Cystic Fibrosis – Causes, Diagnosis and Treatment.

Definition

Cystic fibrosis is a life-threatening hereditary disease that causes the body to produce thick and sticky mucus that can clog the lungs and obstruct the pancreas. Over time, mucus builds up inside your airways. This makes breathing a struggle. The mucus traps germs and leads to infections. It can also cause severe lung damage like cysts (fluid-filled sacs) and fibrosis (scar tissue). That’s how cystic fibrosis got its name.

 

Cystic fibrosis

History of Cystic Fibrosis 

• Cystic fibrosis (CF) was first recognized over 400 years ago in Germany and is the most common autosomal recessive disorder in Caucasians.
• In 1938, the American pathologist Dr. Dorothy Anderson provided the first description of the disorder in the medical literature, calling the disease “cystic fibrosis of the pancreas” based on her autopsy findings of children that died of malnutrition. Other physicians of the era referred to the disease as “mucoviscidosis”, which called attention to the presence of thickened mucus.
• In 1989 the responsible gene (CFTR) was identified and its genetic code was sequenced. With each decade, new therapies have been introduced, leading to a dramatic increase in survival.

Prevalence in worldwide

Cystic fibrosis (CF) is a common autosomal recessive disorder affecting approximately 70,000 people worldwide. The majority of people with CF are of Caucasian descent, therefore the disease is most prevalent in North America, Europe, and Australasia. However, CF can affect nearly every race and ethnicity, including African, Latin American, and Middle Eastern populations.

The prevalence of CF and the spectrum of CFTR mutations vary considerably among populations and regions of the world. Birth prevalence is reported as a number of live births per case of CF. Common/important mutations in each region are listed below the prevalence. The birth prevalence can vary greatly between ethnic groups in a country.

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 outcomes.

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 second-hand 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.

Causes of Cystic Fibrosis 

Cystic fibrosis is due to a mutation in the CF gene on chromosome 7. The CF gene encodes a protein known as the cystic fibrosis transmembrane regulator (CFTR). The abnormal CFTR protein in patients with CF leads to disruption of chloride channels on the cells. This causes the abnormal production of mucus which leads to lung infection that can damage the lungs.

 

Disruption of chloride channels on a cell wall

Cystic Fibrosis symptoms

1. Salty tasting skin
2. Persistent coughing
3. Shortness of breath
4. Wheezing
5. Poor weight gain in spite of excessive appetite
6. Greasy, bulky stools
7. Nasal polyps: small fleshy growths found in the nose.

Diagnosis and tests

• CF is usually diagnosed by carrying out a sweat test. Sweat is collected and the amount of chloride, a component of salt in the sweat, is measured. If a high level of chloride is present then the patient has cystic fibrosis.
• Genetic tests can also be carried out by analyzing cells from inside the cheek or a blood sample. These tests are mainly used to find out if a person carries the CF gene, but they can also be used to confirm a CF diagnosis if a sweat test result is unclear.

Treatment and medications

• There is currently no cure for CF. There is, however, forms of treatment that can be used in order to tackle the symptoms of the disease and improve the quality of life. CF symptoms can vary from person to person, and so treatment plans for people with CF will be individualized.
• Inhaled medication is commonly used as it is effective at reaching the airways. The medication can be given by aerosol or as a metered-dose inhaler. These medications can thin mucus, kill bacteria and draw more water into the airways.
• Antibiotics are an important part of regular care for people with CF; these can be taken orally, intravenously or inhaled.
• Other drugs, such as ibuprofen and azithromycin, have been found to preserve and improve lung function, and are now considered to be a part of standard therapy for people with CF.

Cystic Fibrosis Diet

If you have CF, you need to eat a balanced diet consisting of fat, protein, dairy, fruits, and vegetables. You’ll need to increase the amount of each in your diet to ensure that your body is able to absorb enough of these nutrients.

You can do this by adding the following to your diet:

• Protein: Foods high in protein, such as beef, chicken, eggs, fish, and soy, are important for preventing muscle loss.
• Zinc: Foods high in zinc include kidney beans, beef, spinach, liver, eggs, and seafood. Zinc is important for staving off infections.
• Salt: People with CF have saltier sweat, which may cause electrolyte imbalance and dehydration. Salty snacks, pickles, and sports drinks can help replace the salt you lose while sweating. You can also cook vegetables in chicken broth instead of water.
• Calcium: Foods high in calcium help reduce your risk of osteoporosis, a concern for people with CF. Dairy products, such as high-fat yogurt, whole milk, and high-fat cheese are all good sources.
• Iron: Iron helps fight off infection and produces oxygen-carrying red blood cells. Foods high in iron include liver, tuna, lamb, seafood, eggs, beef, and turkey.
• Antioxidants: Fruits and vegetables are good sources of antioxidants and important for fighting off bacterial infection. People with CF may experience high amounts of airway inflammation in the lungs, making the bacterial infection more likely and very dangerous to your health.
• Fiber: Your doctor may recommend eating high-fiber foods to help reduce the risk of intestinal blockages. Many high-fiber breakfast cereals are also high in protein.

Prevention

1. Wash hands frequently
2. Get a flu shot every year
3. Do not smoke and avoid second-hand smoke
4. Avoid unnecessary contact with people who have colds or other contagious illnesses