Snapshot A 68-year-old man presents to his primary care physician for a cough. He has been coughing for the past 2 months and is associated with mucopurulent and tenacious sputum production, which has progressively worsened. Medical history is significant for chronic obstructive pulmonary disease. He smokes 1 pack of cigarettes daily for the past 45 years. On physical exam, the patient has wheezes and crackles bilaterally to auscultation. A radiograph of the chest is unremarkable; however, a CT scan of the chest demonstrates stigmata of bronchial dilatation. Introduction Definition a suppurative lung disease that leads to irreversible dilation of the bronchi Etiology Mycobacterium avium complex pulmonary infection Allergic bronchopulmonary aspergillosis Idiopathic Autoimmune disease (e.g., rheumatoid arthritis, systemic lupus erythematosus, and ulcerative colitis) α1-antitrypsin deficiency Immunodeficiency (e.g., HIV and lymphoma) Cystic fibrosis Smoking and chronic obstructive pulmonary disease Pathogenesis conditions that lead to the persistent presence of bacteria in the airway (e.g., immunodeficiency and impaired mucus clearance) cause a host-mediated inflammatory response, which in turn, significantly damages the airway this continues the persistent presence of bacteria and chronic inflammatory response ("the vicious cycle hypothesis") Presentation Symptoms persistent productive cough production of thick sputum Physical exam wheezes and crackles Imaging Chest CT indication imaging modality of choice for confirming the diagnosis findings airway dilation ("tram tracks" and "signet-ring sign") Differential Pneumonia differentiating factor chest imaging will demonstrate a pulmonary infiltrate DIAGNOSIS Making the diagnosis based on the clinical picture that is supported by chest CT findings Treatment Conservative airway clearance techniques indication to improve secretion clearance and bronchial hygiene this decreases the amount of bacteria in the airway in order to decrease the risk of developing another infection examples mucolytics bronchodilators chest physiotherapy (e.g., postural drainage) Medical antibiotics indication to treat the underlying infection in acute exacerbations Complication Antibiotic resistance due to recurrent antibiotic use Hemoptysis due to superficial mucosal vessel injury secondary to recurrent infections