Additional Information General Description New Jersey Resources Recommended Web Sites Patient Education PubMED Search

What Is Cystic Fibrosis?

Cystic fibrosis (CF) is an inherited disease of your mucus and sweat glands. It affects mostly your lungs, pancreas, liver, intestines, sinuses, and sex organs.

Normally, mucus is watery. It keeps the linings of certain organs moist and prevents them from drying out or getting infected. But in CF, an abnormal gene causes mucus to become thick and sticky.

The mucus builds up in your lungs and blocks the airways. This makes it easy for bacteria to grow and leads to repeated serious lung infections. Over time, these infections can cause serious damage to your lungs.

The thick, sticky mucus can also block tubes, or ducts, in your pancreas. As a result, digestive enzymes that are produced by your pancreas cannot reach your small intestine. These enzymes help break down the food that you eat. Without them, your intestines cannot absorb fats and proteins fully.

As a result:

• Nutrients leave your body unused, and you can become malnourished.
• Your stools become bulky.
• You may not get enough vitamins A, D, E, and K.
• You may have intestinal gas, a swollen belly, and pain or discomfort.

The abnormal gene also causes your sweat to become extremely salty. As a result, when you perspire, your body loses large amounts of salt. This can upset the balance of minerals in your blood. The imbalance may cause you to have a heat emergency.

CF can also cause infertility (mostly in men).

The symptoms and severity of CF vary from person to person. Some people with CF have serious lung and digestive problems. Other people have more mild disease that doesn't show up until they are adolescents or young adults.

Respiratory failure is the most common cause of death in people with CF.

Until the 1980s, most deaths from CF occurred in children and teenagers. Today, with improved treatments, people with CF live, on average, to be more than 35 years old. Research continues to look for:

• Better treatments
• A cure

Other Names for Cystic Fibrosis

• CF
• Cystic fibrosis of the pancreas
• Fibrocystic disease of the pancreas
• Mucoviscidosis
• Mucoviscidosis of the pancreas
• Pancreas fibrocystic disease
• Pancreatic cystic fibrosis

What Causes Cystic Fibrosis?

Cystic fibrosis (CF) is caused by a defect in a gene called the cystic fibrosis transmembrane conductance regulator (CFTR) gene. This gene makes a protein that controls the movement of salt and water in and out of the cells in your body. In people with CF, the gene does not work effectively. This causes the thick, sticky mucus and very salty sweat that are the main features of CF.

Each of us inherits two CFTR genes, one from each parent.

• Children who inherit an abnormal CFTR gene from each parent will have CF.
• Children who inherit an abnormal CFTR gene from one parent and a normal CFTR gene from the other parent will not have CF. They will be CF carriers.

CF carriers:

• Usually have no symptoms of CF
• Live normal lives
• Can pass the abnormal CFTR gene on to their children

When two CF carriers have a baby, the baby has a:

• One in four chance of inheriting two abnormal CFTR genes and having CF.
• One in four chance of inheriting two normal CFTR genes and not having CF or being a carrier.
• Two in four chance of inheriting one normal CFTR gene and one abnormal CFTR gene. The baby will not have CF but will be a CF carrier like its parents.

Who Is At Risk for Cystic Fibrosis

About 30,000 people in the United States have cystic fibrosis (CF).

• It affects both males and females.
• It affects people from all racial and ethnic groups but is most common among Caucasians whose ancestors came from northern Europe.

CF is one of the most common inherited diseases among Caucasians.

About 1 in every 3,000 babies born in the United States has CF.

CF is also common in:

• Latinos
• Native Americans, especially the Pueblo and Zuni

CF is much less common among:

• African Americans
• Asian Americans

About 12 million Americans are carriers of an abnormal CF gene. Many of them do not know that they are CF carriers.