Cystic fibrosis is a genetic disorder passed down through families. The disease affects approximately 30,000 adults and children in the United States and more than 70,000 people worldwide. Cystic fibrosis is characterized by a thick, sticky mucus that builds up in the lugs, liver, intestine, digestive tract, pancreas, and other areas of the body. Thick mucus that clogs the lungs may lead to serious or life-threatening infections. Obstructions in the pancreas may prevent natural enzymes that normally break down food from breaking down food to the point where it can be absorbed or even removed by the body.
History of Cystic Fibrosis
The history of cystic fibrosis is a long recognized medical condition, which dates back to the 1930s when pathologist Dr. Dorothy Andersen observed the condition at New York Babies Hospital. Historians note early references of what was likely cystic fibrosis dating back to the 17th century when references were made in children’s songs and games of the day. The name comes from a scarring (fibrosis) and cyst formation that occurs within the pancreas; although other organs are also affected. In the early days of CF, few children with the condition lived to attend elementary school. Today, most children with CF live into adulthood.
Cause of Cystic Fibrosis
A mutation in a gene responsible for a certain protein that regulates mucus, digestive fluids, and sweat is the cause of CF. Healthy individuals have two copies of this particular gene. Since the genetic irregularity that causes CF is recessive in nature, one normal gene will prevent CF from developing. The condition only emerges when both genes have the same irregularity. Since it is a genetic disorder, this mutation is often passed on to future generations within the same family. According to the World Health Organization, when two carries of the gene that causes CF conceive, there is a 25 percent chance that the condition will be passed on to offspring and a 50 percent chance that the child will be a carrier of the gene.
Symptoms of Cystic Fibrosis
Difficulty breathing is one of the most noticeable symptoms of cystic fibrosis. The initial symptom of CF is usually salty tasting skin caused by secretions from the sweat glands. Coughing, shortness of breath, and frequent chest colds are also early signs of cystic fibrosis. Since these symptoms can mimic many other lung disorders and conditions that cause coughing and congestion, a blood test is required to confirm that the genetic disorder exists. Additional symptoms of cystic fibrosis include:
- Poor growth (noticeable height issues in childhood)
- Difficulty breathing (wheezing or shortness of breath)
- Difficulty gaining and maintaining weight even with a normal diet
- Accumulation of sticky, thick mucus
- Frequent coughing (often with phlegm)
- Frequent chest infections
- Shortness of breath
- Poor absorption of nutrients required for normal childhood development
- Bowel obstructions (in newborns)
- Difficulty in bowel movements
Cystic Fibrosis Testing
Diagnosing cystic fibrosis can start before birth if it is known that the mother is carrying the gene for CF. Genetic testing done before birth can detect the gene that indicates CF and whether or not both genes are affected. A sweat test can be performed in early childhood to confirm the condition if it wasn’t diagnosed before birth. Cystic fibrosis testing includes:
- Newborn screening – All states automatically screen newborns for cystic fibrosis with a genetic blood test. The blood test also confirms that the pancreas is functioning.
- Sweat test – If a blood test suggest CF, the next step is to confirm the diagnosis with a sweat test to measure the amount of salt in the body’s sweat. A sweat-producing chemical is applied to a patch of skin to induce sweating; usually on the arm or leg. A sweat test is usually performed twice to confirm the results.
- Genetic testing – If a sweat test indicates CF, genetic testing is usually performed to confirm the location of the CF defect.
- Chest x-ray – A chest x-ray checks the heart, lungs, and blood vessels and checks for signs of scarring and inflammation.
- Sinus x-ray – A sinus x-ray checks for signs of sinusitis, a common symptom of CF.
- Lung function tests – Various tests check lung functioning and determine how much oxygen is being delivered to the blood by the lungs.
- Sputum (spit) culture – Spit is checked for signs of a certain type of bacteria that may indicate an more aggressive form of CF.
- Prenatal screening – Amniocentesis (fluid from the sac around the baby) and chorionic villus sampling (a tissue sample from the placenta) are the most common prenatal screenings that can detect CF in a fetus.
There is no cure for CF, but there are treatments that can reduce the symptoms of the disease. Treatment for CF typically includes proactive treatment of airway infections and a recommended diet consisting of essential nutrients. Treatment is often tailored to the individual since each patient can have different symptoms at different times. Treatments tend to focus on the lungs, gastrointestinal tract, and reproductive system. Additional cystic fibrosis treatments include:
- Medication – Various medications can be prescribed to treat different symptoms of CF. Inhalation medications clear thick mucus.
- Gene therapy – The goal of gene therapy is to introduce normal CFTR (a chloride channel protein normally found in healthy cells) into the airways of the lungs.
- Antibiotics – Most CF patients are on some antibiotics throughout their lifetime, even when healthy and not showing any symptoms related to the condition. Oral antibiotics such as ciprofloxacin are often given to prevent infection or fight an ongoing infection. In some cases, antibiotics must be given by IV during a hospitalization for a certain period of time. The amount of antibiotics given to each patient is often adjusted to prevent side effects from prolonged usage.
- Mucus-thinning drugs – These drugs force mucus to come up from the lungs or thin mucus to make it more manageable.
- Bronchodilators – Bronchodilators relax muscles around the bronchial tubes to keep the airways open.
- Lung transplant – If the condition worsens, a lung transplant may be the only remaining treatment when breathing becomes too difficult and cannot be controlled or remedied with medication.
Cystic fibrosis affects roughly a thousand new patients each year. The majority of CF patients are diagnosed by the age of two. Nearly half of the CF population is over the age of eighteen. The average survival rate of an individual with CF is well into the late thirties. However, there are many reported instances of people diagnosed with CF at birth or early in life living well into old age.