Definition

Cystic fibrosis (CF) is an inherited disease. The defect occurs in epithelial (or lining) cells. These cells normally create a mucus. The mucus is a vital tool for many organs. CF causes the cells to produce a very thick and rubbery mucus. This most commonly causes:

• Obstructions and infections of the lungs and airways
• Malabsorption in the gastrointestinal system (stomach and intestines)

Cystic Fibrosis

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Causes

CF is an autosomal recessive disorder. This means the child inherits one defective gene from each parent. Usually the parents do not have the disease but carry the gene. These parents are called carriers.

Risk Factors

Factors that increase your chance of CF include:

• Parents who are known carriers of the CF gene
• Siblings with CF
• Parents with CF

Symptoms

The abnormally thick mucus of CF blocks certain organs. This causes many of the symptoms of CF.

Symptoms include:

• In infants:
  • Difficulty passing the first stool (meconium)
  • Meconium ileus, or intestinal obstruction (sometimes requires surgery)
• Trouble gaining weight
• Poor growth pattern
• Failure to thrive
• Malnutrition
• Bulky, bad-smelling, floating stools, due to poor digestion of fats
• Coughing and wheezing
• Repeated pneumonia]]>
• Shortness of breath
• Difficulty with exercise
• Salty skin
• Abnormally shaped clubbed finger tips
• Barrel chest
• ]]>Nasal polyps]]>
• Severe, chronic ]]>sinusitis]]>
• ]]>Pancreatitis]]>
• ]]>Insulin-dependent diabetes]]>
• ]]>Gallstones]]>
• ]]>Liver cirrhosis]]>
• Mildly decreased fertility in females
• No sperm production in males

CF is a serious life-long condition. It significantly reduces longevity. It also results in illness and poor health for most. Girls tend to be affected more severely than boys. The severity of illness can vary greatly. Some persons with mild forms of CF can live to age 60 or beyond.

Diagnosis

The doctor will ask about symptoms and medical history. A physical exam will be done. CF is suspected in a child with classic symptoms, especially if a sibling has CF.

Tests may include:

• Sweat chloride testing (still the standard for making a diagnosis of CF)
• DNA testing
• Nasal potential difference measurement
• Chest]]> and/or sinus x-rays
• Tests of pancreatic function
• Lung function tests
• Newborn screening

Treatment

There is no cure for CF. Treatment is aimed at:

• Improving nutritional status
• Preventing and treating lung infections
• Keeping the airways and lungs as clear as possible

Treatment for CF includes:

• Nutrition
  • High-calorie diet planned by a registered dietician—If your child returns to his normal weight within two years of the diagnosis, this may lead to fewer coughing episodes and better lung function. *¹]]>
  • Nutritional supplements, including fat-soluble vitamins
  • Enzyme tablets with meals to improve digestion and absorption of nutrients
  • Drinking lots of fluids, especially in hot weather or when ill
• Medication and injections
  • Medications to keep the airways clear, including:
    • Theophylline (rarely used today)
    • Bronchodilators
    • Steroid inhalers
    • DNase
    • ]]>Acetylcysteine]]>
    • Nonsteroidal anti-inflammatory drugs (uncommonly used)
  • Vaccines
  • Insulin shots if the pancreas stops producing insulin
  • Inhaled and/or systemic antibiotics to treat respiratory infections
• Treatments
  • Chest percussion and postural drainage or high-frequency chest wall oscillation (may help clear mucus from airways)
  • Oxygen therapy (may be required as the disease progresses)
• Surgery
  • Surgery (may be required to treat intestinal obstruction)
  • ]]>Lung]]> and ]]>liver transplants]]> (possible)

Researchers are exploring gene therapy. This may slow the progression of CF, or even cure it.

If you or your child is diagnosed with CF, follow your doctor's instructions .

Prevention

If you have the defective genes, there is no way to prevent CF.

Adults can be tested to see if they carry the genes before having children. Prenatal testing can determine if a baby will have CF. The availability of this testing raises many important ethical questions.