DEAR DOCTORS: My wife and I both had Covid-19. I recovered, but my wife kept feeling sick. We worried it might be long Covid. But when she saw her doctor, she got diagnosed with walking pneumonia. She took antibiotics and got better. How is walking pneumonia different from regular pneumonia?
DEAR READER: Walking pneumonia is a term that is often used to describe a mild case of pneumonia. The medical term is atypical pneumonia.
The potential causes and physical symptoms of atypical pneumonia and "regular" pneumonia are basically the same. The difference between the two lies in the degree of illness. Someone with walking pneumonia can have symptoms that are so mild, they may not even realise that they are ill. Instead, they may think that they have somehow overexerted themselves, which has led to their feeling tired and run-down.
To understand pneumonia, let's start with the lungs. They are made up of a series of branching tubes that gradually go from large to small, like the trunk and branches of a tree. The smallest of these branches are known as bronchioles. Instead of leaves, though, bronchioles end in clusters of tiny and delicate air sacs known as alveoli. To give you an idea of how small these are, the average healthy adult has an estimated 480 million alveoli.
The alveoli, which are lined with capillaries, are where the oxygen that we breathe in passes to the blood and travels to sustain the tissues throughout the body. This is also where carbon dioxide, which our cells produce as a byproduct of metabolism, leaves the blood and exits via each exhaled breath.
When someone has pneumonia, it means that one or both lungs have become infected. While the most common cause is bacteria, viruses and fungi can cause pneumonia as well. It's not uncommon for someone whose immune system has been sapped by a viral infection to develop pneumonia as a secondary bacterial infection. The infection causes the alveoli to become inflamed, which results in the production of fluids or pus. These interfere with the gas exchange that supplies the body with oxygen and carries away carbon dioxide.
In regular pneumonia, symptoms typically include fever, chills, pain or pressure when coughing, a wheezing sound when breathing in, shortness of breath, and fatigue or exhaustion. In so-called walking pneumonia, the major physical symptoms are either milder or, in some cases, not present at all. They can be confused for a cold or the flu.
Some people report only feeling tired and run-down. This is because the buildup of fluid in the alveoli prevents adequate oxygen to get to the tissues of the body. Diagnosis may include X-rays to look for fluid buildup in the lungs and lab tests to identify the pathogen. When bacterial, as in your wife's case, antibiotics are used.
Despite being a milder illness, walking pneumonia is serious. It's crucial to see a doctor and follow their treatment plan. Most people begin to feel better several days into their course of antibiotics; however, it's important to be patient and take it easy. Full recovery can take up to a month or more. Universal Features Syndicate
Dr Eve Glazier is an internist and associate professor of medicine at UCLA Health. Dr Elizabeth Ko is an internist and assistant professor of medicine at UCLA Health.
