Bronchomalacia

Bronchomalacia is a condition in which the bronchial cartilage is weak, producing a malleable airway that collapses during expiration. It is a form of dynamic airway collapse and is distinct from tracheomalacia, which affects the trachea. The term includes both congenital and acquired forms.

Bronchomalacia can be congenital, due to developmental defects of bronchial cartilage, or acquired after prolonged intubation, thoracic surgery, infection, inflammation, or external vascular compression. It may occur alone or with other airway anomalies.

During expiration, weakened bronchial walls collapse, narrowing the airway and causing air trapping and ventilation-perfusion mismatch. Symptoms include chronic cough, wheeze, and recurrent infections; severe cases may cause dyspnea. Infants may worsen with crying.

Diagnosis relies on bronchoscopy and imaging. Flexible bronchoscopy shows dynamic expiratory collapse of affected bronchi, often greater than 50% luminal reduction. Expiratory CT can visualize airway collapse; PFTs may show obstruction.

Management is individualized. Mild cases may require observation, infection treatment, vaccinations, and airway clearance techniques. In severe cases, airway stenting, bronchoplasty, or tracheobronchoplasty may stabilize airways, with supportive care and treatment of associated conditions.

Prognosis varies with severity and associated conditions. Some children improve as cartilaginous structures mature, while adults with secondary bronchomalacia may have chronic symptoms. The condition is relatively uncommon.