Cystic Fibrosis

Cystic fibrosis (CF) is an inherited disease of the glands that make mucus and sweat. People with CF get a defective gene from both parents. People who have one defective gene from one parent are called carriers. They don't have the disease.

CF is a long-term (chronic) disease that gets worse over time. It is a life-threatening condition. But better treatments have made it possible for people with this disease to live longer lives. Most people with CF live into their late 30s, and many even into their 50s or longer. Some people with CF now live into their 70s. 

CF affects a cell protein called CFTR (cystic fibrosis transmembrane conductance regulator). CFTR controls the flow of water and certain salts in and out of the body's cells. As the movement of salt and water in and out of cells is changed, the mucus that many cells normally make gets thicker. This thicker mucus can affect many organs and body systems including:

Respiratory.This includes sinuses and lungs.

Digestive. This includes pancreas, liver, gallbladder, and intestines.

Reproductive. Both men and women may have reproductive problems.

Sweat glands. CF makes sweat very salty. When people with CF sweat, they lose large amounts of salt. This upsets their body’s mineral balance and leads to other health problems.

People with CF can have a variety of symptoms, including:

Very salty-tasting skin

Persistent coughing, at times with phlegm

Frequent lung infections including pneumonia or bronchitis

Wheezing or shortness of breath

Poor growth or weight gain in spite of a good appetite

Frequent greasy, bulky stools or difficulty with bowel movements

Nasal polyps

Chronic sinus infections

Clubbing or enlargement of the fingertips and toes

Rectal prolapse

Very salty-tasting skin.

Persistent coughing, at times with phlegm.

Frequent lung infections including pneumonia or bronchitis.

Wheezing or shortness of breath.

Poor growth or weight gain in spite of a good appetite.

It's an inherited disease caused by a defective gene that can be passed from generation to generation. Cystic fibrosis affects the cells that produce mucus, sweat and digestive juices. These secreted fluids are normally thin and slippery. But in people with CF, they're thick and sticky.If the CFTR gene doesn't work the way it should, a sticky mucus builds up in your body. To get CF, you have to inherit the mutated copy of the gene from both of your parents. Ninety percent of those with affected have at least one copy of the F508del mutation.

The greatest risk factor for cystic fibrosis is a family history of the disease, especially if either parent is a known carrier. The gene that causes cystic fibrosis is recessive. This means that in order to have cystic fibrosis, children must inherit two copies of the gene, one from each parent.

Complications of cystic fibrosis can affect the respiratory, digestive and reproductive systems, as well as other organs.

Respiratory system complications

Damaged airways (bronchiectasis). Cystic fibrosis is one of the leading causes of bronchiectasis, a chronic lung condition with abnormal widening and scarring of the airways (bronchial tubes). This makes it harder to move air in and out of the lungs and clear mucus from the bronchial tubes.

Chronic infections. Thick mucus in the lungs and sinuses provides an ideal breeding ground for bacteria and fungi. People with cystic fibrosis may often have sinus infections, bronchitis or pneumonia. Infection with bacteria that is resistant to antibiotics and difficult to treat is common.

Growths in the nose (nasal polyps). Because the lining inside the nose is inflamed and swollen, it can develop soft, fleshy growths (polyps).

Coughing up blood (hemoptysis). Bronchiectasis can occur next to blood vessels in the lungs. The combination of airway damage and infection can result in coughing up blood. Often this is only a small amount of blood, but it can also be life-threatening.

Pneumothorax. In this condition, air leaks into the space that separates the lungs from the chest wall, and part or all of a lung collapses. This is more common in adults with cystic fibrosis. Pneumothorax can cause sudden chest pain and breathlessness. People often feel a bubbling sensation in the chest.

Respiratory failure. Over time, cystic fibrosis can damage lung tissue so badly that it no longer works. Lung function usually worsens gradually, and it eventually can become life-threatening. Respiratory failure is the most common cause of death.

Acute exacerbations. People with cystic fibrosis may experience worsening of their respiratory symptoms, such as coughing with more mucus and shortness of breath. This is called an acute exacerbation and requires treatment with antibiotics. Sometimes treatment can be provided at home, but hospitalization may be needed. Decreased energy and weight loss also are common during exacerbations.

Digestive system complications

Nutritional deficiencies. Thick mucus can block the tubes that carry digestive enzymes from your pancreas to your intestines. Without these enzymes, your body can't absorb protein, fats or fat-soluble vitamins, so you can't get enough nutrients. This can result in delayed growth, weight loss or inflammation of the pancreas.

Diabetes. The pancreas produces insulin, which your body needs to use sugar. Cystic fibrosis increases the risk of diabetes. About 20% of teenagers and 40% to 50% of adults with CF develop diabetes.

Liver disease. The tube that carries bile from your liver and gallbladder to your small intestine may become blocked and inflamed. This can lead to liver problems, such as jaundice, fatty liver disease and cirrhosis — and sometimes gallstones.

Intestinal obstruction. Intestinal blockage can happen to people with cystic fibrosis at all ages. Intussusception, a condition in which a segment of the intestine slides inside an adjacent section of the intestine like a collapsible telescope, also can occur.

Distal intestinal obstruction syndrome (DIOS). DIOS is partial or complete obstruction where the small intestine meets the large intestine. DIOS requires urgent treatment.

Reproductive system complications

Infertility in men. Almost all men with cystic fibrosis are infertile because the tube that connects the testes and prostate gland (vas deferens) is either blocked with mucus or missing entirely. Certain fertility treatments and surgical procedures sometimes make it possible for men with CF to become biological fathers.

Reduced fertility in women. Although women with cystic fibrosis may be less fertile than other women, it's possible for them to conceive and to have successful pregnancies. Still, pregnancy can worsen the signs and symptoms of CF, so be sure to discuss the possible risks with your doctor.

Other complications

Thinning of the bones (osteoporosis). People with cystic fibrosis are at higher risk of developing a dangerous thinning of bones. They may also experience joint pain, arthritis and muscle pain.

Electrolyte imbalances and dehydration. Because people with cystic fibrosis have saltier sweat, the balance of minerals in their blood may be upset. This makes them prone to dehydration, especially with exercise or in hot weather. Signs and symptoms include increased heart rate, fatigue, weakness and low blood pressure.

Mental health problems. Dealing with a chronic illness that has no cure may cause fear, depression and anxiety.

Since CF is a genetic disease, the only way to prevent or cure it would be with gene therapy at an early age. Ideally, gene therapy could repair or replace the defective gene. Another option for treatment would be to give a person with CF the active form of the protein product that is scarce or missing. preventing CF is not possible. In babies with two abnor mal CF genes, the disease is already present at birth in some organs, such as the pancreas and liver, but develops only after birth in the lungs. Someday, gene therapy may be used to prevent the lung disease from developing.