The sticky mucus associated with cystic fibrosis causes many complications, the most common in the respiratory, digestive and reproductive systems.

Respiratory system complications

  • Bronchiectasis. Cystic fibrosis is one of the leading causes of bronchiectasis, a condition which damages the airways, making it harder to move air in and out of the lungs.
  • Chronic infections. Thick mucus in the lungs and sinuses provides an ideal breeding ground for bacteria and fungi. People with cystic fibrosis may have frequent bouts of sinusitis, bronchitis or pneumonia.
  • Nasal polyps. Because the lining inside the nose is inflamed and swollen, it can develop soft, fleshy growths (polyps). Nasal polyps can obstruct your breathing during sleep.
  • Cough up blood. Over time, cystic fibrosis can cause thinning of the airway walls. As a result, teenagers and adults with cystic fibrosis may cough up blood (hemoptysis).
  • Pneumothorax. This condition, in which air collects in the space that separates the lungs from the chest wall, is also more common in older people with cystic fibrosis. Pneumothorax can cause chest pain and breathlessness.
  • Collapsed lung. Repeated lung infections damage the lungs, making it more likely for the lung to collapse.
  • Respiratory failure. Over time, cystic fibrosis can damage lung tissue so badly that it no longer works. Lung function typically worsens gradually, and it eventually can become life-threatening.

Digestive system complications

  • Nutritional deficiencies. Thick mucus can block the tubes that carry digestive enzymes from your pancreas to your intestines. Without these enzymes, your body can't absorb protein, fats or fat-soluble vitamins.
  • Diabetes. The pancreas produces insulin, which your body needs to use sugar. Cystic fibrosis increases the risk of diabetes. Nearly 20 percent of people with cystic fibrosis develop diabetes by age 30.
  • Blocked bile duct. The tube that carries bile from your liver and gallbladder to your small intestine may become blocked and inflamed, leading to liver problems and sometimes gallstones.
  • Rectal prolapse. Frequent coughing or straining during constipation can cause internal rectal tissue to protrude outside the anus.
  • Intussusception. Children with cystic fibrosis are at higher risk of intussusception, a condition in which a section of the intestines folds in on itself like an accordion. The result is bowel obstruction, an emergency that requires immediate treatment.

Reproductive system complications

Almost all men with cystic fibrosis are infertile because the tube that connects the testes and prostate gland (vas deferens) is either blocked with mucus or missing entirely. Certain fertility treatments and surgical procedures sometimes make it possible for men with cystic fibrosis to become fathers.

Although women with cystic fibrosis may be less fertile than other women, it's possible for them to conceive and to have successful pregnancies. Still, pregnancy can worsen the signs and symptoms of cystic fibrosis, so be sure to discuss the possible risks with your doctor.

Other complications

  • Osteoporosis. People with cystic fibrosis are at higher risk of developing osteoporosis, a dangerous thinning of bones.
  • Electrolyte imbalances. Because people with cystic fibrosis have saltier sweat, the balance of minerals in their blood may be upset. Signs and symptoms include increased heart rate, fatigue, weakness and low blood pressure.
Jun. 13, 2012

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