How Chronic Bronchitis Is Diagnosed

Coughing is how your body clears the lungs of dust and other irritants. Sometimes, though, a cough can mean something more. If you have a frequent cough that produces mucus, a slippery liquid, and it has been going on for weeks or even years, you should call your doctor.

A frequent productive cough is a primary symptom of chronic bronchitis, a condition where the tubes that bring air to your lungs become inflamed. This condition falls under the umbrella of chronic obstructive pulmonary disease (COPD). Other conditions can cause frequent coughing as well.

Your doctor will perform a physical exam and a series of tests, including lung function tests, imaging, and blood tests to determine whether you have chronic bronchitis.

Self-Checks/At-Home Testing

You may not have any symptoms or very mild symptoms at first. As the disease progresses, though, you will start to have more severe symptoms.

Common symptoms of chronic bronchitis include:

• A frequent cough that produces mucus (a cough with mucus has to last most days for at least three months to a year for 2 years in a row to be classified as chronic bronchitis)
• Shortness of breath
• Wheezing
• A whistling or squeaky sound when you breathe
• Tightness in your chest

It's difficult to tell on your own whether you have chronic bronchitis or a cold because the symptoms can be similar. If you're trying to figure out whether you have a cold or something more serious, you can ask yourself some simple questions:

• Does COPD or chronic bronchitis run in my family?
• Do I smoke or have I ever been a smoker?
• Do I live with someone who smokes or have regular exposure to secondhand smoke?
• Do I work in a place where I'm often exposed to dangerous fumes or dust?
• Do I get short of breath more quickly than people around me?
• Is my cough becoming more persistent or has it lasted for several months?
• Have I missed work because of my cough or had to reduce my daily activities?
• Have I been hospitalized for breathing problems or my cough?

Checking Your Lung Function At Home

There are also exercises you can do at home to check your lung function. If you have a pulse oximeter, this can help you track your oxygen saturation, the amount of oxygen in your blood.

A peak flow meter can also help you check your lung function. This hand-held device measures how well your lungs are moving air.

The steps to use a peak flow meter are as follows:

• Set the peak flow meter to zero.
• Attach the mouthpiece to the peak flow meter.
• Stand up so that you can take a deep breath. Stay standing and do not move throughout the test.
• Take a deep breath in and place the mouthpiece around your lips, sealing it tightly.
• Breathe out as hard as you can for no longer than one second.
• Write down the reading on the gauge.
• Place the peak flow meter back to zero before blowing into the mouthpiece again.
• Repeat the blowing and recording process two more times.

Physical Examination

Your doctor will first ask about your family and personal health history. They will want to know about:

• Diseases or conditions that run in your family
• Your diet
• Your exercise routine
• Past surgeries
• Past diagnoses or other medical problems you have
• Any medications or supplements you take
• Where you live and work
• Whether you smoke, vape, or use any drugs or alcohol

Next, they will perform a full physical assessment. This includes an exam from head to toe, along with measurements of your blood pressure, temperature, heart rate, and oxygen saturation.

One of the most important checks your doctor will perform during the physical assessment is listening to your lungs. Lung sounds can tell a lot about your health. Normally, your doctor should be able to hear loud, clear movement of air in your lungs with a stethoscope. Other sounds are generally a cause for concern.

If your doctor uncovers anything that hints at a bigger problem than a cold or simple cough, your doctor will perform additional tests to find the root cause and severity of the problem.

Labs and Tests

Lung Function Tests

Lung function tests are performed by your doctor, nurse, or even a respiratory therapist, and are used to measure your lung volume, how much your lungs are able to expand with each breath, and how strong your breaths are.

These tests include:

• Cardiopulmonary stress testing, which can help pinpoint the source of your shortness of breath and to determine their exercise limitation
• Spirometry, which checks how much air you can breathe in and out of your lungs and how easily and fast you can the blow the air out of your lungs
• Lung volume tests, which measures the volume of air in the lungs, including the air that remains at the end of a normal breath
• Lung diffusion capacity, which shows how well oxygen and carbon dioxide are transferred between your lungs and blood
• Pulse oximetry, which measures the level of oxygen in your blood
• Fractional exhaled nitric oxide tests, which measures the amount of nitric oxide that is exhaled from a breath (high levels of nitric oxide are associated with swelling of the airways)

You may also have an electrocardiogram done to check the impact of your breathing on your heart function.

Imaging Studies

Imaging can help your doctor visualize your lungs. Chest X-rays and computed tomography scans can help your doctor properly diagnose chronic bronchitis.

Blood Tests

An arterial blood gas is a test that allows your doctor to measure your oxygen levels and other gas levels. Each of these values like oxygen, carbon dioxide, and bicarbonate can help your doctor tell how effectively you are breathing.

Differential Diagnoses

A number of conditions can cause a chronic cough, including:

• Asthma
• Gastroesophageal reflux disease (GERD)
• Bronchiectasis
• Nonasthmatic eosinophilic bronchitis
• Tuberculosis

Using certain medications like angiotensin-converting-enzyme (ACE) inhibitors, which are used to treat high blood pressure and heart failure, can also result in a chronic cough.

More serious causes of a chronic cough can include:

• Bronchogenic carcinoma
• Carcinomatosis
• Sarcoidosis
• Tuberculosis
• Left ventricular heart failure
• Upper airway dysfunction
• Interstitial lung disease
• Psychogenic cough
• Cystic fibrosis

Summary

If your doctor suspects that you have chronic bronchitis, they will first perform a physical exam and take your history. Then they will perform some tests, including lung function tests, X-rays and CT scans, and blood tests to see how well your lungs are functioning and rule out other potential causes of your symptoms.

A Word From Verywell

There are a lot of things that could cause a chronic cough. Chronic bronchitis is just one of them, but it may be the likely cause if you are a smoker. If your cough produces mucus, there is a good chance that you have chronic bronchitis.

To find out what is causing your cough, your doctor will learn more about your medical history and perform a series of tests. If you have a cough that has lasted on and off for about two years, you should see your doctor for a full examination.