20.7 : 嚢胞性線維症：病因

Cystic fibrosis, or CF, is an autosomal recessive disorder resulting from mutations in the cystic fibrosis transmembrane conductance regulator or CFTR gene on chromosome 7.

CF stems from over 2000 mutations within the CFTR gene.

The CFTR protein functions as an ion channel, regulating chloride and sodium ion transport in mucous-producing cells.

The mutations can cause decreased chloride secretion and increased sodium absorption, producing thicker mucus and impacting the respiratory system.

Initially, a CF patient's lungs appear normal, but a cascade effect followed by infection and inflammation leads to mucus plugging within the bronchioles, causing obstructive lung disease.

CF can clinically resemble chronic bronchitis, bronchiectasis, atypical asthma, allergic bronchopulmonary aspergillosis, and infections like Pseudomonas aeruginosa.

Diagnostic screening involves sweat chloride, DNA, and nasal potential difference tests with confirmation through CF-related mutation tests.

Pulmonary function tests are crucial for monitoring the disease progression.