What is CF, Anyway?

Most people know that Cystic Fibrosis is a lung disease. Indeed, it is a serious lung disease. Most people with CF end up needing at the end stages of the disease. However, it is much more than just a lung disease. Basically, Cystic Fibrosis is an autosomal recessive genetic mutation that affects the exocrine system. CF is caused by a defect at Chromosome 7, the CFTR, which stands for Cystic Fibrosis Transmembrane Conductance Regulator. It affects the chloride channel of every single cell in the body. Normally, the chloride channel opens and closes, as needed. In CF, the chloride channel doesn't open and close, and the chloride isn't able to move in and out of the cells... And where the chloride goes, the fluid follows. Since fluid doesn't flow through the cells properly, people with CF have extremely dehydrated secretions in all of the exocrine glands.

Here's a quick breakdown of some CF facts:

There are over 1800 mutations that have been identified as of this writing. Variations in the mutations are thought to cause more severe disease in some, and milder disease in others. Basically, CF is a very individual disease. Even siblings with the same exact mutation, can have different degrees of illness.

CF is recessive. In fact, both parents must have a copy of a CF gene in order for a child to have it. Each parent donates a gene to their child at conception. When someone is a carrier of CF, that means they have one CF gene, and one normal gene. When both parents are carriers, they have a one in four chance of having a child with two copies of the gene (born with CF), a one in two chance of having a child with one copy of the gene (carrier), and a one in four chance of having a non-carrier child. One in twenty people in the US are carriers of the CF gene. Approximately thirty thousand people in the US have the disease.

Lungs Thick, sticky mucus inside of the lungs causes constant inflammation in the airways. The inflammation causes the lungs to produce more mucus, which normally would be a helpful thing. In CF, the mucus is so dehydrated and thick, that it is difficult to cough out. The mucus sticks to the surface of the airways, and the cilia, which normally help move mucus up and out of the airways, instead become trapped in it. The mucus irritates the lungs more, the lungs make more mucus, and so it is a vicious cycle. Beneath this layer of thick mucus is a perfect breeding ground for all kinds of bacteria. People with CF usually cough a lot, and take a lot of antibiotics to help fight the infections. They also have to do chest physiotherapy two to three times per day, in order to help break the thick sticky mucus up so they can cough it out. Over time, many people with CF become resistant to several antibiotics, and the infections can be more difficult to treat. There are many strains of bacteria that colonize in CF lungs, but Psuedomonas Auringosa is almost always present. Most people with CF end up needing a lung transplant. Top

Sinuses Like the lungs, the sinuses of people with CF become blocked with mucus. The sinuses become inflamed and thickened over time. Quite often, people with CF develop nasal polyps, and surgery is required to remove them.

Ears People with CF tend to get a lot of ear infections. They also take a lot of antibiotics that are ototoxic, and can develop hearing loss as a result.

Pancreas Most people with CF suffer from malabsorption due to the pancreas becoming blocked with thick secretions. Often, babies with CF are born with the pancreas already blocked, while others develop it over a more gradual period of time, eventually becoming pancreatic insufficient. People with CF who have pancreatic insufficiency have to take pancreatic enzymes with meals and snacks. The enzymes can help a great deal, but for many, even with enzymes, they struggle with eating enough to compensate for the malabsorption, even though they may eat quite a lot more than the average person. Malnutrition in people with CF is common, and they often require a feeding tube to get supplemental tube feedings to help get enough calories. Due to the malabsorption, people with CF tend to have very bloated bellies, lots of gas, fatty and foul smelling stools, and lots of stomach pain. Also, CF patients with pancreatic insufficiency have to take specially formulated vitamins A, D, E, and K, in a water miscible form so that they can better absorb them.

Liver Some CF patients end up with very diseased livers. The thickened bile and blocked ducts can eventually damage to the liver and cause cirrhosis. Some CF patients end up requiring a liver transplant before they need a lung transplant. Some patients receive both a lung and liver transplant at the same time.

Gall Bladder Similar to thickened bile in the liver, the gall bladder can also have thickened bile and become clogged, leaving the gall bladder unable to function properly. People with CF often get gall stones and need surgery to have their gall bladder removed. Top

Diabetes Because of the damage to the pancreas due to it being blocked, many people with CF ultimately develop a CF related diabetes, which usually requires treatment with an insulin pump.

Intestines Some babies with CF are born with a condition called meconium ileus, which is a bowel blockage caused by thickened meconium which can't be passed. Babies born with this condition usually need surgery to remove the sections of bowel affected. Additionally, people with CF often develop bowel blockages throughout their lives. When this happens, they take medications to help, but sometimes they have to have surgery.

Heart Cor Pulmonale is a condition that comes from lung disease. The reduced amount of oxygen intake causes the right side of the heart to become thickened and damaged. Some people with CF end up needing a heart transplant, as well as a lung transplant.

Reproductive Tract Something like 98% of men with CF are born without a vasdeferens, due to it being blocked while in utero. Most men with CF are sterile. Women are less affected, but sometimes the cervical mucus is so thick, it blocks the cervix and makes conception difficult or impossible.

Finger Clubbing A large percentage of people with CF develop finger clubbing, which resembles swollen, rounded finger tips. It is thought that this might be due to the lung disease, as people with other types of lung disease often develop clubbing. However, the degree of clubbing doesn't seem to be related to the degree of lung disease.

Salty Sweat There is a German proverb from the 1700s that states, “A child whose forehead tastes like salt when kissed, will soon die.” They did not know about Cystic Fibrosis until the twentieth century, but they knew that salty tasting babies didn't live long. Because people with CF lose so much salt in their sweat, they are more prone to getting dehydrated or suffer from heat exhaustion in warm climate. Some people with CF have so much salt in their sweat, that they develop salt crystals on their skin. Our dog loves to lick Elena's skin. People with CF need to consume more salt, and tend to put salt on everything, including potato chips!

Median Survival Age Thankfully, the development of many new antibiotics and other medications have extended the life of people with CF. Currently, the median age of survival is the late thirties. At the time of my daughter's diagnosis eighteen years ago, it was twenty-nine. In the 1950's, very few children with CF lived beyond the toddler years. I have personally met a man in his seventies who had CF. I also met a couple who lost their six year old just a few years ago, and another family who lost their thirteen year old. Median survival age is just that, an average. As I mentioned before, CF is a very individual disease. Thankfully, we are ever so close to breakthrough treatments that will help people with CF to live longer, more normal lives!

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