- Known or suspected severe bronchiectasis, cystic fibrosis, active pulmonary tuberculosis or infection with other mycobacteria or fungi, known bronchial obstruction, a history of post-obstructive pneumonia, other confounding respiratory diseases, such as lung cancer, malignancy metastatic to the lungs, lung abscess, empyema, suspected aspiration pneumonia due to vomiting, or non-bacterial respiratory infection (chronic obstructive pulmonary disease [COPD] is not exclusionary)