Cystic Fibrosis: A-to-Z Guide from Diagnosis to Treatment to Prevention

Young boy in and outdoor setting. Could he have cystic fibrosis?

Introduction to cystic fibrosis:

A diagnosis of cystic fibrosis was once assumed to be an early childhood death sentence. As of 2009, the median lifespan was in the mid-30s, according to the CF Foundation Patient Registry. Children with CF attend school normally, graduate from college, and assume their places in the adult world. Still, the shortened lifespan is painfully poignant. But treatment continues to advance rapidly. Those born with CF today may see a dramatically brighter outlook by the time they are 10 or 20 years old.

What is cystic fibrosis?

Cystic fibrosis is an inherited condition where important membrane linings do not function properly. Thickened, rubbery mucus results in blockage and infection throughout the respiratory tract. The pancreatic and bile ducts are blocked, leading to severe digestive problems. Sweat and other secretions contain increased salt.

CF is the major cause of severe chronic lung disease in children. It is also a leading cause of pancreatic problems.

Who gets cystic fibrosis?

CF is inherited as a recessive condition. Both parents must carry the recessive gene and pass the gene to their child in order to result in CF. It can occur in any ethnic group, but it is most common among Caucasians of Northern or Central European ancestry, where, according to the American Lung Association, it affects about 1 in 2500 children.

Why is such a deadly recessive gene so common? Some theorize that carriers of the gene were protected against the ravages of cholera.

What are the symptoms of cystic fibrosis?

CF can cause a wide variety of symptoms in many organ systems.

The most prominent feature of CF is usually chronic problems with the respiratory system. This might include a chronic cough (to attempt to move the thick mucus) especially in the morning or after exertion.

Children with CF might develop severe or frequent bronchiolitis, pneumonia, and/or sinusitis. Wheezing and clubbing of the fingernails are common.

Problems stemming from the GI tract are the next most common feature. This might include difficulty passing stool (especially that first meconium stool); rectal prolapse; large, smelly, greasy stools; and failure to gain weight (even with a large appetite).

Is cystic fibrosis contagious?


How long does cystic fibrosis last?

At present, CF is a lifelong condition with a median survival of about thirty years.

How is cystic fibrosis diagnosed?

CF may be diagnosed on newborn screening tests in some areas. When the diagnosis is suspected, because of family history or classic symptoms, specific testing is done. This might include a sweat chloride test, genetic testing, a nasal membrane test, or a variety of other studies.

Couples who are pregnant or are planning on becoming pregnant may be interested in prenatal genetic testing to determine whether they are carriers of the abnormal CF gene. The test identifies the majority of genetic mutations in the CF gene, but extremely rare mutations may be missed. A sample of blood or mouthwash is sent to the laboratory, and the results are usually ready in 5 to 10 days. If both partners are identified as CF carriers, the pregnant mother may opt to undergo a special procedure called chorionic villus sampling or amniocentesis in order to determine if the unborn baby has inherited the two abnormal CF genes.

How is cystic fibrosis treated?

When possible, CF treatment should be provided by a team of people who specialize in this area. The Cystic Fibrosis Foundation can be helpful in finding such a team (

Typically, a pulmonologist (lung specialist) is the head of such a team. Comprehensive preventive care is important, coupled with aggressive treatment of complications when they inevitably arise. Chest therapy is aimed at keeping the airways hydrated and clear, and treating infections aggressively. Nutritional therapy includes replacing pancreatic digestive enzymes and tailoring the diet and supplements to match the child’s needs.

How can cystic fibrosis be prevented?

At present, the only way to prevent conceiving a child with CF is to avoid two carriers conceiving together.

Related concepts:


Dr. Alan Greene
