Cystic fibrosis is a genetic disorder caused by changes in the cystic fibrosis transmembrane regulator (CFTR) gene, which creates an imbalance in sodium and chloride concentrations in the cells producing secretions in the body, such as mucus and sweat (exocrine glands).
The disease cannot be acquired throughout the lifespan, which means that a person needs to be born with cystic fibrosis to have it. Both the mother and the father necessarily carry the gene affected by this disease, even if they do not have symptoms of cystic fibrosis. The disease will become manifest only when the child inherits the mutations from both parents because then this child will carry two mutant copies of the CFTR gene.
Since cystic fibrosis results in high concentrations of salt in sweat, it is possible to feel a salty taste in the mouth after kissing the skin of someone who has the disease. For this reason, cystic fibrosis is informally called “the salty kiss”.
The consequences of cystic fibrosis include the production of overly thick mucus that is not properly eliminated by the body. The buildup of mucus in body pathways and organs – such as lungs, pancreas, liver, and intestine – causes changes in the function of these organs. In the lungs, this buildup is associated with the appearance of bacteria that cause severe and chronic infections, which leads to pulmonary inflammation and risks for the patient's health.
The most common bacterium in chronic infections in patients with cystic fibrosis is Pseudomonas aeruginosa (Pa), which affects the lungs and airways. The thick mucus in the airways explains the popular name cystic fibrosis had for many years: mucoviscidosis.
According to the Cystic Fibrosis Foundation, approximately 70,000 people in the world live with cystic fibrosis. In Brazil, there are around 3,000 people with the disease, according to the Brazilian Cystic Fibrosis Registry (REBRAFC), but many other patients may not have received adequate diagnosis and treatment.
A cure for cystic fibrosis does not exist yet, but there is currently great investment and ongoing research. Recent advances already allow patients to live longer and with much more quality of life. For that to happen, early diagnosis and adherence to treatment are essential.
Cystic fibrosis can be controlled with treatment. The biggest challenge today in the management of cystic fibrosis is the high burden of treatment, which requires great discipline and many daily hours of dedication from the patients, their family members, and caregivers. When adherence to treatment is poor, the clinical impact and deterioration of the disease may have severe and irreversible consequences. Thus, adherence to treatment is key.
Who may develop cystic fibrosis?
There are nearly 2,700 Brazilians with cystic fibrosis today, and the incidence in Brazil is one in 10,000 live births.
Cystic fibrosis affects both men and women, of all races. Nevertheless, it is more common among White people and less common among Afro-descendants.
Because cystic fibrosis is a hereditary disease, two affected genes need to be inherited so that the disease manifests in a person – necessarily, one from the mother and one from the father. It is worth mentioning that both parents may be healthy and carry the gene without ever manifesting cystic fibrosis, but the child with two affected genes will have the disease.