Neutrophilic Asthma Is Associated with Increased Airway Bacterial Burden and Disordered Community Composition

Figure 4

Bacterial phyla in sputum samples from subjects with NA and non-NA. In comparisons of relative abundances (a), differences of Proteobacteria, Firmicutes, Bacteroidetes, and Fusobacteria between groups were determined by using t-test due to their normal distributions, while differences of the other phyla were determined by using Mann–Whiney U test. In comparisons of actual loads (b), differences of all phyla were determined by using Mann–Whitney U test. Correlation coefficients between bacterial phyla and neutrophil percentage were calculated by Spearman’s correlation (c). Significant differences between relative abundances of phyla were shown as < 0.05 and < 0.001. Significant differences between actual loads of phyla were shown as < 0.01. The dots represent all of the values. NA: neutrophilic asthma.

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(b)

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