July 22, 2015 – Intraalveolar Catecholamines and the Human Lung Microbiome
Respiratory infections are responsible for tremendous mortality and morbidity worldwide. The advent of culture-independent techniques of bacterial identification and the discovery of the lung microbiome have prompted reconsideration of existing models of pneumonia pathogenesis. Multiple studies have demonstrated an in vitro association between catecholamines and growth of select bacteria, including prominent members of the lung microbiome, including Pseudomonas aeruginosa and Streptococcus pneumoniae. A positive-feedback loop involving alveolar inflammation, intraalveolar catecholamines, and the selective growth promotion of pathogens has been posited as a novel mechanism of pneumonia pathogenesis. However, no study has measured intraalveolar catecholamines or determined their association with changes in the lung microbiome.