Differences in the gut and pharyngeal microbiomes before and after treatment of an acute exacerbation of chronic obstructive pulmonary disease.

This study investigated the gut microbiota and pharyngeal microbiome before and after treatment of an acute exacerbation of chronic obstructive pulmonary disease (AECOPD). The abundance and diversity of microorganisms in the gut and pharynx were examined in 24 patients before and after treatment of AECOPD. Enzyme-linked immunosorbent assay was used to detect inflammatory factors in venous blood and 16S rDNA sequencing was performed. The concentration of short-chain fatty acids (SCFAs) in fecal samples was measured by chromatography-mass spectrometry. The results indicated that the diversity and richness of the gut microbiota decreased post-treatment. The linear discriminant analysis effect size (LEfSe) algorithm revealed an increase in the abundance of f_Dietziaceae, g_Dietzia, g_Megasphaera, g_Robinsoniella, s_Salivarius, and s_Peoriensis in the gut after treatment. There was also a post-treatment decrease in the richness of the pharyngeal microbiome. LEfSe revealed a high abundance of p_Actinobacteria, f_Bacteriodaceae, o_Thermales, g_Bacteroides, and g_Thermus in the pharynx before treatment, and an increased abundance of o_Enterobacterales, f_Enterobacteriaceae, f_Ruminococcaceae, and g_Faecalibacterium after treatment. There were no post-treatment changes in SCFA levels. However, the serum C-reactive protein level decreased after treatment. Levels of other inflammatory factors, including tumor necrosis factor-alpha, interleukin (IL)-1β, IL-6, IL-10, transforming growth factor-beta, IL-23, IL-17, and interferon-gamma, were consistent before and after treatment. In this study, changes in the gut microbiota and pharyngeal microbiome occurred after treatment for AECOPD, with no changes in levels of SCFAs or inflammatory factors, except for a decrease in the C-reactive protein level.