What is cystic fibrosis?

Cystic fibrosis (CF) is a genetic disease that causes a buildup of mucus in the body. The gene affected by CF controls your body’s production of mucus, digestive fluids and sweat. The CF mutation makes all of these body fluids much thicker than usual, which disrupts a lot of normal bodily processes.

In the lungs, the thickened mucus can trap germs, leading to frequent infections. In the pancreas, mucus blocks digestive enzymes from being released, which keeps the body from absorbing nutrients from food. Not being able to absorb nutrients can lead to vitamin deficiencies and other health problems. This thick mucus can also slow down the digestive system, causing constipation and intestinal blockage.

Symptoms of cystic fibrosis

Cystic fibrosis is usually diagnosed in children, even in infants, but it can sometimes go undetected until the teenage years or even adulthood. Often, the first sign of cystic fibrosis is that babies or young children who have healthy appetites are still small and underweight for their age.

Common symptoms of cystic fibrosis include:

  • Frequent lung infections, which can include bronchitis and pneumonia
  • Persistent coughing, which may or may not include phlegm
  • Nasal congestion and sinus problems
  • Problems with bowel movements
  • Greasy or oily-looking bowel movements
  • Being underweight or having stunted growth, even with a good appetite
  • Salty-tasting skin

As people with cystic fibrosis get older, the disease can also cause problems with fertility.

Diagnosis and testing for cystic fibrosis

If you think your child might have cystic fibrosis, a few tests can help you know for sure. These include:

  • Sweat testing. During this test, a medicine that stimulates sweating is applied to the skin. The sweat is then checked for levels of sodium and chloride, which are higher in the sweat of people with cystic fibrosis.
  • Genetic testing. Using a cheek swab or a small blood, hair or skin sample, your child’s genes can be checked to see if the mutation that causes cystic fibrosis is present.
  • With prenatal genetic testing, you can find out whether your child will have cystic fibrosis before he or she is even born. This may involve taking a sample of amniotic fluid or testing a small sample from the placenta.

Cystic fibrosis treatment options

The severity of cystic fibrosis can vary from person to person, so treatment is tailored to control each person’s unique symptoms. Common treatments include:

  • Clearing the airways of mucus – This might involve wearing a special, inflatable vest that vibrates to shake mucus loose from the lungs, or it might mean using physical therapy or respiratory therapy techniques to clear mucus. Parents, caregivers or therapists might need to help.
  • Inhaling medicines – These can include medicines to prevent lung infections and/or medicines that help keep the airways clear. Medicines are vaporized and inhaled through a nebulizer.
  • Taking pancreatic enzyme supplements – Taken with every meal or snack, these help people with CF absorb nutrients more effectively from their food. People with CF also often take multivitamins to add more nutrients to their diets.

People with CF will need to follow up with their doctors regularly to get their lungs checked and to check for vitamin deficiencies or other health problems. Over time, some people with cystic fibrosis may need a lung transplant. Researchers are working on new ways to treat and cure cystic fibrosis.



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