What Is Cystic Fibrosis?
Last updated: November 2020
Cystic fibrosis is a chronic lung disease. It’s a completely different disease. But it presents very similar to COPD. Here’s all you need to know about cystic fibrosis.
What is cystic fibrosis?
CF has existed probably since the beginning of human existence. The disease was alluded to by ancient physicians. And, during the 18th century, a common saying among the medical profession was: “Woe to that child which when kissed on the forehead tastes salty. He is bewitched and soon must die.”
The disease alluded to here was not described for the medical community until 1933. Here, the disease was described as being associated with vitamin A deficiency. It was diagnosed in infancy. It meant the child would probably die within six months. And the cause of death would be a severe respiratory infection. In 1938, the disease was described once again. This time it was given a name: “cystic fibrosis.”1-2
Since that time, much has been learned about it. We now know it’s caused by a defective gene. The gene now has a name: cystic fibrosis transmembrane regulator protein (CTFR). A flaw in this gene causes cells to make mucus that is too thick and sticky. So, rather than lubricating tubes, ducts, and passages inside the body, it tends to get stuck and plugs them.3-5
Sticky mucus clogs ducts. This happens inside the pancreas. Thick and sticky mucus is hard to move to your upper airway. This causes it to remain inside airways. This creates a breeding ground for respiratory viruses and bacteria to grow. It increases the risk of severe respiratory infections. These are what usually cause death for those diagnosed with CF.1-6
How is CF similar to COPD?
Like COPD, CF is a chronic obstructive lung disease that progress over time. Yet, while CF is usually diagnosed early in life, COPD is usually not diagnosed until after the age of 40. Also similar is that people living with both diseases are living better and longer than ever before. People are now living with CF well into their 40s and 50s.6-7
Like COPD, the main organ affected is the lungs. Also like COPD, other organs are also affected. It also affects the pancreas. When it’s ducts are blocked, digestive enzymes don’t make it to the intestinal tract. And this causes digestive problems.1,3,5
They have trouble digesting and absorbing nutrients from the foods they eat. This is especially true with fat, and vitamins A, D, E, and K. So this makes it difficult to maintain a healthy weight. They tend to have "growth failure." This may also increase the risk of developing diabetes later in life. Some people with COPD also develop diabetes.1,3
People living with CF may also experience problems with their liver, sex organs, and skin. They also may experience problems with their heart, such as cor pulmonale. This is another thing in common with COPD. The heart has to work extra hard to pump blood through diseased lungs. This extra work makes the heart abnormally large (hypertrophied). This can lead to other heart problems.3,5
Sweat glands in people living with CF have extra chloride, sodium, and potassium. This is what makes it salty to the taste. In 1959 a sweat test was developed to definitively diagnose CF. Today, there are four tests that definitively diagnose the disease, including genetic testing.1,3,5
There is one type of COPD that is also diagnosed by genetic testing. This is a rare type called Alpha-1 Antitrypsin Deficiency. Other than that one type, there is no one specific test for diagnosing COPD. However, a test called pulmonary function test (PFT) showing airflow limitation is now considered the best test for diagnosing COPD.
Longer and better lives
With COPD, the immune system responds to noxious substances that are inhaled. These chemicals cause airway inflammation. Over time, these chemicals are damaging to lung tissues and cause airway scarring. Mucus has a hard time moving to the upper airway. So, it becomes trapped in the lungs. Both of these effects make airways chronically narrow and obstructed.
With CF, airways are affected by another disease called bronchiectasis. The disease causes tissues lining airways to become chronically dilated and scarred. The mucus becomes thick and sticky. It has a hard time moving to the upper airway. This mucus obstructs airways.
So, both diseases cause obstructed airways. These obstructions slow the flow of air through them, or airflow limitation. The extent of airflow limitation can be determined by performing a PFT. This test can be helpful for diagnosing COPD. However, with both diseases, it can prove helpful for determining the severity of lung disease.
Airflow limitation causes shortness of breath. Trapped mucus may cause coughing. These are the two most common symptoms for both CF and COPD. Other common symptoms include chest tightness and wheezing. Along with these, CF patients may also cough up thick sputum that may appear to be chunky. It may also be of many colors, including green or bloody.
Some of these symptoms may be present on good days. But, both CF and COPD are prone to causing exacerbations or flare-ups. This is when symptoms suddenly get worse. A common cause of flare-ups for both diseases are respiratory infections.
Both diseases may benefit from mucus clearing strategies. Both diseases may also cause low oxygen levels. So, people living with both diseases may benefit from supplemental oxygen. This can help maintain normal oxygen levels. So this is one more thing both diseases have in common.
People living with CF and COPD are both living better and longer than ever before
So, as you can see, CF and COPD are similar in many ways. People with CF are living well into adulthood. Plus, some even go undiagnosed until adulthood. A flare-up may cause them to seek medical attention for symptoms of shortness of breath and coughing. This is why many doctors may also want to rule out CF in those who present in such a way. Such improved diagnostic testing, and improved wisdom and medicine for both diseases have greatly benefited those living with both diseases. This means that people living with both CF and COPD are living better and longer than ever before.
Do you know the difference between a COPD exacerbation and lung function decline?
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