Cystic fibrosis

Cystic fibrosis (CF) is a genetic condition caused by faults in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene. Many people carry a faulty copy of the CFTR gene, but you need two copies (one from the mother and one from the father) to be born with cystic fibrosis.

Cystic fibrosis is normally diagnosed at birth through the Newborn Metabolic Screening Programme (the Guthrie Heel Prick Test), usually carried out within 48 hours after birth. Occasionally, CF is not diagnosed until later in childhood or even adulthood.

Cystic fibrosis affects a number of organs in the body. CF causes the body to produce thick, sticky mucus (normal mucus secretions in our bodies are thin and slippery). This thick, sticky mucus clogs the tiny tubes in the lungs, liver, pancreas, and other parts of the body.

Other organs affected include: ears, nose and sinuses, liver function, bones, and joints.

At present, there is no cure for cystic fibrosis, but new medications can restore the function of the CFTR in many patients.

The type and severity of CF symptoms vary from person to person. In some people not identified with CF through newborn screening, there may be health problems that indicate the presence of CF, such as:

• salty-tasting skin
• slow weight gain, failure to thrive, even with a good appetite
• wheezing, coughing, pneumonia
• abnormal bowel movements

These symptoms are not unique to cystic fibrosis, but when many of these symptoms are present, a doctor may want to do a sweat test for CF to obtain a conclusive diagnosis.

Almost everyone with cystic fibrosis will develop lung damage over time. However, when it occurs and how bad it is differs from person to person.

In the lungs, the thick and sticky in people with CF can be difficult to cough up, causing bacteria, viruses and fungus to become trapped in the lungs. This can cause inflammation and infection, which may result in shortness of breath, wheezing, a chronic cough, and repeated chest infections.

Airway clearance techniques are required to help remove this mucus, reducing the chances of infection.

In the digestive system, the thick and sticky mucus reduces or blocks the flow of enzymes from being released from the pancreas to the intestine. Without these digestive enzymes, fats and vitamins from food can’t be absorbed, causing problems with poor weight gain and malnutrition, even though the person may have a good appetite.

Symptoms of malabsorption include poor weight gain, frequent foul-smelling bowel motions, stomach aches, and excessive gas.

A person with CF may need 120 to 150% of the calorie intake of a person without CF.

Enzyme supplements, supplementary feeding (with high-fat/high-calorie oral supplements given through a nasogastric or gastronomy tube), and vitamin replacement all assist with compensating for decreased activity of the pancreas.

In older CF patients, the pancreas may become less active and reduce or stop the production of insulin, resulting in the CF-related diabetes. This rarely occurs in children. CF-related diabetes is treated in much the same way as Type 1 diabetes, but varies between individuals.

Chest physiotherapy and taking pancreatic enzymes and medications are the mainstay treatments for patients with cystic fibrosis.

• Chest physiotherapy: daily or twice daily airway clearance helps to loosen the thick, sticky mucus that builds up in the lungs. Each session can take 20 to 40 minutes, but can take longer if a person is unwell. This helps reduce the number of chest infections people with CF develop.
• Medications: pancreatic enzymes, vitamin and mineral supplements, antibiotics, inhalers (to open up the airways).
• Exercise: helps keep the lungs healthy
• Specialised nutrition: having good nutrition and maintaining a healthy body weight is very important for people with CF, as it improves their quality of life and lifespan. A dietitian will be one of a number of health professionals involved in providing care for people with CF.

New medicines, known as cystic fibrosis modulator therapies help to correct the cause of CF by correcting the malfunctioning cystic fibrosis conductance regulator (CFTR) protein, made by the CFTR gene.

As CF can be caused by more than 2,000 known genetic mutations, each modulator therapy medicine works on either one or a few different CF mutations.

There are three CFTR modulator therapies available in New Zealand:

1. Trikafta
   Trikafta (a triple therapy containing elexacaftor, tezacaftor and ivacaftor) is funded by Pharmac without age restrictions and has Medsafe regulatory approval for use in people with CF aged 2 years and over with specific gene mutations.
   
2. Kalydeco
   Kalydeco (containing ivacaftor) is funded by Pharmac without age restrictions and has Medsafe regulatory approval for use in people with CF from 1 month of age with specific gene mutations.
   
3. Alyftrek
   In April 2026, a new therapy, Alyftrek (a triple therapy containing vanzacaftor, tezacaftor and deutivacaftor) was funded by Pharmac without age restrictions and has Medsafe regulatory approval for use in people with CF aged 6 years and over with specific gene mutations.

For most patients, CFTR modulators significantly improve lung function, body weight, and other symptoms of cystic fibrosis, reducing the likelihood of people being admitted to hospital. They improve quality of life and life expectancy.

• Cystic Fibrosis NZ
• Cystic Fibrosis Australia