Bronchiectasis

Bronchiectasis is a condition where the bronchial tubes of your lungs are permanently damaged, widened, and thickened. These damaged air passages allow bacteria and mucus to build up and pool in your lungs. This results in frequent infections and blockages of the airways.

There is no cure for bronchiectasis, but it is manageable. With treatment, you can typically live a normal life. However, flare-ups must be treated quickly to maintain oxygen flow to the rest of your body and prevent further lung damage.

Any lung injury can cause bronchiectasis. There are two main categories of this condition. One is related to having cystic fibrosis (CF), and is known as CF bronchiectasis. CF is a genetic condition that causes an abnormal production of mucus.

Symptoms of bronchiectasis can take months or even years to develop. Some typical symptoms include:

  • chronic daily cough
  • abnormal sounds or wheezing in the chest with breathing
  • shortness of breath
  • chest pain
  • coughing up large amounts of thick mucus every day
  • fatigue
  • change in the structure of fingernails and toenails, known as clubbing
  • frequent respiratory infections

The exact cause of bronchiectasis is unknown in about 50 percent Trusted Source of the cases of non-CF bronchiectasis.

For others, it’s related to genetic abnormalities that affect the lungs and other medical conditions. Avoiding smoking, polluted air, cooking fumes, and chemicals can help protect your lungs and maintain lung health.

You and your children should be vaccinated against the flu, pertussis, and measles, as these conditions have been linked to the condition in adulthood.

But often when the cause is unknown, prevention is difficult. Early recognition of bronchiectasis is important so that intervention can begin before significant lung damage occurs.

Surfactant

Surfactant dysfunction is a lung disorder that causes breathing problems. This condition results from abnormalities in the composition or function of surfactant, a mixture of certain fats (called phospholipids) and proteins that lines the lung tissue and makes breathing easy. Without normal surfactant, the tissue surrounding the air sacs in the lungs (the alveoli) sticks together (because of a force called surface tension) after exhalation, causing the alveoli to collapse. As a result, filling the lungs with air on each breath becomes very difficult, and the delivery of oxygen to the body is impaired.

The signs and symptoms of surfactant dysfunction can vary in severity. The most severe form of this condition causes respiratory distress syndrome in newborns. Affected babies have extreme difficulty breathing and are unable to get enough oxygen. The lack of oxygen can damage the baby’s brain and other organs. This syndrome leads to respiratory failure, and most babies with this form of the condition do not survive more than a few months.

Less severe forms of surfactant dysfunction cause gradual onset of breathing problems in children or adults. Signs and symptoms of these milder forms are abnormally rapid breathing (tachypnea); low concentrations of oxygen in the blood (hypoxemia); and an inability to grow or gain weight at the expected rate (failure to thrive).

There are several types of surfactant dysfunction, which are identified by the genetic cause of the condition. One type, called SP-B deficiency, causes respiratory distress syndrome in newborns. Other types, known as SP-C dysfunction and ABCA3 deficiency, have signs and symptoms that range from mild to severe.

Surfactant dysfunction is caused by mutations in one of several genes, including SFTPBSFTPC, and ABCA3. Each of these genes is involved in the production of surfactant. The production and release of surfactant is a complex process. 

Surfactant dysfunction can have different inheritance patterns depending on its genetic cause.

When caused by mutations in the SFTPB or ABCA3 gene, this condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition.

When caused by mutations in the SFTPC gene, this condition has an autosomal dominant inheritance pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In about half of cases caused by changes in the SFTPC gene, an affected person inherits the mutation from one affected parent. The remainder result from new mutations in the gene and occur in people with no history of the disorder in their family.

Cystic Fibrosis

Cystic fibrosis is an inherited disease characterized by the buildup of thick, sticky mucus that can damage many of the body’s organs. The disorder’s most common signs and symptoms include progressive damage to the respiratory system and chronic digestive system problems. The features of the disorder and their severity varies among affected individuals.

Cystic fibrosis is a common genetic disease within the white population in the United States. The disease occurs in 1 in 2,500 to 3,500 white newborns. Cystic fibrosis is less common in other ethnic groups, affecting about 1 in 17,000 African Americans and 1 in 31,000 Asian Americans.

Mutations in the CFTR gene cause cystic fibrosis. The CFTR gene provides instructions for making a channel that transports negatively charged particles called chloride ions into and out of cells. Chloride is a component of sodium chloride, a common salt found in sweat. Chloride also has important functions in cells.

Mutations in the CFTR gene disrupt the function of the chloride channels, preventing them from regulating the flow of chloride ions and water across cell membranes. As a result, cells that line the passageways of the lungs, pancreas, and other organs produce mucus that is unusually thick and sticky. This mucus clogs the airways and various ducts, causing the characteristic signs and symptoms of cystic fibrosis.

This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition.