老年急性脑梗死患者肺部感染的病原学特征及与TLR4/NF-κB信号通路的相关性

Etiological characteristics of pulmonary infection in elderly patients with acute cerebral infarction and its correlation with TLR4/NF-κB signaling pathway

目的分析老年急性脑梗死患者肺部感染的病原学特征及与Toll样受体4(TLR4)/核转录因子κB(NF-κB)信号通路的相关性。方法抽取2020年7月至2022年7月南阳市中心医院收治的老年急性脑梗死肺部感染患者54例作为感染组,另抽取同期未合并肺部感染的84例患者作为未感染组。采集感染组患者鼻咽分泌物,采用全自动微生物计数检测仪检测患者的肺部感染情况,并参考美国临床和实验室标准协会抗菌药物敏感试验标准分析耐药性。采集两组患者肘静脉血,采用蛋白印迹技术检测TLR4和NF-κB,分析患者病原学与TLR4/NF-κB信号通路的相关性。结果54例老年急性脑梗死肺部感染患者中,共检出病原菌79株,其中革兰阴性菌57株(72.15%),以肺炎克雷伯菌、大肠埃希菌和铜绿假单胞菌为主;革兰阳性菌19株(24.05%),以肺炎链球菌和金黄色葡萄球菌为主;真菌3株(3.80%),以白假丝酵母为主。肺炎克雷伯菌、大肠埃希菌及铜绿假单胞菌对常规抗菌药物的耐药性均较高,对青霉素的耐药性最高,三种革兰阴性菌对头孢曲松和美罗培南的耐药性均较低;金黄色葡萄球菌和肺炎链球菌对常规抗菌药物耐药性均较高,其中对红霉素耐药性最高,对万古霉素和亚胺培南耐药性最低。感染组TLR4和NF-κB水平均低于未感染组(P<0.05)。结论老年急性脑梗死患者肺部感染病原菌以革兰阴性菌为主,且肺部感染患者TLR4/NF-κB信号通路出现明显的变化。

ObjectiveTo analyze the etiological characteristics of pulmonary infection in elderly patients with acute cerebral infarction and its correlation with toll like receptor 4(TLR4)/nuclear factor-κB(NF-κB)signaling pathway.MethodsFifty-four elderly patients with cerebral infraction complicated by pulmonary infection admitted to Nanyang Central Hospital from July 2020 to July 2022 were selected as the infection group,another 84 patients who did not have concurrent pulmonary infection during the same period were selected as the uninfected group.The nasopharyngeal secretions from patients in the infection group were collected,the pulmonary infection was detected using automatic microorganism quantitative analyzer.Drug resistance was analyzed according to the Clinical and Laboratory Standards Institute antimicrobial susceptibility testing guidelines.Elbow venous blood from two groups of patients were collected,and the levels of TLR4 and NF-κB were detected by Western blotting,and the correlation between etiological characteristics and TLR4/NF-κB signaling pathway was analyzed.ResultsA total of 79 strains of pathogenic bacteria were detected in the 54 elderly patients with acute cerebral infarction complicated by pulmonary infections.Among them,57 strains(72.15%)were Gram-negative bacteria,of which mainly were Klebsiella pneumoniae,Escherichiacoli coli and Pseudomonas aeruginosa;19 strains(24.05%)were Gram-positive bacteria,of which mainly were Streptococcus pneumoniae and Staphylococcus aureus;and 3 strains(3.80%)were fungi,of which mainly were Candida albicans.Drug resistance test showed that Klebsiella pneumoniae,Escherichia coli and Pseudomonas aeruginosa had high resistance to conventional antibiotics,while the resistance to penicillin was the highest,and the resistance to ceftriaxone and meropenem was relatively low.The Staphylococcus aureus and Streptococcus pneumoniae had high resistance to conventional antibiotics,while the resistance to erythromycin was the highest,and the resistance to vancomycin and imipenem was the lowest.The expression levels of TLR4 and NF-κB in the infection group were significantly lower than those in the non-infection group(P<0.05).ConclusionsGram-negative bacteria are the main pathogens of pulmonary infection in elderly patients with acute cerebral infarction,and pulmonary infection has close relation with the changes of TLR4/NF-κB signaling pathway.