Analysis of sputum microbial flora in chronic obstructive pulmonary disease patients with different phenotypes during acute exacerbations.

BACKGROUND: Increasing studies have shown that the imbalance of the respiratory microbial flora is related to the occurrence of COPD, the severity and frequency of exacerbations and mortality.However, it remains unclear how the sputum microbial flora differs during exacerbations in COPD patients manifesting emphysema phenotype, chronic bronchitis with emphysema phenotype and asthma-COPD overlap phenotype. METHODS: Sputum samples were obtained from 29 COPD patients experiencing acute exacerbations who had not received antibiotics or systemic corticosteroids within the past four weeks.Patients were divided into three groups;emphysema phenotype(E);chronic bronchitis with emphysema phenotype(B+E) and asthma-COPD overlap phenotype(ACO).We utilized metagenomic Next Generation Sequencing (mNGS) technology to analyze the sputum microbial flora in COPD patients with different phenotypes during exacerbations. RESULTS: There was no significant difference in alpha diversity and beta diversity among three groups.The microbial flora composition was similar in all three groups during exacerbations except for a significant increase in Streptococcus mitis in ACO.Through network analysis,we found Candidatus Saccharibacteria oral taxon TM7x and Fusobacterium necrophorum were the core nodes of the co-occurrence network in ACO and E respectively.They were positively correlated with some species and play a synergistic role.In B+E,Haemophilus pittmaniae and Klebsiella pneumoniae had a synergistic effect.Besides,some species among the three groups play a synergistic or antagonistic role.Through Spearman analysis,we found the relative abundance of Streptococcus mitis was negatively correlated with the number of hospitalizations in the past year(r = -0.410,P = 0.027).We also observed that the relative abundance of Prevotella and Prevotella melaninogenica was negatively correlated with age(r = -0.534,P = 0.003;r = -0.567,P = 0.001),while the relative abundance of Streptococcus oralis and Actinomyces odontolyticus was positively correlated with age(r = 0.570,P = 0.001;r = 0.480,P = 0.008).In addition,the relative abundance of Prevotella melaninogenica was negatively correlated with peripheral blood neutrophil ratio and neutrophil to lymphocyte ratio(r = -0.479,P = 0.009;r = -0.555,P = 0.002),while the relative abundance of Streptococcus sanguinis was positively correlated with peripheral blood neutrophil ratio and neutrophil to lymphocyte ratio (r = 0.450,P = 0.014;r = 0.501,P = 0.006).There was also a significant positive correlation between Oribacterium and blood eosinophil counts(r = 0.491,P = 0.007). CONCLUSION: Overall,we analyzed the sputum microbiota of COPD patients with different phenotypes and its relationship with clinical indicators, and explored the relationships between microbiota and inflammation in COPD.We hope to alter the prognosis of patients by inhibiting specific bacterial taxa related to inflammation and using guide individualized treatment in the future research.

Meta-analysis of the efficacy and safety of mirabegron and solifenacin monotherapy for overactive bladder.

AIM: We conducted a meta-analysis to evaluate the safety and efficacy of mirabegron (50 mg) and solifenacin (5 mg) monotherapy for overactive bladder (OAB) during a 12-week cycle. METHODS: Randomized controlled trials (RCTs) of mirabegron and solifenacin for OAB were searched systematically by using MEDLINE, EMBASE, and the Cochrane Controlled Trials Register. The reference lists of retrieved studies were also perused. RESULTS: Five RCTs which compared solifenacin with mirabegron were studied. Mirabegron achieved the same effect as solifenacin in treating OAB. The mean number of incontinence episodes per 24 h (P = 0.20), mean number of micturitions per 24 h (P = 0.11), mean number of urgency episodes per 24 h (P = 0.23), and mean volume voided per micturition (P = 0.05) suggested that mirabegron and solifenacin had no significant differences in terms of OAB treatment. With regard to drug-related treatment-emergent adverse events (DR-TEAEs) and dry mouth, mirabegron showed better tolerance than solifenacin. Post-voiding residual volume showed a distinct difference in the two groups. Hypertension and tachycardia did not show a significant difference between the two groups, but the pulse rate did. CONCLUSION: The therapeutic effect of mirabegron is similar to that of solifenacin, and mirabegron does not increase the risk of adverse events (AEs).