Cystic Fibrosis is an inherited (genetic) disease that affects the exocrine glands. Exocrine glands secrete fluids such as mucus, that are meant to lubricate organs and tissues. An example of this is in the pancreas; the exocrine glands secrete digestive enzymes. Other exocrine glands are found in the lungs, liver, mouth (saliva), and sweat glands. Even tear glands are exocrine glands (I have noticed my son has very large tears that don’t trickle down as easily as everyone else’s). Mucus can clog the tubes that carry sperm from the testes, causing most men with CF to be infertile. In CF, the exocrine glands produce mucus that is thick and sticky. The two main places that get affected by this thick mucus is the airways, and the digestive system.
In a normal person, their lungs produce a thin layer of mucus that is moved out of the lungs by cilia, hair-like fibers that sweep the lungs clean. This helps to remove harmful bacteria out of the airways. In CF, the cilia cannot move the mucus out of the lungs effectively because the mucus is too thick. The mucus is a breeding ground for harmful bacteria to grow. The lungs become inflamed by bacteria, and start to produce even more thick, sticky mucus to get the bacteria out. This can lead to lung infections. Repeated lung infections in CF cause permanent damage to the lungs, causing lung disease, which is the main cause of death from CF.
People with CF can get lung infections very easily. Staphylococcus aureus, otherwise known as Staph, is a common bacteria that can frequently cause lung infections. Pseudomonas aeruginosa and Burkholderia cepacia are two types of bacteria that are difficult to treat with antibiotics and often it is not possible to remove them from the lungs completely, so it is important to control them with periodic antibiotics.
Mucus not only affects the lungs. Occasionally, it can affect the sinuses with sinusitis and nasal polyps. Sinusitis is inflammation of the sinuses, caused by mucus. It is treated with decongestants, antihistamines, and antibiotics. It can also be treated by flushing the sinuses out with saline solution. Nasal polyps are small fleshy growths inside the nose. It is currently not known exactly why this happens. Usually, no treatment is needed, but if they cause interference with breathing, they may need to be surgically removed.
The Digestive System
In 9 out of 10 people with CF, glands in the pancreas produce thick mucus that does not allow pancreatic enzymes to reach the intestines where digestion normally happens. Meals are not digested properly and most of the fat, protein, and fat soluble vitamins are not absorbed into the body. Often in CF, a person is very hungry, and eats well, but does not gain weight because of malabsorption and the extra work required to breathe. Malabsorption causes bulky, greasy stools, excessive gas, and abdominal pain and swelling.
Meconium ileus is an intestinal blockage of a newborn, and about one in 10 baby’s born with CF have meconium that is thick. This needs to be removed either surgically or by a special enema. If a baby is born with meconium ileus, it is tested for Cystic Fibrosis. This blockage can also occur in older people with CF, which is called Distal intestinal obstructive syndrome, caused by poorly digested food. Blockage of the intestines can also happen if a person produces mucus in the intestines that is thick and sticky.
Bronchiectasis - Overtime, repeated inflammation causes damage to the lungs. This damage causes the airways to become stretched and dilated. More bacteria and mucus can become trapped in the airways. Chest therapy and coughing can help clear the dilated areas.
Pneumothorax - is a collection of air outside the walls of the lungs. When there is a tear in the lung tissue, this allows air to escape from the lungs and become trapped in the chest wall. This may cause lung collapse. Medical therapy is needed to let the trapped air out. Sometimes, surgery is needed to prevent this from reoccurring.
Hemoptysis - means to cough up blood from the respiratory tract. This can be caused by mucus causing tearing in the lining of the airways.
Clubbing - is the rounding of the tips of fingers and toes. Mostly all people with CF eventually get this. It is not known exactly why this happens.
Cor Pulmonale - is when the right side of the heart becomes larger and thicker. In CF, because of damage to the lungs, less oxygen is absorbed through the lungs so the heart has to work harder to circulate oxygen through the blood. Lung damage can also increase blood pressure. Prolonged high-blood pressure in the pulmonary artery and right ventricle can also cause cor pulmonale.