Conditions That Cause Chest Crackling

Are your lungs talking? Crackling in the lungs indicates that something is interfering with airflow — usually fluid or another type of buildup.

This may be a consequence of lung disease, pneumonia or another respiratory disorder, according to the National Center for Biotechnology Information. There can be other causes, too. Crackles can develop with heart ailments that cause blood flow to back up between your lungs and heart.

Robert Y. Goldberg, MD, a pulmonologist with Mission Hospital in Mission Viejo, California, explains that certain positions, such as lying down, can change the intensity of crackles in the chest and worsen shortness of breath. This may help your doctor diagnose the cause of your abnormal breathing sounds. In addition to a physical exam, your doctor may order a chest X-ray or chest CT to confirm a diagnosis, he adds.

Lung infections such as bronchitis or pneumonia can cause airway irritation and inflammation, which increases mucus production that can lead to crackling in the lungs.

Acute bronchitis is most often due to a viral infection, causing a wet cough that can last for up to three weeks, reports the National Institutes of Health (NIH).

Pneumonia can either be caused by a viral or bacterial infection of the lungs and lasts anywhere from one to four weeks, says NIH. Bacterial infections are often treated with antibiotics. Viral infections won't respond to those drugs, but other medications may help with specific symptoms such as wheezing. Regardless of the source of the infection — virus or bacteria, resting and staying hydrated are key.

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Pulmonary edema, also known as fluid in the lungs, is another problem that can cause crackling in the lungs. According to the Mayo Clinic, heart problems, such as coronary artery disease, heart muscle damage and heart valve problems, are the most common source of this edema.

If the heart's pumping function is impaired—a condition known as congestive heart failure— blood can back up in the arteries between the heart and the lungs, says the U.S. National Library of Medicine. The resulting increased pressure leads to fluid leakage into the lungs, causing pulmonary edema.

Fluid accumulation leading to pulmonary edema may also be caused by pneumonia, chest trauma, altitude sickness or exposure to harmful materials or toxins, says Mayo Clinic. Pulmonary edema that develops suddenly can be fatal if not treated quickly, it cautions.

Approximately 32 million Americans have some form of obstructive lung disease, according to the American Lung Association (ALA). Asthma and COPD (chronic obstructive pulmonary disease) are the most common.

When someone has an obstructive lung disease, it can become increasingly difficult to breathe due to inflammation or an airway blockage, says the National Heart, Lung, and Blood Institute (NHLBI). Obstructive lung diseases typically cause wheezing, but can also cause lung crackles, mostly due to excess mucus in the airways from ongoing inflammation, explains Cedars-Sinai.

Shortness of breath and chronic cough are common with obstructive lung diseases, especially if not well controlled, explains NHLBI.

Interstitial lung diseases (ILD) encompass a large group of lung disorders that primarily involve abnormalities of the interstitium, the tissue that surrounds the air sacs in the lungs, reports the ALA. Ongoing ILD typically leads to scarring of the interstitium and lung stiffness. Once scarring occurs, it can't be undone. Most people with pulmonary fibrosis, a type of ILD, have crackles in their lungs, says the Pulmonary Fibrosis Foundation.

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