What is bronchitis?

Bronchitis happens when the tubes (airways) in your lungs, called bronchial tubes, get swollen and make you cough, often with mucus.1 This usually occurs because of a virus or breathing in things that irritate your lungs, like cigarette smoke, fumes, dust, and air pollution.2
In Bronchitis caused by infection, the infection usually starts in your nose or throat and then moves to your bronchial tubes. As your body fights the disease, your bronchial tubes swell up. This swelling makes you cough. Sometimes, you have a dry cough, but often, you cough up mucus. The swelling also makes your airways narrower, which can cause wheezing (a high-pitched whistle sound you may hear when your airway is blocked), chest tightness, and shortness of breath. Over time, your immune system will eliminate the infection, and your airways will return to normal.2

Types of bronchitis

Bronchitis can be either acute (short-term) or chronic (long-term).1 When people talk about bronchitis, they are usually referring to acute bronchitis.1

Acute bronchitis

is common and usually happens because of a viral infection. It can spread from person to person. Most people get better within a few days or weeks.1

Persistent cough, with or without sputum production

A persistent hacking cough that lasts for at least 5 days.

Prolonged or forceful coughing may lead to chest pain usually self- limiting.

Fatigue and general bodily discomfort.5

Chronic bronchitis

Lasts for at least three months and tends to come back at least two years in a row. With chronic bronchitis, breathing can be difficult because the lining of the airways stays swollen and produces more mucus.1

Cough with a lot of mucus.

Along with coughing and wheezing, you might feel some mild discomfort in your chest.6

Chronic bronchitis can be a sign of a larger lung problem called chronic obstructive pulmonary disease (COPD). 3

Causes of bronchitis

Acute Bronchitis


Viral InfectionsMost often caused by the same viruses that lead to colds or the flu.

Bacterial Infections
Occasionally, bacteria can also trigger acute Bronchitis.


In both viral and bacterial cases, the body's defense mechanism kicks in. The bronchial tubes then swell and produce more mucus as the body fights the infection. This swelling and mucus production narrows the airways, making breathing harder.

Chronic Bronchitis


Air Pollution
Long-term exposure to air pollution and other irritants, such as chemical fumes or dust.

Smoking
Prolonged smoking, inhaling second-hand cigarettes, marijuana, or Long-term use of e-cigarettes.7

Biomass
Breathing in smoke from burning solid fuels like wood or charcoal at home could increase your risk for chronic bronchitis.15

Complications of bronchitis

Pneumonia
If your bronchitis symptoms, like coughing and fatigue, persist for several weeks and you start feeling short of breath, feverish, or experiencing chest or shoulder pain, your doctor might suspect pneumonia.
Bronchitis can progress to pneumonia in anyone, but people with underlying health issues or weakened immune systems are at higher risk of serious complications.

Asthma Flares
If you have asthma or another chronic lung condition, acute bronchitis could trigger a flare-up. People with asthma or COPD already have some level of inflammation in their bronchial tubes.
Bronchitis adds to this inflammation, increasing the likelihood of an asthma attack.

Bronchitis diagnosis and tests

Acute Bronchitis:

In the early stages of illness, it's hard to tell if you have bronchitis or a regular cold. When you see your doctor, they'll listen to your lungs with a stethoscope.
Acute bronchitis is usually diagnosed based on symptoms and a physical exam. This includes checking your medical history and examining your lungs.
Your doctor will also measure your oxygen levels and check your pulse, temperature, and how fast you're breathing. This helps assess how serious the illness is.


Chest X-rays
Chest X-rays for acute bronchitis often look normal or show slight thickening of the airway linings.

Rapid Testing for Infections
Testing for respiratory infections like influenza isn't always necessary but can be crucial during flu season or pandemics like COVID-19. It helps quickly diagnose infections to start treatment and prevent spreading.

Spirometry
This test measures lung function in bronchitis patients. It often shows temporary narrowing of the airways, which usually improves within a few weeks.

Lab Tests
Blood tests may be done if you have a fever. These tests can show a slight increase in white blood cells in some cases of acute bronchitis.

Advanced Testing
In some cases, tests like multiplex PCR or procalcitonin levels might be used to decide if antibiotics are necessary to treat bronchitis. This helps in making better treatment decisions.

Chronic Bronchitis:

Tests that help confirm chronic bronchitis include:

Pulmonary function test
This test evaluates how well your lungs work

Chest x-ray
Particularly important for older adults and when symptoms suggest pneumonia.

Oxygen saturation measurement
This test checks how much oxygen is in your blood, which is crucial for assessing lung function.

Complete blood count with differential
This test provides important information about the blood cells, which can indicate inflammation.

Sputum culture
If a bacterial infection is suspected, this test can identify the specific bacteria causing the infection.

Prevention of bronchitis

To steer clear of bronchitis, focus on preventing colds and flu. Follow these habits7:

Wash your hands often

Get a flu shot yearly

Cover your mouth while coughing to prevent spreading germs

Avoid irritants like dust and chemicals; wear a mask if you can't avoid them

Avoid crowded places

Wear a mask

Don't smoke or inhale second-hand smoke

Eat well and sleep enough to keep your immune system strong

Treatment of bronchitis

Acute bronchitis is often self-limiting, meaning that in most situations, it tends to improve on its own within a few weeks without needing any specific treatment. This is because the majority of bronchitis cases are caused by viruses, which antibiotics cannot treat effectively.

Your doctor probably won't give you medicine for bronchitis unless it's necessary. However, if your doctor thinks your bronchitis might be due to a bacterial infection, they may prescribe antibiotics to help.9

The doctor might prescribe medication to help with symptoms or the underlying cause:

  1. Antiviral medicines: If your bronchitis is because of the flu, antivirals might be prescribed to help you recover faster.

  2. Bronchodilators: These drugs open your airways if you have trouble breathing.

  3. Anti-inflammatory medicines: Corticosteroids and other drugs like ibuprofen, paracetamol, and naproxen are used to reduce inflammation.

  4. Cough suppressants, like syrups, can help with a persistent cough.

  5. Antibiotics: These medicines are generally not prescribed by doctors unless the cause is bacteria.

Using a humidifier or taking warm showers can also ease breathing by loosening mucus.
However, if you have chronic bronchitis, pulmonary rehabilitation and medications could help. It's a program where a breathing specialist teaches you exercises to breathe better and improve your ability to do physical activities.10,11,13,14

Bronchitis recovery

Patients with acute bronchitis typically recover well. This condition usually resolves on its own in healthy individuals, but it might cause people to miss work or school. In rare cases, bronchitis can worsen for those with heart or lung issues or other health problems.12

Reference

  1. NHLBI. Bronchitis | NHLBI, NIH [Internet]. www.nhlbi.nih.gov. 2022. Available from: Click here
  2. American Lung Association. Learn About Bronchitis | American Lung Association [Internet]. www.lung.org. Available from: Click here
  3. Cleveland Clinic. Bronchitis Symptoms & Treatment [Internet]. Cleveland Clinic. 2022. Available from: Click here
  4. Bronchitis [Internet]. NHS inform. Available from: Click here
  5. Singh A, Avula A, Zahn E. Acute bronchitis [Internet]. Nih.gov. StatPearls Publishing; 2023. Available from: Click here
  6. Widysanto A, Mathew G. Chronic Bronchitis [Internet]. National Library of Medicine. StatPearls Publishing; 2022. Available from: Click here
  7. Key AP. Bronchitis. Lung Disease & Respiratory Health. WebMD. [Internet]. 2024. [Cited 07 July 2024] Available from: Click here
  8. What Is Bronchitis? Symptoms, Causes, Diagnosis, Treatment, and Prevention [Internet]. EverydayHealth.com. Available from: Click here
  9. Clinic M. Bronchitis - Diagnosis and treatment - Mayo Clinic [Internet]. Mayoclinic.org. 2017. Available from: Click here
  10. Bronchitis Symptoms & Treatment [Internet]. Cleveland Clinic. Available from: Click here
  11. Bronchitis: Practice Essentials, Background, Pathophysiology. eMedicine [Internet]. 2021 Jul 12; Available from: Click here
  12. University of California San Francisco. Chronic Bronchitis [Internet]. ucsfhealth.org. 2020. Available from: Click here
  13. Bronchitis Treatments & Medications | SingleCare [Internet]. SingleCare. Available from: Click here
  14. Acute bronchitis [Internet]. patient.info. [cited 2024 Jul 11]. Available from: Click here