血培养阳性报警时间对新生儿凝固酶阴性葡萄球菌血流感染的诊断研究

The alarm time of positive blood culture in diagnosing the neonatal bloodstream infection of coagulase negative Staphylococcus

目的评价血培养阳性报警时间(TTP)对新生儿凝固酶阴性葡萄球菌血流感染的诊断价值,为临床治疗提供参考依据。方法回顾性分析2007年1月-2012年12月血培养凝固酶阴性葡萄球菌阳性的346例新生儿,分为血流感染组145例和血培养污染组201例;对所有新生儿进行血培养分析,比较血流感染患者与血培养污染患者TTP的差异,计算TTP对血流感染组与血培养污染组鉴别诊断的灵敏度、特异度、阳性预测值及阴性预测值。结果共调查1 345例新生儿,其中346例新生儿血培养凝固酶阴性葡萄球菌阳性,阳性率为25.72%;血流感染组新生儿的TTP为(9.35±4.53)h,血培养污染组新生儿的TTP为(17.45±7.69)h,两组差异有统计学意义(P<0.01)。结论血培养阳性报警时间是很好的辅助诊断新生儿凝固酶阴性葡萄球菌血流感染的方法,以TTP≤12h为折点,可有效的鉴别诊断新生儿凝固酶阴性葡萄球菌血流感染和血培养污染。

OBJECTIVE To evaluate the diagnose value of positive blood culture （Time to positive ,TTP） to the neonatal bloodstream infection of coagulase negative Staphylococcus so as to provide clinical references . METHODS A retrospective analysis was conducted from 346 neonatal with positive coagulase negative staphylococ‐cus in blood culture from Jan .2007 to Dec .2012 .They were divided into bloodstream infection group （n=145） and blood culture contamination group （n=201） .All the neonatal were conducting blood culture analysis .Then the TTP of bloodstream infection group was compared with blood culture contamination group and the influence of TTP was calcu leted to the sensitivity ,specificity ,positive predictive value and negative predictive value of the dif‐ferential diagnosis of the two groups .RESULTS Among the 1345 neonatal patients ,346 were found positive in co‐agulase negative Staphylococcus ,the positive rate was 25 .72% .The TTP in the bloodstream infection group was （9 .35 ＆#177; 4 .53）h ,and it was （17 .45 ＆#177; 7 .69）h in the blood culture contamination group .The difference is signifi‐cant .（P＆lt; 0 .01） .CONCLUSION The TTP is a good diagnosis method for clinical diagnosis of neonatal blood‐stream infection of coagulase negative Staphylococcus .Setting TTP ≤ 12 h as the cut‐off value ,it can be effective in discriminating the bloodstream infection and blood culture contamination .