What Is Cystic Fibrosis? Symptoms, Diagnosis and Treatment Methods

Cystic fibrosis (CF) is an inherited, serious and potentially life-threatening disease. It can affect the body’s secretion systems, especially the respiratory tract, pancreas, gastrointestinal system and sweat glands.

Who Gets Cystic Fibrosis?

In our country, one baby with CF is born in every 3,000 births. Since cystic fibrosis is a genetically inherited disease, the disease can occur in the baby only when the disease gene from both the mother and the father comes together.

The mother does not show signs of the disease because one of her two genetic copies is healthy. The father also has the same feature as the mother; one of his two genetic copies is healthy. Such parents are called carriers. The probability of the disease occurring in a child born to carrier parents is 25%.

How Does Cystic Fibrosis Develop?

The genetic defect in patients affects the movement of water and salt through the cell membrane and therefore affects all secretion systems of the body, especially the respiratory tract, pancreas, gastrointestinal system and sweat glands.

Normally, these glands produce thin and fluid secretions. In patients with CF, however, these secretions become thicker and lose their fluidity and purity. Therefore, people with this disease have difficulty bringing up sputum. Problems begin when the small airways become blocked. Coughing, wheezing, pneumonia and bronchitis may occur.

Changes in the content of secreted body fluids allow antimicrobial-resistant microbes to settle more easily in the lungs. This leads to chronic, long-lasting inflammation and long-term damage to the lungs.

Because these secretions cannot be released and blockages occur in the ducts, the secretions cannot flow into the intestines and the nutrients taken in cannot be digested. In patients with CF, the insufficiency of secretions from the pancreas and liver that support digestion and their inability to flow into the intestines mean that food cannot be adequately digested and absorbed.

Large amounts of foul-looking, oily and very foul-smelling stool may occur. The patient may have abdominal bloating and gas. If not treated, the patient may fail to gain enough weight and growth may be delayed.

What Are the Symptoms?

In the newborn period, consanguinity between parents, a history of sibling death, a history of intestinal obstruction, jaundice and a salty taste when kissed; in infancy, growth retardation, large amounts of foul-smelling oily stool, frequently recurrent respiratory tract infections, anemia and edema; and in childhood and adolescence, recurrent wheezing attacks, persistent or recurrent lung infections, thick purulent sputum production, chronic and persistent sinusitis, asthma, childhood-onset diabetes and delayed puberty are among the findings that strongly suggest the disease.

How Is Cystic Fibrosis Diagnosed?

Children’s sweat is saltier than that of others, and families often notice this, especially when they kiss their children. In summer, salt crystals may sometimes be seen on the child’s face or body.

For diagnosis, “measuring the amount of salt in sweat” is important and is one of the most valuable tests. In a very simple and painless way, sweat glands are stimulated with a small device placed on the arm, sweat is collected, and the chloride level in the sweat is measured. This test does not hurt the patient. The chloride level in the sweat of individuals with CF is high. For diagnosis, at least two test results showing high values are needed. Borderline chloride values may be seen in some children with mild disease. Your doctor’s interpretation is important in this regard. If enough sweat cannot be collected, the test may need to be repeated.

After diagnosis, a blood sample is taken from the patient for mutation analysis of the gene. Many mutations have been identified in the gene that causes the disease. The diagnosis can be confirmed when mutations are demonstrated in the genes inherited from both the mother and the father. Failure to detect the screened mutations does not mean that the child is not affected, because the child may carry one of the remaining mutations or a mutation that has not yet been identified. It is also possible to identify mutations genetically through gene sequencing analysis.

Prenatal diagnosis may also be performed if a sibling will be born to a patient known to have CF or if testing of the baby is planned because of similar disease in close relatives. While the baby is in the womb, diagnosis can be made before birth by chorionic villus sampling from the membranes surrounding the baby at the 11th week, or by amniocentesis using a sample from the fluid surrounding the baby at 16–17 weeks. If the baby is found to be affected, the family is provided with genetic counseling by specialist physicians regarding continuation or termination of the pregnancy.

In newborn screening for cystic fibrosis, diagnosis can be made through tests performed on heel-prick blood samples taken from babies during the first week after birth. To confirm the diagnosis, these babies should undergo a sweat test at a later stage.

What Is the Course of the Disease?

While life expectancy for patients with CF used to be shorter in the past, it has increased significantly thanks to early diagnosis, regular follow-up, effective treatment of infections, nutritional support and new disease-targeted treatment options. In the 1960s, life expectancy was much lower; today, many patients reach adulthood and are able to lead active lives.

The course of the disease may vary from person to person depending on the type of genetic mutation, the degree of lung involvement, pancreatic and digestive system involvement, frequency of infections, nutritional status and adherence to treatment.

What Is the Treatment for Cystic Fibrosis?

Although the disease had a fatal course in early years at the beginning of the last century, significant prolongation of survival has been achieved as knowledge about the condition has increased. However, there is still no definitive cure. With early diagnosis and effective treatment methods currently used worldwide, very encouraging results can be obtained in these patients, and they can live enjoyable and active lives. On the other hand, gene therapies are being investigated for a definitive treatment of the disease.

The most important complaints in patients with cystic fibrosis are related to the respiratory system. Respiratory physiotherapy should be performed to clear the sticky sputum caused by chronic inflammation in the airways, and it should be done every day, at least twice a day. If the patient has increased cough and sputum, this practice should be performed at least 3–4 times a day.

In patients with cystic fibrosis, early detection and immediate effective treatment of infections are very important. Especially during periods when cough and sputum increase, appropriate antibiotic treatment should be started orally or, if needed, by hospitalization.

As in every chronic disease, nutrition is very important in patients with cystic fibrosis. Adequate nutrition under the follow-up of a pediatric gastroenterologist, as well as enzyme and necessary vitamin supplementation, is important.

Studies for a definitive treatment of the disease are ongoing. These studies focus on “gene therapy.” Today, many studies are also continuing on new medications that may improve patients’ quality of life and survival.

Frequently Asked Questions

References

1. Cystic Fibrosis Foundation. About Cystic Fibrosis. View source
2. Cystic Fibrosis Foundation. Sweat Test. View source
3. NHLBI, NIH. Cystic Fibrosis Diagnosis. View source
4. NHLBI, NIH. Cystic Fibrosis Treatment. View source