Cystic Fibrosis

Cystic Fibrosis
Cystic fibrosis (CF) ...
... is an ‘autosomal recessive’ genetic disorder, meaning that both parents must carry and pass on the recessive defective CF gene. The defective gene normally codes for the production of the CFTR protein – cystic fibrosis transmembrane conductance regulator. This protein is normally found in the secreting epithelial cells of the lungs, pancreas, liver and sweat glands. The protein acts as a chloride ion channel, expelling chloride ions from the cell into the secretions. This lowers the water potential of the secretions and causes water to enter by osmosis. Without this protein the secretions become thick and sticky.
The lungs:
Mucus plays a huge role in the lungs. The mucus normally traps any bacteria in the lungs and the cilia move the mucus out of the lungs, removing the bacteria. In CF, the mucus is too sticky and thick to be removed by the cilia, so the bacteria remain in the lungs and can cause an infection. This is why sufferers of CF are prone to lung infections. CF sufferers are also prone to chronic coughing and coughing up green sputum which is viscous and pus filled. The pus is present as it is an immune response to any bacteria in the mucus.
The pancreas...
...is very important in digestion, producing digestive enzymes and insulin. The thick sticky mucus in CF blocks the ducts in the pancreas; this means that the digestive enzymes don’t reach the intestines resulting in the loss of ability to digest nutrients properly. This can lead to malnutrition, weight loss and poor growth. Because the mucus also blocks the ducts that carry insulin, this can cause diabetes.

Types;
There are over 1,400 identified mutations of the CFTR gene; any mutation, no matter how slight or severe causes CF of varying degrees. Obviously, the more severe the mutation the more severe CF will be.

Treatments ;
There is no cure for CF, but the condition is treated to improve quality and length of life. Treatments include:
• Antibiotics – to combat the frequent lung infections,
• Bronchodilators and Steroids – to reduce lung inflammation and open up airways,
• Insulin and pancreatic enzymes – to aid digestion and treat diabetes
• Diet – a high energy, high protein diet along with vitamin supplements to prevent malnutrition