Bronchiectasis

Respiratory Infections

Severe or recurrent lung infections can damage the airways and contribute to bronchiectasis. Pneumonia, tuberculosis, whooping cough, and certain other respiratory infections may be associated with bronchiectasis, particularly when they cause significant or repeated inflammation within the lungs.

Cystic Fibrosis

Cystic fibrosis (CF) is an inherited disorder that causes abnormally thick and sticky mucus to accumulate in the lungs and other organs. In the airways, impaired mucus clearance can lead to chronic infection and inflammation and eventually contribute to bronchiectasis.

Autoimmune and Inflammatory Conditions

Some systemic inflammatory and autoimmune diseases can affect the lungs as well as other parts of the body. Rheumatoid arthritis and systemic lupus erythematosus are among the conditions that may be associated with bronchiectasis in some patients.

Immune System Disorders

Conditions that impair the immune system can make a person more susceptible to recurrent respiratory infections. Repeated or persistent infections may damage the bronchial walls over time and contribute to the development of bronchiectasis.

Allergic Bronchopulmonary Aspergillosis (ABPA)

Allergic bronchopulmonary aspergillosis is an inflammatory reaction to the fungus Aspergillus that most commonly occurs in susceptible people with asthma or cystic fibrosis. Persistent inflammation and mucus plugging associated with ABPA can damage the airways and lead to bronchiectasis.

Airway Obstruction and Other Causes

Bronchiectasis can sometimes develop when part of an airway becomes obstructed, preventing normal mucus clearance. An inhaled foreign object, an airway growth, or another localized obstruction may contribute to bronchiectasis in a specific area of the lung.

In some patients, despite a thorough evaluation, a specific underlying cause cannot be identified. This is sometimes referred to as idiopathic bronchiectasis.

Medical History and Physical Examination

The evaluation may include questions about chronic cough, mucus production, recurrent respiratory infections, shortness of breath, fatigue, previous pneumonia or tuberculosis, and other medical conditions that could contribute to airway damage. Physicians may also ask about childhood respiratory illnesses, family history, immune disorders, and the frequency and severity of pulmonary infections.

High-Resolution CT (HRCT) Scan

High-resolution computed tomography provides detailed cross-sectional images of the lungs and is the principal imaging study used to confirm bronchiectasis. HRCT can show abnormal widening of the bronchial tubes, thickening of the airway walls, mucus plugging, and the distribution and extent of disease within the lungs.

Chest X-Ray

A chest X-ray may show abnormalities that suggest bronchiectasis or another pulmonary condition, particularly when disease is more extensive. However, an X-ray may not detect mild or early bronchiectasis, so HRCT is generally needed when the condition is suspected.

Sputum Testing

A sample of mucus coughed from the lungs can be analyzed to identify bacteria, fungi, or other microorganisms that may be contributing to infection. Sputum testing can also help physicians select appropriate antimicrobial treatment when an active infection or exacerbation is present.

Pulmonary Function Tests

Pulmonary function tests (PFTs) measure airflow, lung volumes, and other aspects of respiratory function. These tests can help determine how bronchiectasis is affecting breathing, establish a baseline for future comparison, and identify accompanying airflow obstruction.

Bronchoscopy

Bronchoscopy allows a pulmonologist to examine the airways using a thin, flexible tube equipped with a camera. It is not necessary to diagnose bronchiectasis in every patient but may be useful when physicians suspect an airway obstruction, need respiratory samples that cannot be obtained otherwise, or are investigating disease concentrated in a particular area of the lung.

Testing for an Underlying Cause

Because bronchiectasis can result from many different conditions, additional testing may be recommended to identify an underlying cause. Depending on the patient’s history and clinical findings, this may include blood tests to evaluate immune function, testing for allergic bronchopulmonary aspergillosis, evaluation for cystic fibrosis or other inherited disorders, and testing for specific infections.