Brodersen Hans-Peter, Beckers Benno, Clauss Matthias, vom Dahl Jürgen, Floege Jürgen, Janssen Ulf
Department of Cardiology, Nephrology and Intensive Care Medicine, Krankenhaus St Franziskus, Kliniken Maria Hilf, Mönchengladbach, Germany.
J Nephrol. 2007 Jul-Aug;20(4):462-7.
Central venous hemodialysis catheter-related infection is a major cause of morbidity and mortality in the hemodialysis (HD) population. Due to an impaired immune response, symptoms and signs of infection may not be obvious, and thus bacteremia is often diagnosed and treated protractedly. In contrast, induction of the acute phase response is frequently observed in HD patients even without infection. Moreover, positive catheter cultures may result from contamination, asymptomatic colonization or infection. The aim of the present study was to compare the number of colonies from HD catheter tips, with symptoms and signs of infection in HD patients.
In a 10-year, single-center study, 53 HD patients (29 men, 24 women; mean age 66 +/- 10 years) who had their dialysis catheters removed were divided into 3 groups according to the number of colonies growing after rolling the catheter tip across blood agar (group I: <15 colonies [n=22], II: 15-50 colonies [n=15], III: >50 colonies [n=16]).
The maximum white blood cell (WBC) count did not differ significantly between patients with low- and high-density colonization (group I: 11.746 +/- 9.680 WBC/microL vs. group III: 13.479 +/- 6.252 WBC/microL, p=NS) while maximum C-reactive protein (CRP) levels were higher in patients with high-density colonization (group I: 8.6 +/- 6.8 vs. group III: 19.2 +/- 12.2 mg/dL, p<0.05). Density of bacterial colonization was associated with the maximum body temperature (group I: 37.6 degrees C +/- 1.1 degrees C vs. 38.7 degrees C +/- 0.9 degrees C, p<0.05). Moreover patients with high-density colonization showed increased bacteremia (group I: 33% vs. group III: 93%, p<0.01) as well as an increased mortality due to septicemia (group I: 9% vs. group III: 50%, p<0.01). Patients of group II exhibited intermediate values in all analyses.
The semiquantitative culture technique can help to differentiate between contamination and infection of central venous HD catheters and provides important prognostic information in dialysis patients.
中心静脉血液透析导管相关感染是血液透析（HD）人群发病和死亡的主要原因。由于免疫反应受损，感染的症状和体征可能不明显，因此菌血症常常被延迟诊断和治疗。相比之下，即使在没有感染的HD患者中也经常观察到急性期反应的诱导。此外，导管培养阳性可能是由于污染、无症状定植或感染所致。本研究的目的是比较HD患者导管尖端菌落数量与感染症状和体征之间的关系。
在一项为期10年的单中心研究中，53例接受透析导管拔除的HD患者（29例男性，24例女性；平均年龄66±10岁）根据导管尖端在血琼脂上滚动后生长的菌落数量分为3组（I组：<15个菌落[n=22]，II组：15 - 50个菌落[n=15]，III组：>50个菌落[n=16]）。
低密度定植和高密度定植患者的最高白细胞（WBC）计数无显著差异（I组：11.746±9.680个WBC/μL vs. III组：13.479±6.252个WBC/μL，p=无统计学意义），而高密度定植患者的最高C反应蛋白（CRP）水平更高（I组：8.6±6.8 vs. III组：19.2±12.2mg/dL，p<0.05）。细菌定植密度与最高体温相关（I组：37.6℃±1.1℃ vs. 38.7℃±0.9℃，p<0.05）。此外，高密度定植患者的菌血症增加（I组：33% vs. III组：93%，p<0.01），败血症导致的死亡率也增加（I组：9% vs. III组：50%，p<0.01）。II组患者在所有分析中表现出中间值。
半定量培养技术有助于区分中心静脉HD导管的污染和感染，并为透析患者提供重要预后信息。
