老年呼吸机相关性肺炎患者肠道菌群特征及其与疾病的相关性

探讨老年呼吸机相关性肺炎(VAP)患者肠道菌群特征及其与疾病的相关性, 为该类患者的治疗提供参考。

选择2018年1月至2020年1月在该院进行机械通气的患者141例, 根据是否发生VAP分为VAP组(n=67)和非VAP组(n=74), 同时选择同期在我院进行体检的健康者为对照组(n=50)。采用16S rRNA荧光定量PCR法检测3组研究对象肠道双歧杆菌和大肠埃希菌数量, 并计算B/E值。采用流式细胞仪检测T淋巴细胞亚群CD3⁺、CD3⁺CD4⁺、CD3⁺CD8⁺、CD4⁺/CD25⁺、CD8⁺/CD28^-以及CD8⁺/CD28⁺细胞水平。采用改良酶学分光光度法检测血浆D-乳酸水平。采用Pearson相关检验分析VAP组B/E值与免疫功能及血浆D-乳酸的相关性。

VAP组患者肠道双歧杆菌数量、B/E值显著低于非VAP组和对照组, 大肠埃希菌数量显著高于非VAP组和对照组(均P < 0.05);非VAP组和对照组比较差异亦均有统计学意义(均P < 0.05)。VAP组患者CD3⁺、CD3⁺CD4⁺、CD3⁺CD8⁺以及CD8⁺CD28⁺细胞水平显著高于非VAP组和对照组, CD8⁺CD28^-细胞水平显著低于非VAP组和对照组(均P < 0.05);非VAP组和对照组比较差异亦均有统计学意义(均P < 0.05)。VAP组患者血浆D-乳酸水平显著高于非VAP组和对照组, 非VAP组和对照组比较差异亦有统计学意义(均P < 0.05)。Pearson相关检验显示, VAP组患者B/E值与CD3⁺、CD3⁺CD4⁺、CD3⁺CD8⁺、CD8⁺/CD28⁺细胞以及血浆D-乳酸水平呈显著负相关, 与CD8⁺/CD28^-细胞呈显著正相关(均P < 0.05)。

VAP患者存在肠道菌群失衡, 且VAP与肠道菌群失衡存在相关性, 促进肠道菌群平衡有助于VAP的防治。

Intestinal flora characteristics in elderly patients with ventilator-associated pneumonia and their correlation with disease

ObjectiveTo explore the intestinal flora characteristics and their correlation with disease in elderly patients with ventilator-associated pneumonia(VAP) and their correlation, and to provide reference for the treatment of these patients.MethodsA total of 141 patients who underwent mechanical ventilation in the hospital were selected between January 2018 and January 2020. According to whether VAP occurred or not, the patients were divided into VAP group(n=67) or non-VAP group(n=74). Healthy individuals undergoing physical examination in the hospital during the same period were enrolled as control group(n=50). 16 S rRNA fluorescent quantitative PCR was used to detect the counts of intestinal Bifidobacteria and Escherichia coli in the three groups, and the B/E value was calculated. Flow cytometry was applied to detect the levels of T lymphocyte subsets CD3+, CD3+CD4+, CD3+CD8+, CD4+/CD25+, CD8+/CD28- and CD8+/CD28+ cells. Plasma D-lactic acid level was detected using modified enzymatic spectrophotometry, and Pearson correlation test was used to analyze the correlation between B/E value in VAP group and immune function and plasma D-lactic acid.ResultsThe count of Bifidobacteria and B/E value in VAP group were significantly lower, while the count of Escherichia coli was significantly higher compared to non-VAP group and control group respectively(all P < 0.05), and there were statistically significant differences between non-VAP group and control group(all P < 0.05). The levels of CD3+, CD3+CD4+, CD3+CD8+ and CD8+/CD28+ cells in VAP group were significantly higher, while the level of CD8+/CD28-was significantly lower than non-VAP group and control group respectively(all P < 0.05), and the differences between non-VAP group and control group were also statistically significant(all P < 0.05). The level of plasma D-lactic acid in VAP group was significantly higher than that in non-VAP group and control group, and there was a statistical difference between non-VAP group and control group(all P < 0.05). Pearson correlation test showed that the B/E value in VAP group was significantly negatively correlated with CD3+, CD3+CD4+, CD3+CD8+ and CD8+/CD28+ cells and plasma D-lactic acid level, and was significantly positively correlated with CD8+/CD28-(all P < 0.05).ConclusionThere is intestinal flora imbalance among patients with VAP, and VAP is related to intestinal microecological imbalance. Promoting intestinal microecological balance is helpful for the prevention and treatment of VAP.