Sputum Bacterial Spectrum and Predominant Inflammatory Cells in Acute Exacerbations of COPD

This study was done to observe variation with seasons in sputum bacterial profile and predominant inflammatory <br> cells in patients with AECOPD. Hundred sputum samples were cultured for bacteria and examined for type of <br> inflammatory cells. Predominant bacteria and inflammatory cells and their variation with seasons were noted. Thirty six <br> percent of sputum samples had bacterial growth. Bacterial growth was higher in summer and monsoon (43.3%) than in <br> post- monsoon and winter period (21.2%) (p=0.031). Overall, Pseudomonas aeruginosa was the commonest organism <br> cultured. In summer and post-monsoon, the commonest bacterium was Pseudomonas aeruginosa (16.6% and 15.4% <br> respectively) and in monsoon, it was Klebsiella species (19.3%). Sputum neutrophilia (N&gt;61%) was seen in 91% and <br> sputum eosinophilia (E&gt;3%) in 41% of the samples. There was no significant difference in the predominant <br> inflammatory cells (N and N+ E) in sputum with seasons. Isolated sputum eosinophilia was higher in post- monsoon and <br> winter than in summer and monsoon (12.1% v/s 7.5%, p=0.021). Length of hospital stay was less in patients with sputum <br> eosinophilia than in patients with sputum neutrophilia (9.11v/s 10.12 days, p=0.023). Sputum neutrophilia was <br> associated with higher sputum bacterial isolation. Eosinophilia in the sputum was likely to be associated with a sterile <br> sputum. Bacterial isolation was higher in summer and monsoon than post- monsoon and winter. There was no significant <br> difference in the predominant inflammatory cells with seasons. Sputum eosinophilia was associated with faster <br> recovery from AECOPD than sputum neutrophilia.