Bacterial species in sputum specimens were identified accordingly to the North-American guidelines [29] . Sputum samples were directly spread-out in selective media, such as MacConkey agar for Pseudomonas aeruginosa and Alcaligenes xilosoxidans, manitol salt agar for Staphylococcus aureus, and BCSA for Burkholderia cepacia complex, and incubated at + 36 ± 1°C for a period of 18-72 h. Colonies were quantified and identified by classical (manual) phenotypical tests.