What Is Cystic Fibrosis?

Cystic fibrosis (CF) is an inherited disease in which the body makes very thick, sticky mucus. The mucus causes problems in the lungs, pancreas, and other organs.

People with cystic fibrosis (pronounced: SIS-tik fye-BROH-sis) get lung infections often. Over time, they have more trouble breathing. They also have digestive problems that make it hard to gain weight.

What Are the Signs & Symptoms of Cystic Fibrosis?

CF can cause symptoms soon after a baby is born. Other kids don't have symptoms until later on.

Symptoms of cystic fibrosis include:

  • lung infections or pneumonia 
  • wheezing
  • coughing with thick mucus (pronounced: MYOO-kus)
  • bulky, greasy bowel movements
  • constipation or diarrhea
  • trouble gaining weight or poor height growth
  • very salty sweat

Some people also might have nasal polyps (small growths of tissue inside the nose), frequent sinus infections, and tiredness.

How Is Cystic Fibrosis Diagnosed?

Doctors do tests on newborns that check for many health conditions, including cystic fibrosis. These find most cases of CF. To confirm the diagnosis, doctors do a painless sweat test. They collect sweat from an area of skin (usually the forearm) to see how much chloride (a chemical in salt) is in it. People with CF have higher levels of chloride.

Most children with CF are diagnosed by the time they're 2 years old. But someone with a mild form may not be diagnosed until they're a teen.

How Is Cystic Fibrosis Treated?

People with CF will have it all their lives. Doctors use different medicines depending on a person's needs. But all people with CF need to:

  • Loosen and clear mucus. There are different ways to do this. The doctor might recommend that the person:
    • get regular exercise
    • use an inhaler or nebulizer
    • do breathing exercises and cough on purpose
    • wear a therapy vest that shakes the chest
    • have chest physical therapy (banging gently on the chest or back)
  • Prevent or fight lung infections. Washing hands well and often, avoiding people who are sick, and staying at least 6 feet away from others with CF can help prevent infections. Taking preventive antibiotics also can help.
  • Take enzymes. Most teens with CF need enzymes to help them digest food and get nutrients from it.
  • Eat a high-calorie diet and take vitamin supplements, when needed.

What Causes Cystic Fibrosis?

Cystic fibrosis is caused by a change (mutation) in the gene that makes cystic fibrosis transmembrane regulator (CFTR) protein. To have CF, a baby must get two copies of the CF gene, one from each parent.

What Happens in Cystic Fibrosis?

In CF, the body makes abnormal CFTR protein or none at all. Without normal CFTR protein, the cells lining the pathways (tubes) inside some organs make thick, sticky mucus rather than the normal thin, watery kind.

Thick mucus can trap bacteria in the lungs, leading to infection, inflammation, and breathing problems. Mucus also can block the path where digestive enzymes flow between the pancreas and the intestines. This makes it hard for a teen to digest food and get the vitamins and nutrients they need from it.

Thick mucus can also affect the liver, the sweat glands, and the reproductive organs.

How Can I Deal With Cystic Fibrosis?

If you have CF, focus on staying as healthy as possible:

  • Follow the treatment plan. Take medicines as directed, eat high-calorie meals and snacks, and follow instructions for clearing chest mucus.
  • Focus on other things. Find pastimes to enjoy, like art, music, reading, or learning to cook. It's important for teens with CF to get exercise, so also look for ways to stay physically active.
  • Turn to the care team. Your CF care team can offer practical tips on living with CF, and information about clinical trials, support groups, and new therapies.
  • Learn all you can about CF. Experts are always working on new treatments to help people with CF have a better quality of life and live longer. Online, turn to resources like the Cystic Fibrosis Foundation website.
  • Take charge of your medical care. Start early to help manage your CF. You can disinfect equipment, refill prescriptions, and schedule doctor visits. Ask the care team about ways you can get ready for things like going to college or getting a job. Learning about cystic fibrosis and its care can help you become a confident adult managing a chronic health condition.
Back to Articles

Related Articles

Cystic Fibrosis: Diet and Nutrition

Besides extra calories, teens with cystic fibrosis have some specific nutritional needs. Find out more.

Read More

Dietary Tips for Teens With Cystic Fibrosis

Teens with cystic fibrosis have some specific nutritional needs. Here's how they can meet those needs.

Read More

Cystic Fibrosis: Sample Menu

This sample meal plan for teens with cystic fibrosis provides a day's worth of meals that add up to about 3,750 calories.

Read More

Dealing With a Health Condition

If you suffer from a chronic illness, you know it can be anything but fun. But you can become better informed and more involved in your care. Here are tips to help you deal.

Read More

Balancing Schoolwork and Hospital Stays

Every student finds it hard to stay on top of schoolwork sometimes. So what happens when you have to miss a lot of school? This article for teens offers tips and advice.

Read More

Fighting Germs

Germs are tiny organisms that can cause disease - and they're so small that they can creep into your system without you noticing. Find out how to protect yourself.

Read More

Germs: Bacteria, Viruses, Fungi, and Protozoa

Germs are tiny organisms that can cause disease - and they're so small that they can creep into your system without you noticing. Find out how to protect yourself.

Read More

Hand Washing: Why It's So Important

Did you know that the most important thing you can do to keep from getting sick is to wash your hands? If you don't wash your hands frequently, you can pick up germs from other sources and then infect yourself.

Read More

Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor. © 1995-2021 KidsHealth®. All rights reserved. Images provided by The Nemours Foundation, iStock, Getty Images, Veer, Shutterstock, and Clipart.com.