What is a common characteristic of cystic fibrosis pathophysiology?

A common characteristic of cystic fibrosis pathophysiology is the mutation of the CFTR gene. Cystic fibrosis is primarily caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, which encodes a protein responsible for regulating the movement of chloride ions across epithelial cell membranes. This leads to the production of thick, sticky mucus in various organs, particularly the lungs and pancreas. The impaired ion transport disrupts normal fluid secretion, resulting in airway obstruction and chronic respiratory infections.

Other options describe changes that may occur due to the disease rather than being a defining characteristic of its pathophysiology. For instance, increased lung volume, excessive airway clearance, and a hyperactive immune response could be consequences of living with cystic fibrosis and the body's attempts to cope with the disease but are not fundamental to the initiation of the condition itself. The mutation of the CFTR gene serves as the underlying cause, which distinctly defines the disease.