Cystic fibrosis is an inherited disorder that causes severe damage to the lungs, digestive system and other organs in the body.
Cystic fibrosis affects the cells that produce mucus, sweat and digestive juices. These secreted fluids are normally thin and slippery. But in people with cystic fibrosis, a defective gene causes the secretions to become sticky and thick. Instead of acting as a lubricant, the secretions plug up tubes, ducts and passageways, especially in the lungs and pancreas.

Although cystic fibrosis requires daily care, people with the condition are usually able to attend school and work, and often have a better quality of life than people with cystic fibrosis had in previous decades. Improvements in screening and treatments mean people with cystic fibrosis now may live into their mid- to late 30s, on average, and some are living into their 40s and 50s.

Symptoms

Screening of newborns for cystic fibrosis is now performed in every state in the United States. As a result, the condition can be diagnosed within the first month of life, before symptoms develop. For people born before newborn screening was performed, it's important to be aware of the signs and symptoms of cystic fibrosis.

Cystic fibrosis signs and symptoms vary, depending on the severity of the disease. Even in the same person, symptoms may worsen or improve as time passes. Some people may not experience symptoms until adolescence or adulthood.

People with cystic fibrosis have a higher than normal level of salt in their sweat. Parents often can taste the salt when they kiss their children. Most of the other signs and symptoms of cystic fibrosis affect the respiratory system and digestive system. However, adults diagnosed with cystic fibrosis are more likely to have atypical symptoms, such as recurring bouts of inflamed pancreas (pancreatitis), infertility and recurring pneumonia.
Respiratory Signs and Symptoms
The thick and sticky mucus associated with cystic fibrosis clogs the tubes that carry air in and out of your lungs. This can cause signs and symptoms such as:
  • A persistent cough that produces thick mucus (sputum)
  • Wheezing
  • Breathlessness
  • Exercise intolerance
  • Repeated lung infectionsInflamed nasal passages or a stuffy nose
Digestive Signs and Symptoms
The thick mucus can also block tubes that carry digestive enzymes from your pancreas to your small intestine. Without these digestive enzymes, your intestines aren't able to completely absorb the nutrients in the food you eat. The result is often:
  • Foul-smelling, greasy stools
  • Poor weight gain and growth
  • Intestinal blockage, particularly in newborns (meconium ileus)
  • Severe constipation    
Frequent straining while passing stool can cause part of the rectum — the end of the large intestine — to protrude outside the anus (rectal prolapse). When this occurs in children, it may be a sign of cystic fibrosis. Parents should consult a physician knowledgeable about cystic fibrosis. Rectal prolapse in children may sometimes require surgery. Rectal prolapse in children with cystic fibrosis is less common than it was in the past, which may be due to earlier testing, diagnosis and treatment of cystic fibrosis. (MayoClinic)

Risk factors

The only risk factor for getting CF is having two parents who carry abnormal CF genes and pass the abnormal gene to their child. However, there are factors that impact how severe the CF is.
  • Genes: CF gene mutations are divided into classes based on how damaged the CFTR protein function is. Classes I, II, and III are generally more severe causing "classic CF." Classes IV and V are usually milder. Also, other genes called modifier genes can affect a person’s symptoms and outcome.
  • Environment and lifestyle: People with CF need to consume a very large number of calories to maintain weight and grow, which can be difficult to achieve. Physical activity is also important to help keep lungs healthy. People with CF should not smoke or be exposed to secondhand smoke, as it will worsen lung disease. You should also be careful with alcohol intake, and avoid it altogether if you have liver disease.  
  • Age: CF worsens with age. If you have CF, you usually experience a small decline in lung function each year.  (American Lung Association)

Diagnosis

Doctors diagnose cystic fibrosis (CF) based on the results from various tests.

Newborn Screening:
All States screen newborns for CF using a genetic test or a blood test. The genetic test shows whether a newborn has faulty CFTR genes. The blood test shows whether a newborn's pancreas is working properly.

Sweat Test:
If a genetic test or blood test suggests CF, a doctor will confirm the diagnosis using a sweat test. This test is the most useful test for diagnosing CF. A sweat test measures the amount of salt in sweat.

For this test, the doctor triggers sweating on a small patch of skin on an arm or leg. He or she rubs the skin with a sweat-producing chemical and then uses an electrode to provide a mild electrical current. This may cause a tingling or warm feeling.

Sweat is collected on a pad or paper and then analyzed. The sweat test usually is done twice. High salt levels confirm a diagnosis of CF.

Other Tests
If you or your child has CF, your doctor may recommend other tests, such as:

  • Genetic tests to find out what type of CFTR defect is causing your CF.
  • A chest x ray. This test creates pictures of the structures in your chest, such as your heart, lungs, and blood vessels. A chest x ray can show whether your lungs are inflamed or scarred, or whether they trap air.
  • A sinus x ray. This test may show signs of sinusitis, a complication of CF.
  • Lung function tests. These tests measure how much air you can breathe in and out, how fast you can breathe air out, and how well your lungs deliver oxygen to your blood.
  • A sputum culture. For this test, your doctor will take a sample of your sputum (spit) to see whether bacteria are growing in it. If you have bacteria called mucoid Pseudomonas, you may have more advanced CF that needs aggressive treatment.
Prenatal Screening:

If you're pregnant, prenatal genetic tests can show whether your fetus has CF. These tests include amniocentesis (AM-ne-o-sen-TE-sis) and chorionic villus (ko-re-ON-ik VIL-us) sampling (CVS).

In amniocentesis, your doctor inserts a hollow needle through your abdominal wall into your uterus. He or she removes a small amount of fluid from the sac around the baby. The fluid is tested to see whether both of the baby's CFTR genes are normal.

In CVS, your doctor threads a thin tube through the vagina and cervix to the placenta. The doctor removes a tissue sample from the placenta using gentle suction. The sample is tested to see whether the baby has CF.

Cystic Fibrosis Carrier Testing:

People who have one normal CFTR gene and one faulty CFTR gene are CF carriers. CF carriers usually have no symptoms of CF and live normal lives. However, carriers can pass faulty CFTR genes on to their children.

If you have a family history of CF or a partner who has CF (or a family history of it) and you're planning a pregnancy, you may want to find out whether you're a CF carrier.

A genetics counselor can test a blood or saliva sample to find out whether you have a faulty CF gene. This type of testing can detect faulty CF genes in 9 out of 10 cases. 

Treatment

Treating the respiratory tract is very important to prevent or slow down the long-term lung damage from CF.

Airway Clearance Therapy

People with CF need to perform “airway clearance therapy” (ACT). This can be done using manual chest physiotherapy or a device called the "VEST." This jacket shakes the mucus in the airways, enabling you to cough it up. Another portable device is called a "flutter." This causes the mucus in the airways to vibrate or "flutter" when you breathe through the device.

Mucus Thinning Medication

A nebulizer or inhaler is often used before performing ACT. Commonly used medications are albuterol that relaxes the airway and helps mucus to clear, dornase alpha that thins the mucus so that you can cough it up more easily, and hypertonic saline solution that restores moisture and salt to the cell surface in the airway.

Enzymes and Nutrients

Other medications that are very important are pancreatic enzyme replacement therapies. These help the body absorb food and necessary nutrients. Enzymes have to be given before every meal or snack. People with CF also have to take certain vitamins that are absorbed with fat. Additional salt also needs to be provided in formula or in food.

Antibiotics and Antiinflammatories

Antibiotics are frequently needed to treat bacteria that grow in the mucus. These can be given in one of three ways:
  • Orally or by mouth – this is the easiest and cheapest route.
  • By inhalation – this is more expensive but very effective.
  • Intravenously (IV) – this is usually reserved for those who are sicker.
Anti-inflammatory medications have also been found to be helpful in CF. Two medications are currently in use, azithromycin (an antibiotic that’s used as an anti-inflammatory agent in CF), and ibuprofen.

In 2015 a combination medication called Ivacaftor/Lumicaftor was approved for children aged 12 years and older. Subsequently, it was approved for those 6 years and older. This medication helps individuals who carry two genes of the commonest mutation deltaF508 (Class II).

More medications are in clinical trials and expected to be approved in the near future. The medications currently being tested will help those who carry the most common mutation deltaF508 (Class II) and individuals who do not make CFTR protein at all (Class I). 
Please visit the Cystic Fibrosis website for additional information or to make a donation.
Click for Cystic Fibrosis Website
References by America Lung Association, Mayo Clinic, and The National Heart, Lung and Blood Institute,