血培养实验室污染菌群分布与阳性报警时间的判断

Laboratory contamination bacterial distribution of blood culture and judgment of positive alarm time

目的通过回顾西安交通大学第一附属医院血培养病原菌的检出情况并进行污染菌判定的实验室检查,了解血培养污染情况,为临床判断血培养污染提供实验室证据与经验。方法对西安交通大学第一附属医院2014年1-12月的血培养标本进行回顾性分析,根据实验室对血培养污染的评估方案,结合细菌种类、阳性报告时间进行综合分析,判断血培养污染并分析其细菌种类与构成。结果该研究共包含血培养17 941瓶,其中阴性7 193套,阳性837套,成套率为89.5%。血培养阳性率为10.4%,其中污染率为1.6%,主要污染菌为凝固酶阴性葡萄球菌,污染菌阳性报警时间平均值在需氧瓶与厌氧瓶分别为1.34与1.29d。双瓶结果不一致的培养结果中多见致病菌与条件致病菌。结论血培养污染菌主要为皮肤常驻菌,为降低血培养污染率,严格执行血培养采血规范具有重要意义,同时需重视住院患者采血环境的消毒。

Objective To understand the bacterial contamination situation of blood culture to provide the laboatory evidence and experience for the clinical judgment of blood culture contamination by retrospectively analyzing the pathogenic bacterial detection situation of blood culture and laboratory judgment detection of contamination bacteia in the First Affiliated Hospital of Xi′an First Affiliated Hospital of Xi′an Jiaotong University Jiaotong University . Methods The blood culture samples collected in the First Affiliated Hospital of Xi′an Jiaotong University from Janary 2014 to December 2014 were retrospectively analyzed .The comprehensive analysis was performed according to the laboratory assessment scheme on blood culture contamination and combining with the bacterial species and positive report time for judging the blood culture contamination and analyzing the bacterial species and their composition . Results This research contained 17 941 bottles of blood culture ,including 7 193 sets of negative and 837 sets of positive ,the complete set rate was 89 .5% .The positive rate of blood culture was 10 .4% ,of which the contamination rate was 1 .6% .The main contaminated bacteria were coagulase negative staphylococcus ,and average alarm time of contaminated bacteria in aerobic and anaerobic bottles was 1 .34 ,1 .29 d ,respectively .The pathogenic bacteria and opportunistic pathogenic bacteria were common in the culture results of two bottles with the inconsistent culture results . Conclusion Blood culture contaminating bacteria are mainly skin resident bacteria .To reduce the contamination rate of blood culture ,it is vital to strictly execute the standard blood sampling procedure ,and emphasize the sterilization of blood‐collecting environment in hospitalized patients .