aim to investigate whether the presence of bacteria on urine microscopy is associated with other markers of infection in patients with obstructing urolithiasis presenting to the emergency room.
We performed a cross-sectional study of 199 patients with obstructing urolithiasis and divided patients into two groups according to the presence of bacteria on urine microscopy. The primary outcome was serum white blood cell count and secondary outcomes were objective fever, subjective fever, tachycardia, pyuria, and final urine culture. Univariate and multivariate analysis were used to assess whether the presence of bacteria on microscopy was associated with other markers of infection.
The study included 72 patients in the bacteriuria group and 127 without bacteriuria. On univariate analysis, the presence of bacteria was not associated with leukocytosis, objective fever, or subjective fever, but it was associated with gender (p < 0.001), pyuria (p < 0.001), positive nitrites (p = 0.001), positive leukocyte esterase (p < 0.001), and squamous epithelial cells (p = 0.002). In a multilinear regression model including the presence of squamous cells, age, and sex, the presence of bacteriuria was not related to serum white blood cell count (coefficient -0.47; 95% confidence interval [CI] -1.1, 0.2; p = 0.17), heart rate (coefficient 0.85; 95% CI -2.5, 4.2; p = 0.62), presence of subjective or objective fever (odds ratio [OR] 1.5; 95% CI 0.8, 3.1; p = 0.18), or the presence of squamous epithelial cells (coefficient -4.4; 95% CI -10, 1.2; p = 0.12). However, the presence of bacteriuria was related to only the degree of pyuria (coefficient 16.4; 95% CI 9.6, 23.3; p < 0.001).
Bacteria on urine microscopy is not associated with other markers of systemic infection and may largely represent a contaminant. Renal colic may be a risk factor for providing a contaminated urine specimen.
确定尿镜检中细菌的存在是否代表感染很重要，因为对于患有梗阻性尿路结石并伴有感染的患者需要放置输尿管支架。我们旨在研究在急诊室就诊的梗阻性尿路结石患者中，尿镜检发现细菌与其他感染标志物之间是否存在关联。
我们对199例梗阻性尿路结石患者进行了一项横断面研究，并根据尿镜检中细菌的存在情况将患者分为两组。主要结局指标是血清白细胞计数，次要结局指标是客观发热、主观发热、心动过速、脓尿和最终的尿培养结果。采用单因素和多因素分析来评估镜检中细菌的存在与其他感染标志物是否相关。
该研究包括72例菌尿组患者和127例无菌尿组患者。单因素分析显示，细菌的存在与白细胞增多、客观发热或主观发热无关，但与性别（p < 0.001）、脓尿（p < 0.001）、亚硝酸盐阳性（p = 0.001）、白细胞酯酶阳性（p < 0.001）和鳞状上皮细胞（p = 0.002）有关。在一个包含鳞状细胞、年龄和性别的多线性回归模型中，菌尿的存在与血清白细胞计数（系数 -0.47；95%置信区间[CI] -1.1，0.2；p = 0.17）、心率（系数0.85；95% CI -2.5，4.2；p = 0.62）、主观或客观发热的存在（比值比[OR] 1.5；95% CI 0.8，3.1；p = 0.18）或鳞状上皮细胞的存在（系数 -4.4；95% CI -10，1.2；p = 0.12）均无关联。然而，菌尿的存在仅与脓尿程度有关（系数16.4；95% CI 9.6，23.3；p < 0.001）。
尿镜检中的细菌与全身感染的其他标志物无关，可能主要代表污染物。肾绞痛可能是导致尿标本受污染的一个危险因素。
