How Bronchiectasis Is Diagnosed

Understanding How Bronchiectasis is Diagnosed

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Bronchiectasis is among a group of lung disorders classified as obstructive lung diseases. A diagnosis of bronchiectasis is sometimes difficult to make, as bronchiectasis symptoms are often mistaken for other lung disorders, such as emphysema, pneumonia, or lung cancer.

Specific tests, such as pulmonary function tests, chest X-rays, and sputum cultures can all help narrow down a diagnosis of bronchiectasis.


Because the symptoms of bronchiectasis are so similar to numerous other lung conditions, such as bronchitis or asthma, this condition cannot be diagnosed based on self-checks.

That said, it's important to pay attention to the signs and symptoms, and to describe them to your healthcare provider as soon as possible to prevent further damage.

Seek professional care promptly if you notice:

  • A chronic cough with thick mucus that's difficult to clear
  • Wheezing
  • Fatigue
  • Weakness
  • Clubbing of the fingers (in which the tips of the fingers enlarge and the nail slopes downward)

Labs and Tests

The first thing that your healthcare provider is likely to do is take a thorough history and perform a physical examination. This includes asking questions about your health history and exposures to airway irritants, such as cigarette smoke, air pollution and chemicals in the workplace.

A head-to-toe physical assessment will include listening to your lungs with a stethoscope and examining your chest wall for abnormalities. After these exams, if your practitioner still suspects a diagnosis of bronchiectasis, the following tests may be ordered to confirm it.

Pulmonary Function Test

Pulmonary function tests help your medical team assess your lung function by measuring how efficiently air flows. This can determine the amount of lung damage present.

There are several types of pulmonary function tests that can be helpful in making a diagnosis of bronchiectasis and other types of COPD, including:

  • Spirometry, a noninvasive test that measures lung function as you breathe through a tube
  • Lung diffusion studies, another noninvasive test that determines how much carbon monoxide you inhale versus exhale to help assess how efficiently your lungs are performing
  • Lung plethysmography, a test that looks at your total lung capacity, or the amount of air you're able to take in as breath and how much is left over after you exhale (known as functional residual volume)

Sputum Culture

People with bronchiectasis are prone to frequent lung infections. A sputum culture is a lab test that analyzes a small amount of sputum (mucus) in an agar dish (growing medium) to look for bacterial growth. The test helps identify the specific bacteria strain(s) in the mucus, which can lead to more efficient treatment with the type of antibiotic that is most likely to target the bacteria.


Imaging tests are also common methods used in the diagnosis of bronchiectasis.

Chest X-Ray

This noninvasive imaging technique uses electromagnetic waves to create a picture of your lungs and diaphragm. X-rays are performed in some healthcare providers' offices, medical imaging centers, and hospitals.

Generally speaking, abnormalities in the lungs due to lung diseases do not show up until the damage is severe. So, while a chest X-ray does not provide a definitive diagnosis of bronchiectasis or other forms of lung disease, it does help support one.

Chest CT Scan

A chest CT is often used as part of the diagnosis of bronchiectasis, and your healthcare provider may also order a chest CT if you've had a change in symptoms, an infection is not resolving, or you are getting ready for surgery.

A chest CT provides a more detailed image than an X-ray, as it takes numerous cross-sectional pictures (slices) of your lungs and chest and combines them to form a 3D image.

The test is usually performed in a medical imaging center or a hospital. Physicians may also order a high-resolution CT of the chest to aid in this diagnosis.

Differential Diagnoses

Before reaching a diagnosis of bronchiectasis, your practitioner may also test you for associated conditions, such as cystic fibrosis or tuberculosis. This will help rule out or confirm a diagnosis of bronchiectasis.

Other conditions your healthcare provider will look into include:

  • Infection: Pneumonia or bronchitis could result in similar symptoms to bronchiectasis.
  • Cystic fibrosis: This genetic condition affects the lungs and other organs and may result in increased mucus secretions.
  • Tuberculosis: Bronchiectasis may occur in conjunction with or be caused by tuberculosis, a disease caused by bacteria that usually attacks the lungs. Your healthcare provider will perform specific lab work to rule out this disease.
  • Immune conditions: Autoimmune conditions such as asthma or an immune deficiency such as alpha1-antitrypsin (AAT) deficiency can produce symptoms similar to those of bronchiectasis.

A Word From Verywell

While bronchiectasis can take time to diagnose, there are several diagnostic tests that can help clarify the situation. Several therapies have been shown to be beneficial, and lifestyle modifications can also help. The most important thing is to seek treatment quickly to prevent further damage to the lungs and to identify your best treatment plan.

Frequently Asked Questions

  • Can bronchiectasis be diagnosed with an X-ray?

    Unless the condition is very advanced, no. A radiology technician or pulmonologist (healthcare provider who specializes in respiratory diseases) may be able to see suspicious changes in the airways on an X-ray. However, a CT scan is necessary to definitively diagnose bronchiectasis.

  • Is bronchiectasis a terminal condition?

    No. Most people with bronchiectasis not associated with cystic fibrosis have a normal life expectancy, although little research has been done regarding the prognosis of the condition. What is known is that the sooner bronchiectasis is diagnosed and treated, the better the outcome.

  • What can trigger an exacerbation of bronchiectasis?

    The most common cause of a flare-up of bronchiectasis is a respiratory infection. Symptoms of an exacerbation are a worsened cough, increases in the amount of mucus that comes up with the cough, and dyspnea (trouble breathing).

11 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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Additional Reading

By Deborah Leader, RN
 Deborah Leader RN, PHN, is a registered nurse and medical writer who focuses on COPD.