血清PCT对血流感染患者病原菌分布的鉴定作用研究

目的探讨血清降钙素原(PCT)在血流感染患者不同病原菌鉴别中的应用价值。方法采取回顾性分析的方法进行研究,选取2018年1月~2019年12月我院收治的血培养阳性血流感染患者512例,根据血培养结果分为革兰阴性菌感染组(G^-菌组)、革兰阳性菌感染组(G^+菌组)和真菌组。所有患者均于采取抗生素治疗前进行血培养和血清PCT水平检测,比较三组患者血清PCT水平的差异,并通过ROC曲线分析血清PCT水平在不同菌种感染鉴别中的检测效能。结果512例血培养阳性的血流感染患者中G^-菌占67.97%(348/512),G^+菌占25.98%(133/512),真菌占6.05%(31/512);G^-菌组患者血清PCT水平明显高于G^+菌组、真菌组患者,G^+菌组患者血清PCT水平明显高于真菌组患者(P<0.05);ROC曲线显示,当血清PCT Cut-off值分别为7.02 ng/mL、0.95 ng/mL、1.07 ng/mL时,血清PCT水平鉴别G-菌与G^+菌、G^-菌与真菌、G^+菌与真菌的检测效能最优,ROC AUC分别为0.68、0.73、0.64。结论血清PCT水平检测在不同菌种所致血流感染的鉴别诊断中有一定的应用价值,可作为该类患者病原菌种类评估的辅助手段。

Study on serum PCT for the identification of pathogenic bacteria in bloodstream infection

Objective To investigate the value of serum procalcitonin(PCT)for the identification of pathogenic bacteria in patients with bloodstream infection.Methods This retrospective analysis study was performed from January 2018 to December 2019.The participants were 512 patients with blood culture-positive bloodstream infection who were admitted to our hospital.According to the results of blood culture,all patients were divided into the Gram-negative bacteria infection group(the G^-bacteria Group),the Gram-positive bacteria infection group(G^+bacteria group)and the fungal group.The blood culture and serum PCT levels were detected before taking antibiotics.The serum PCT levels were compared among the three groups.ROC curve analysis was used to analyze the value of serum PCT for the identification of different pathogenic bacteria in bloodstream infection.Results Among the 512 patients with blood culture-positive bloodstream infection,G^-bacteria accounted for 67.97%(348/512),G^+bacteria accounted for 25.98%(133/512),and fungi accounted for 6.05%(31/512).The serum PCT levels of the G^-bacteria group was significantly higher than that of the G^+bacteria group and the fungal group,and the serum PCT levels of the G^+bacteria group was significantly higher than that of the fungal group(P<0.05).The ROC curve showed that when the cut-off values of serum PCT levels were 7.02 ng/mL,0.95 ng/mL and 1.07 ng/mL,respectively,the detection efficiency of serum PCT levels to identify G^-bacteria and G^+bacteria,G^-bacteria and fungi,G^+bacteria and fungi was the best,and the ROC AUC were 0.68,0.73 and 0.64,respectively.Conclusion The detection of serum PCT levels has certain application value for the differential diagnosis of bloodstream infections caused by different pathogenic bacteria,which can be used as an auxiliary method for the evaluation of pathogenic bacteria types in such patients.