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Cystic fibrosis is a hereditary genetic disease that produces an alteration in the secretion of mucus and so affects the respiratory and digestive systems.

Cystic fibrosis is a hereditary genetic disease that produces an alteration in the secretion of mucus, affecting multiple body systems, especially the respiratory and digestive systems.

Mucus is a substance that lubricates and protects the surface of the respiratory tract, digestive, and reproductive systems, together with and many other organs and tissues. In cystic fibrosis, it becomes thicker and more viscous, causing difficulties in breathing and lung infections or irritations. It can also prevent the digestive enzymes produced in the pancreas from passing to the intestine. These enzymes are necessary for proper digestion of food, and their lack results in diarrhea, malnutrition, and weight loss. Furthermore, cystic fibrosis can block the reproductive system’s ducts, causing infertility.

Although cystic fibrosis has no cure and used to be a lethal disease in children, the development of palliative treatments in recent decades has made life expectancy nowadays much longer (around 30-40 years). These treatments consist of antibiotics for respiratory infections, respiratory physiotherapy and exercise to improve lung function, good nutrition, and enzyme supplements if pancreatic insufficiency is present. Early diagnosis can improve both life expectancy and quality of life. Gene therapy is also being studied as a possible treatment for cystic fibrosis.

The CFTR gene (Cystic Fibrosis Transmembrane Conductance Regulator) encodes cystic fibrosis transmembrane conductance regulator, which is a protein whose main function is to act as a channel to transport chlorine ions across the cell membrane. The amount of ions and water influence the viscosity of mucus in the body, so when the CFRT transporter does not work properly, a particularly viscous mucus is produced, which causes the symptoms of cystic fibrosis.

The most commonly identified mutation in the CFRT gene is called delta F508, but more than 1,000 different mutations have been identified in patients with cystic fibrosis. This may explain why some symptoms differ between patients.

In Spain, the incidence of cystic fibrosis is estimated to be one case per 3,500 live births. Moreover, one in 30 people are healthy carriers of the disease.

Cystic fibrosis is an autosomal recessive disease, , which means that both parents must pass the defective gene for an individual to suffer from the disease. If an individual inherits one normal and one defective copy of the gene, they will not develop cystic fibrosis but will still be carriers of the disease and have a greater chance of passing it to their offspring.

It is recommended that future parents who have been diagnosed with the disease or have a family history of the disease seek genetic counseling. This can teach them about the risks of transmitting the disease to their offspring and guide them through necessary genetic testing and choose the most appropriate prevention measures.

FQ – Spanish Federation of Cystic Fibrosis

Hospitals and reference centers listed by the Spanish Federation of Cystic Fibrosis:

Cystic Fibrosis Associations in each autonomous community listed by the Spanish Federation of Cystic Fibrosis

Cystic Fibrosis Manuals