肝移植术后细菌感染的非培养快速诊断方法

目的 通过对拟诊感染的患者外周血标本行细菌PCR检测和内毒素鲎试验,确立细菌感染的诊断,并分类检出革兰阴、阳性菌,从而指导临床用药.方法 以2005年10月至2007年10月在我院移植中心接受肝脏移植的50例患者为研究对象,分别抽取术前或手术当日(D0)、术后第1天(D1)、D7、D14 4个时段的外周血标本.样本处理后,行细菌PCR检测、细菌内毒素鲎试验.结果 细菌PCR检测的敏感度为66.7%,特异度为95.0%,诊断符合度为78.0%;内毒素鲎试验敏感度为84.2%,特异度为83.9%,诊断符合度为84.0%.两试验平均总耗时为3 h.结论 PCR试验阳性,内毒素鲎试验阴性,提示阳性菌感染;PCR试验阳性,内毒素鲎试验阳性,提示阴性菌感染或混和感染;PCR试验阴性,提示无严重感染.两试验诊断速度明显快于传统的培养方法,可以作为早期诊断的指标.

The Non-cultrural methods for rapid diagnosis of infection after liver transplanation

Objective To verify the diagnosis of the bacterial infections and to identify the pathogens, by PCR detection and bacterial endotoxin limulus test. Methods This study enrolled 50 patients receiving liver al-lografts from October 2005 to October 2007 in Ruijin Hospital. Peripheral blood samples were taken on DO, D1, D7 and D14. After preparation of the samples, PCR detection, bacterial endotoxin limulus test were performed. Results The sensitivity, specificity, and accuracy in the diagnosis was 66.7% ,95.0%, and 78.0% for the PCR, and 84.2%,83.9%,and 84.0% for limulus test respectively. It took 3 hours on average for the accomplishment of all these tests. Conclusions Positive PCR test plus negative limulus test suggest G+ infection, which may need the drugs targeting on G+ bacteria;positive PCR test plus positive limulus test, suggest G-infection or mixed infection, which may need drugs against the G-bacteria;negative PCR test, suggests the lack of severe infection. PCR test and limulus test were both remarkably faster than traditional cultural methods in diagnosis.