Analysis of sputum flora in patients with acute exacerbation of chronic obstructive pulmonary disease
Objective To analyze the composition and differences of sputum flora in patients with acute exacerbation of chronic obstructive pulmonary disease(AECOPD),AECOPD with asthma,and AECOPD with bronchiectasis and explore key microorganisms that affect the disease severity.Methods Sputum samples were obtained from AECOPD patients(n=l 1),AECOPD patients with bronchiectasis(n=5)and AECOPD patients with asthma(n=5)admitted in our hospital.All the sputum samples were assessed using 16S rDNA sequencing.Biological information was analyzed with Illumina HiSeq 2500 sequencing.Results The sputum flora of AECOPD patients,AECOPD patients with bronchiectasis,and AECOPD patients with asthma were mainly composed of Firmicutes>,Proteobacteria,Haemophilus and Streptococcus.The abund-ance of Firmicutes in AECOPD with asthma was significantly lower than that in AECOPD(Q=0.781,P=0.049),while that of Rothia decreased in the AECOPD with bronchiectasis patients compared with the AECOPD patients(Q=0.693,P=0.008).The difference in sputum flora in AECOPD patients increased when asthma vs bronchiectasis were combined.Haemophilus and Pasteurella increased in patients with severe lung function impairment,and Moraxella increased in pa-tients with mild lung function impairment.Conclusion The composition of sputum microflora is different between AE-COPD and AECOPD with bronchiectasis or AECOPD with asthma,and may affect the GOLD classification.