What is cystic fibrosis?
Cystic fibrosis is an inherited disease affecting the glands that produce mucus, tears, sweat, saliva and digestive juices in the body. Normally, these secretions are thin and slippery, but in CF, a defective gene causes the secretions to become thick and sticky leading to obstruction of the lungs and preventing the pancreas from secreting the enzymes necessary for the digestion of fats. Respiratory failure is the most dangerous consequence of CF.
What is the cause?
Cystic fibrosis is a genetic disease. The genes cause abnormal mucus in the respiratory and gastrointestinal tracts and sweat glands. This causes lung obstruction and infection, poor digestion and food absorption. The greatest risk factor for CF is a family history of the disease. If both parents come from families with CF, the chances are one in four that each of their children will also have CF. Cystic fibrosis occurs mainly in whites of Northern European ancestry. It is relatively rare in black Americans and Asian Americans. Hence, if one has a family history of cystic fibrosis, it is advisable to seek genetic counselling before starting a family. People who carry the CF gene are healthy and have no symptoms of the disease. The environment, diet, exercise, or other lifestyle behaviours do not cause CF. It is not contagious and cannot be passed from one person to another except through inheritance.
What are the symptoms?
The specific signs and symptoms of CF vary depending on the severity of the disease. In some newborns the first sign may be a blockage of the intestines due to thick, sticky stools (meconium)Later symptoms:
- poor weight gain despite good appetite
- bad-smelling, large, fatty stools
- a barrel-chested appearance
- chronic cough
- frequent and severe respiratory infections with sticky sputum
- salty sweat
- enlarged liver and spleen
- blockage in the bowel
- delayed growth
- frequent chest and sinus infections with recurring pneumonia or bronchitis
- enlargement or rounding (clubbing) of the fingertips and toes
- cirrhosis of the liver due to inflammation or obstruction of the bile ducts
How is the diagnosis made?
The standard diagnostic test for CF is a sweat test, which measures the amount of sodium and chloride in a person's sweat. A consistently high level of salt indicates CF. In some cases a genetic analysis of a blood sample is performed to confirm the diagnosis of CF. Tests may also help determine the extent and severity of CF.
What are the complications?
- Chronic bronchitis
- Fluid and electrolyte imbalance
- Nasal polyps
- Rectal prolapse
What is the treatment?
Cystic fibrosis is currently considered incurable and is often fatal in childhood. However, careful long-term care by parents and professionals can help the patients lead reasonably comfortable lives. Children with milder forms can live till adulthood, especially if the disorder is detected early.
Researchers have identified the gene that causes cystic fibrosis. New strategies are aimed at developments to prevent and treat this disease. Management of the disease varies widely from person to person and generally focuses on respiratory and digestive problems. It usually involves a combination of medications and home treatments (including respiratory and nutritional therapies), as well as hospital care for some complications. Newer treatments are allowing some of those with CF to live well into their 40s, 50s, and later years. However, there is no cure for the disease.MEDICATIONS
- Mucus-thinning drugs: these drugs help in making mucus thinner and easier to cough up
- Bronchodilators: use of medications such as albuterol may help keep the airways in the lungs open by helping to clear thick bronchial secretions
- Bronchial airway drainage: people with CF need a way to physically remove thick mucus from their lungs. This is often done by manually clapping on the front and back of the chest. In some cases an electric chest clapper, known as a mechanical precursor, is used. Some people may use an inflatable vest with a machine attached that vibrates at high frequency to help cough up secretions
- Oral enzymes and better nutrition: CF can make the patients malnourished because the pancreatic enzymes needed for digestion do not reach the small intestine. As a result, the patient may need 50 percent to 100 percent more calories than normally required.
- Supplemental high-calorie nutrition, special vitamins and enteric-coated oral pancreatic enzymes can enable the patients to maintain and even gain weight
- Antibiotics may also be required in case of lung infections
- The patient should eat a low-fat diet with adequate proteins
- Vitamin and mineral supplements may be necessary
- Intake of liquids should be encouraged, which help in thinning mucus
- Consultation with a dietician is advisable for specific instructions
Many treatments exist for the symptoms and complications of CF. The main goal is to treat infections, keep the lungs free of sputum, improve airflow and maintain adequate calories and nutrition.