呼吸机相关性肺炎患者病原菌分布及血清HMGB1、PCT、CGRP水平变化的临床评价

探讨呼吸机相关性肺炎(VAP)患者感染病原菌分布情况以及血清高迁移率族蛋白B1(HMGB1)、降钙素原(PCT)、降钙素原基因相关肽(CGRP)水平的变化, 为该类患者的治疗提供参考。

选择2018年1月至2019年9月在我院接受治疗的机械通气患者137例, 其中符合VAP诊断标准的86例患者作为感染组, 其余51例作为未感染组; 选择同期在我院进行体检的60例健康者作为对照组。采用酶联免疫吸附法(ELISA)检测血清HMGB1、PCT、CGRP水平, 利用受试者工作曲线(ROC)预测血清HMGB1、PCT、CGRP对VAP的诊断价值。

137例机械通气治疗患者中有86例患者发生感染, 感染率为62.77%。86例感染患者样本共培养出95株致病菌, 其中革兰阴性菌(G^-)56株, 占58.95%;革兰阳性菌(G⁺)36株, 占37.89%;真菌3株, 占3.16%。感染组和未感染组患者血清HMGB1、PCT水平均高于对照组, CGRP水平低于对照组(均P < 0.05);感染组患者血清HMGB1、PCT水平均高于未感染组, CGRP水平低于未感染组(均P < 0.05)。ROC结果显示, 血清HMGB1、PCT、CGRP对VAP诊断的曲线下面积(AUC)分别为0.846、0.845、0.769, 最佳截断值分别为43.473μg/L、1.966μg/L、112.778 ng/L, 灵敏性分别为73.26%、65.12%、82.65%, 特异性分别为88.24%、94.12%、68.63%;三者联合诊断的AUC为0.932, 灵敏性和特异性分别为83.72%、94.12%。

VAP患者感染病原菌主要为革兰阴性菌。VAP患者血清HMGB1、PCT呈高表达, CGRP呈低表达, 三者对预测VAP均有一定效果, 其中三者联合诊断的效果最好, 具有一定的临床应用价值。

Pathogen distribution and clinical evaluation of serum HMGB1, PCT and CGRP changes in patients with ventilator-associated pneumonia

ObjectiveTo observe the distribution of pathogenic bacteria in patients with ventilator-associated pneumonia(VAP) and the levels of serum high mobility group protein B1(HMGB1), procalcitonin(PCT), calcitonin gene-related peptide(CGRP) and their clinical significance, providing a reference for the treatment.MethodsA total of 137 patients with mechanical ventilation who were treated in our hospital from January 2018 to September 2019 were enrolled, among whom 86 patients who met the VAP diagnostic criteria were selected as the infection group, and the remaining 51 patients as the noninfection group, with another 60 healthy individuals who received examination at the same time in our hospital as the control group. There were no significant differences in gender and age between the groups. Enzyme linked immunosorbent assay(ELISA) was used to detect the levels of serum HMGB1, PCT and CGRP, and the receiver operating characteristic curve(ROC) was used to predict the diagnostic values of the indexes.ResultsEighty-six of the 137 patients treated with mechanical ventilation were infected, the infection rate was 62.77%, from whom 95 strains of pathogenic bacteria were isolated, of which 56 strains(58.95%) were Gram-negative(G-), 36 strains(37.89%) were Gram-positive bacteria(G+), and 3 strains(3.16%) were fungi. The levels of serum HMGB1 and PCT in the infection group and noninfection group were higher, while that of CGRP was lower than in the control group, respectively(all P < 0.05); the levels of HMGB1 and PCT in the infection group were higher, while that of CGRP was lower than in the noninfection group, respectively(all P < 0.05). ROC showed that the areas under curve(AUCs) of serum HMGB1, PCT and CGRP in the diagnosis of VAP were 0.846, 0.845 and 0.769 respectively, the best cutoff values were 43.473 μg/L, 1.966 μg/L and 112.778 ng/L respectively, the sensitivities were 73.26%, 65.12% and 82.65%, and the specificities were 88.24%, 94.12% and 68.63%, respectively. The AUC of combined diagnosis was 0.932, and sensitivity and specificity were 83.72% and 94.12%, respectively.ConclusionThe main pathogen of VAP is Gram negative bacteria(G-). The serum HMGB1 and PCT are highly expressed in VAP patients, and CGRP is lowly expressed, which have a certain diagnostic value for the prediction of VAP, and combination of the three was more effective for the diagnosis, with a certain clinical significance.