降钙素原C反应蛋白及血小板计数在鉴别早产儿晚发型败血症病原菌中的参考意义

The role of procalcitonin,C-reactive protein and platelet count in identifying pathogens of late-onset sepsis in premature infants

目的探讨降钙素原(PCT)、C反应蛋白(CRP)及血小板计数(PLT)在早期鉴别早产儿晚发型败血症病原菌种类中的意义。方法通过回顾性分析,比较45例确诊晚发型败血症早产儿在发病早期检测的PCT、CRP、PLT水平在不同病原菌感染组中的差异,其中革兰阴性菌组26例,革兰阳性菌组7例,真菌组12例,以同期住院的20例非感染早产儿作为对照组,并了解病原菌的分布特点。结果革兰阴性菌组PCT水平高于其余三组,差异有统计学意义(P<0.05);真菌组CRP水平在四组中最高,PLT水平在四组中最低,差异均有统计学意义(P<0.05)。PCT水平高于9.7ng/ml时,提示革兰阴性菌感染可能性大,灵敏度为100.0%,特异度为92.3%。CRP水平高于20.8mg/dL时,提示真菌感染可能性大,灵敏度为91.7%,特异度为79.2%。PLT水平低于82×10^9/L时,提示真菌感染可能性大,灵敏度为94.3%,特异度为66.6%(P=0.000)。病原菌中革兰阴性菌占57.8%(以肺炎克雷伯菌为主),革兰阳性菌占15.6%,真菌占26.7%。结论PCT、CRP、PLT水平对于早期鉴别早产儿晚发型败血症病原菌种类有重要参考意义,早产儿晚发型败血症病原菌以肺炎克雷伯菌及念珠菌属为主,为临床早期合理选择抗菌药物提供依据。

Objective To explore the significance of procalcitonin(PCT), C-reactive protein(CRP) and platelet count(PLT) in early identification of pathogenic bacteria of late-onset sepsis in premature infants. Methods Through retrospective analysis, the differences of PCT, CRP and PLT levels of 45 premature infants with late-onset sepsis in our department were compared among different pathogenic bacteria infection groups which were divided into Gram-negative bacteria group( n =26), Gram-positive bacteria group( n =7), and fungi group( n =12). Twenty non-infectious premature infants hospitalized in the same period were taken as the control group, and the distribution characteristics of pathogenic bacteria were studied. Results The level of PCT in the Gram-negative bacteria group was significantly higher than that in the other three groups( P <0.05);the level of CRP was the highest, and the level of PLT was the lowest in the fungi group among the four groups, with statistically significant differences( P <0.05). When the level of PCT was higher than 9.7 ng/ml, it was more likely to be infected by Gram-negative bacteria, and the sensitivity and specificity were 100.0% and 92.3% respectively. When the level of CRP was higher than 20.8 mg/dL, it was more likely to be infected by fungi, and the sensitivity and specificity were 91.7% and 79.2% respectively. When the level of PLT was lower than 82×10^9/L, it was more likely to be infected by fungi, and the sensitivity and specificity were 94.3% and 66.6% respectively( P =0.000). Gram-negative bacteria accounted for 57.8% of the pathogenic bacteria which was mainly Klebsiella pneumoniae;Gram-positive bacteria accounted for 15.6% and fungi accounted for 26.7%. Conclusion The levels of PCT, CRP and PLT have important reference significance for early identification of pathogenic bacteria of late-onset sepsis in premature infants. Klebsiella pneumoniae and Candida are the main pathogens of late-onset sepsis in premature infants, which provides a basis for early and rational selection of antibiotics in clinics.