General description including types, causes, prevalence, signs and symptoms
What is CF?
Cystic Fibrosis (CF) is the most common inherited life-shortening condition affecting Australians. When someone has CF, his or her cells are missing an essential protein so that chloride and sodium can not be properly transported across the cell membrane. This cellular defect affects the body in many significant ways. In the lungs, mucus secretions are thicker, stickier and hard to move. Blockages in the airways trap bacteria, causing repeated lung infections and localised inflammation that eventually produces scarring and irreversible damage to the lungs. Respiratory failure is the major cause of premature death. CF also directly affects the pancreatic and gastrointestinal systems. Around 90% of people with CF need to consume enzyme capsules when eating. This is because the pancreas is unable to produce sufficient enzymes to digest food. Furthermore, thickened secretions block the pancreatic duct, meaning that naturally occurring enzymes can not reach the small intestine to break down food so that nutrients can be absorbed. CF can also affect the sinuses, liver, spleen and reproductive systems. Around 95% of males with CF are sterile as they either do not have or experience shrinkage of the vas deferens (the tubes which carry sperm from the testes to the ejaculatory ducts). However, the existence of sperm in the testes means that many are able to father children using IVF techniques. Women with CF may also have reduced fertility but in most instances can conceive naturally.
How does CF vary?
Both the severity and symptoms of the condition vary greatly between individuals. Some people experience more problems with their lungs, others with their pancreas and digestive system. Typically, they live with mild, moderate or severe lung disease and gastrointestinal problems. People with mild or moderate CF usually appear healthy but this appearance can be misleading as they must adhere to a rigorous health regimen and see specialist consultants. Life expectancy has improved dramatically for all persons with CF since it was first recognised as a specific condition in the 1930’s and infants with CF rarely lived to be toddlers. Today, with early diagnosis, greater understanding of CF, improvements in treatment and better management, people with CF can live successful, happy and fulfilled lives. The median age of survival (half live longer, half die younger) is now 37 years. Many people who have CF live well into their 30’s, 40’s and 50’s.
How do you get CF?
CF is not contagious. It is an inherited, recessive condition that equally affects both males and females. To be born with CF a child must receive a faulty copy of the ‘CFTR gene’ from both parents. A child that receives a faulty copy from one parent and a normal copy from the other is born a ‘carrier’ and will not have CF. Approximately one in every 25 people in the community is a healthy carrier of the faulty gene, equating to around 1 million carriers in Australia. If both parents are carriers then every pregnancy has a one in four chance of producing a child with CF. Accordingly, around one in every 2,500 babies in Australia is born with CF . Since 1989 the National Newborn Screening program has tested all babies born in Victoria for CF. Approximately 3,000 Australians have CF of which more than 600 live in Victoria.
Treatments, including role of specialists, effects of treatments, use of devices, daily routines
People with Cystic Fibrosis (CF) undertake a daily health regime which increases longevity and maximises quality of life. Each person’s regimen is individual and is informed by and agreed with his or her treating consultants. It may include physiotherapy for airway clearance, exercise, attention to specific dietary requirements, nutritional supplementation and medications.
Airway clearance techniques are used daily to help remove the thick secretions in the lungs, to decrease infections and improve air exchange. Inhaled medications are often used to open the airways either by an inhaler or nebuliser. Then a mixture of percussion physiotherapy, vibes and breathing exercises are used to dislodge small mucus plugs in the airways. This usually causes coughing, enabling the person to ‘cough up’ the mucus. Alternatively, breathing into a device such as a PEP mask or flutter device exerts pressure to loosen mucus. Airway clearance is commonly undertaken between 1-4 times daily at home, but may sometimes be needed in the school or workplace environment. Exercise further assists airway clearance by loosening mucus and promoting deep breathing.
Respiratory medications aim to clear thickened secretions, open airways and prevent or control respiratory infections. Medications vary depending on the individual and the severity of his or her CF. Typically they are numerous, time-consuming and vary throughout the year depending on whether the person is experiencing an exacerbation (a worsening of lung condition) or a ‘well’ period. Some common types of medications include:
Bronchodilators – these can induce overactivity, with a fast heartbeat and trembling hands Anti-inflammatory medications Antibiotics Steroids – these can cause mood swings, irritability and an increased appetite These medications may be given orally, intravenously, through metered dose inhalers or in aerosol form using a nebuliser. Intravenous medications may be administered either in hospital or at home.
Enzymes and other supplements
Pancreatic enzyme capsules are supplements and do not pose a risk if accidentally consumed by someone who does not have CF. The capsules contain a combination of several body-friendly enzymes to help digest and absorb nutrients. When these enzymes pass into the stomach they act like the body’s natural enzymes by breaking down the fats, protein and starch contained in food and increasing absorption in the small intestine. Most people with CF must take enzymes when eating foods and may consume as many as 40 capsules each day. Young children with CF who are unable to swallow capsules consume the enzyme beads from opened capsules mixed together with a pureed fruit such as apple. Additional dietary supplements such as vitamins and calcium tablets may also be taken. Daily salt supplements may also need to be taken as people with CF lose a particularly high level of salt through their sweat. This increases their risk of dehydration and electrolyte imbalance. Alternatively, salty foods may be eaten.
People with CF are encouraged to consume a diet that is high in salt, protein, fats and calories to help provide their high-energy requirement and meet nutritional needs. In general they require an energy intake of between 120% – 150% of the recommended daily allowance (RDA). This may mean consuming large meals and additional snacks throughout the day to maintain proper nutrition. Some people with CF have a gastrostomy tube to help with severe malnutrition. This is a feeding tube that goes directly through the abdominal wall into the stomach. A plastic button sits on the outside of the abdomen. Supplemental liquid nourishment and some medications can be administered through this button. This is rarely undertaken in the school or work environment.