Cystic fibrosis

Cystic fybrosis is caused by a mutation in a gene called the cystic fibrosis transmembrane conductance regulator (CFTR), which helps create sweat, digestive juices and mucous. Although most people without CF have two working copies of the CFTR gene, only one gene is needed to prevent cystic fibrosis. CF develops when neither gene works normally.

In the lungs, the thick mucous accumulates and traps organisms leading to recurrent infections and breathing difficulties. There are many ways the lungs can be affected – all leading to chronic, debilitating lung disease and eventual respiratory failure and death.

In the pancreas, mucous blocks the tiny ducts of the pancreas, resulting in malabsorption of fats, which can lead to diabetes. With this blockage, food including vitamins is not properly digested and malnutrition results.

Repeated infections and blockages can also cause irreversible lung damage and even death.
The sweat glands are also affected and the body may lose an excessive amount of salt during exercise or hot weather.

According to the South African Cystic Fibrosis Association, prevalence of CF is very high among Caucasians. In South Africa, 1 in 27 individuals in the white population, 1 in 50 in the coloured population and at least 1 in 90 in the black population carriers a CF mutation. The total is increasing as more children are correctly diagnosed, treated earlier and living much longer.

Sufferers have an average lifespan of 30 years.

What are its symptoms?

Cystic fibrosis symptoms vary depending on the severity of the disease. In some children, symptoms begin during infancy. Other people may not experience symptoms until adolescence or adulthood.

Early symptoms of CF are often very similar to other childhood problems, which means it may go undiagnosed or even misdiagnosed.

Early symptoms (infancy and early childhood) include:

  • Persistent cough with thick mucous
  • Recurring pneumonia
  • Difficulty breathing
  • Excessive appetite
  • Weight loss
  • Bowel disturbances
  • Extremely salty tasting skin
  • Excessive sweating with a very high salt content
  • Small salt crystals forming on the scalp

Later symptoms (later childhood /adolescents/ adults):

  • Clubbing (enlargement) of the fingertips
  • Persistent chest symptoms
  • Uncontrolled “asthma
  • Bronchiectasis (a condition where the lungs’ airways are abnormally stretched and widened and thus permanently enlarged and constantly producing sputum)
  • Male infertility
  • Sinusitis/nasal polyposis

How is it diagnosed?

CF is usually diagnosed through screening, but some babies and older children (and even adults) are diagnosed after an unexplained illness.

There are three main types of screening for cystic fibrosis:

  • Newborn screening: This involves a heel-prick sample of blood, taken as part of the normal Guthrie test carried out on all children.
  • Carrier testing: A simple mouthwash test can determine if you are a carrier of the defective gene that causes CF.
  • Antenatal testing: Used early in pregnancy, this test is usually offered to mothers who are seen as being at a high risk of having a child with cystic fibrosis.
  • Other tests include a sweat test or a genetic test, where a swab is rubbed gently on the inside of the cheek to look for the faulty gene.

What are your treatment options?

Cystic fibrosis treatment is focused on specialised care to help people live longer, healthier lives.

Treatment options include:

  • Physiotherapy/airway clearance techniques
  • Drugs
  • Lung transplant
  • Exercise

After diagnosis, a treatment plan is developed based on a person’s specific health problems. Following this plan will help a person live a longer, healthier life.

In severe cases of CF, when the lungs stop working properly and all medical treatments have failed to help, a lung transplant may be recommended.

Home treatment is also very important. This includes:

  • Not smoking
  • Using airway clearance techniques (postural drainage and chest percussion)
  • Eating nutritious, high-kilojoule foods
  • Exercising
  • Drinking plenty of fluids
  • Adding salt to foods, especially during hot weather
  • Getting all recommended vaccines and practising good hygiene
  • Management of diabetes if it develops
  • Where the pancreas is affected, pancreatic enzyme replacement will be needed.

Can it be prevented?

As CF is a genetic disorder, it is not preventable. If you or your partner has close relatives with cystic fibrosis, genetic testing before having children may be an option.

If you're already pregnant and the genetic test shows your baby may be at risk of cystic fibrosis, your doctor can conduct additional tests on your developing child.

There are psychological implications around genetic testing. A counsellor will be able to offer advice and support.

For more info
The South African Cystic Fibrosis Association
South African Cystic Fibrosis Trust

The accuracy of this information was checked and approved by physician Dr Thomas Blake in June 2015