Lower respiratory infections are a leading cause of death worldwide. Immediate initiation of correct and adequate treatment is of vital importance to ensure a favourable outcome of disease. However, diagnostics methods for lower respiratory infections are limited, especially when it concerns bacterial pathogens.

Currently, sputum culture is the standard. However, culturing takes at least 24 hours and frequently yields inconclusive results due to low sample quality. Faster and more accurate molecular methods are available. Unfortunately, these are most often unable to extract diagnostically relevant information from the biologically complex matrix sputum.

Besides the complexity of sputum, obtaining a sample is an obstacle as ill patients have respiratory impairment. Especially, in case of patients with underlying chronical respiratory disease, e.g. COPD and cystic fibrosis. The latter category of patients is particularly important as they regularly suffer from lower respiratory infections.