Cystic Fibrosis

What is cystic fibrosis?

Cystic fibrosis is a life-threatening genetic disease that causes the body to create thick mucous that builds up and obstructs ducts and tubes within the lungs, digestive tract and pancreas. The build-up of mucous can cause severe or fatal infections and digestive issues. It can also affect the sweat glands and male reproductive system.

While cystic fibrosis can occur in people of any race, it is most common among Caucasians of Northern or Central European descent.

Symptoms of cystic fibrosis are dependent on the severity of the disease, but can include:

  • Shortness of breath
  • Frequent lung infections
  • Persistent coughing
  • Wheezing
  • Fatigue
  • Nasal congestion
  • Stomach pain
  • Weight loss
  • Abnormal and foul-smelling stools
  • Constipation
  • Intestinal blockage

As a result of required screening for cystic fibrosis, newborns can now be diagnosed relatively soon after birth before symptoms occur. However, it can be important to recognize early symptoms among infants, which include:

How is cystic fibrosis diagnosed and evaluated?

The most common types of cystic fibrosis testing include taking a blood sample for genetic testing or conducting a sweat test. A sweat test measures the amount of salt in a person’s sweat. High salt presence can signal cystic fibrosis.

The United States now requires screening of newborns for cystic fibrosis through testing blood samples for abnormal levels of pancreatic chemicals called immunoreactive trypsinogen, or IRT. In some cases, pregnant women can have their babies tested before birth through amniocentesis or a biopsy of the placenta, called chorionic villus sampling (CVS). Amniocentesis is the suction of fluid from the amniotic sac (the membrane filled with fluid around a developing embryo/fetus) through the use of a needle inserted through the abdomen. This fluid can then be tested for cystic fibrosis. During CVS, a needle is used to remove a small amount of placental tissue which is then evaluated for cystic fibrosis and other genetic diseases.

If you have been diagnosed with cystic fibrosis, your doctor may evaluate your condition using a stool test, spirometry or sputum culture. In addition, the following imaging tests may be ordered:

  • Chest or abdominal computed tomography (CT) scan: These exams combine special x-ray equipment with sophisticated computers to produce multiple images or pictures, like a bread-slicer, of the inside of the lungs or intestines. These images can help determine the severity of cystic fibrosis by looking at the amount of mucous present as well as looking for dilated airways in the lungs. The test can also look for infection in addition to the changes associated with the disease. See the Safety page for more information about CT.
  • Chest x-ray: This exam uses a small dose of ionizing radiation to produce images to evaluate for dilated airways containing mucous and also to evaluate lung infections that need to be treated with antibiotics. Chest x-rays are also used to periodically observe lung function and changes in patients with cystic fibrosis or rule out other respiratory conditions such as pneumonia or a collapsed lung. See the Safety page for more information about x-rays.
  • Chest or abdominal magnetic resonance imaging (MRI): These imaging exams use a powerful magnetic field, radio frequency pulses and a computer to produce detailed pictures of the lungs and digestive tract. Though the use of MRI is much less common compared to chest x-ray or CT for this disease, the exam can help assess damage caused by cystic fibrosis.
  • Abdominal ultrasound: This imaging test uses a small transducer or probe and ultrasound gel to expose the abdomen to high-frequency sound waves, which produce pictures of the upper abdomen. It evaluates the pancreas, liver, and gallbladder, all of which are affected by cystic fibrosis.
  • CT of the sinuses: This exam combines special x-ray equipment with sophisticated computers to produce multiple images or pictures of the paranasal sinus cavities. It can help identify unilateral nasal polyps, which are common in patients with cystic fibrosis.

How is cystic fibrosis treated?

While there is no cure for cystic fibrosis, your doctor may recommend one or more of the following to help relieve symptoms and improve quality of life:

  • Lifestyle changes such as better nutrition, use of vitamins, increased physical activity, discontinuing the use of tobacco and avoiding second hand smoke.
  • Medications such as antibiotics and inhaled medicines that help open the airways and clear them of mucous and infection.
  • Various chest therapies or airway clearance techniques (ACT) may help to loosen mucous, which makes it easier to cough up sputum and get rid of it from the lungs.
  • In severe cases, surgery may be needed to improve quality of life. These surgeries can include a lung transplant, nasal polyp removal or the introduction of a feeding tube to help absorb proper nutrients.

This page was reviewed on February 12, 2014

Pediatric Content

Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes child-specific content.

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