Can a cold or bronchitis turn into pneumonia? How can you tell?

Yes, a cold or bronchitis can turn into pneumonia.

Bronchitis occurs when a cold spreads to the airways that carry air into your lungs (bronchial tubes). A chest cold is often called acute bronchitis, which is an inflammation and swelling of the bronchial tubes. Acute bronchitis is often caused by a viral infection and tends to last less than 3 weeks. By contrast, chronic bronchitis is a cough that lasts for 2 to 3 months a year for years.

If the infection spreads from the airways to the air sacs in your lungs, bronchitis can then turn into pneumonia, an infection in the lungs' air sacs (alveoli). With pneumonia, the air sacs can fill with fluid, resulting in cough, fever, chills and breathing difficulty.

Symptoms that suggest a cold has morphed into bronchitis may include:

• Runny nose
• Low-grade fever
• Chest congestion
• Wheezing
• Yellow or green mucus
• Feeling run-down

Bronchitis usually resolves on its own with rest and the use of cough suppressant and/or pain killers.

Signs that bronchitis is turning into pneumonia may include:

• Cough
• Green, yellow or bloody mucus
• Fever
• Chills
• Shortness of breath
• Rapid breathing
• Chest pain
• Loss of appetite
• Low energy
• Fatigue
• Nausea and vomiting in children
• Confusion in older people

Blood tests and imaging exams may be needed to diagnose pneumonia, along with other tests that can identify the bug that is causing pneumonia, which can help guide treatment. Antibiotics may be needed if the infection is bacterial.