A calcified granuloma in the lung is a cluster of immune cells with calcium deposits. They can be asymptomatic or cause symptoms such as wheezing and chest pain.

A granuloma is a small cluster of white blood cells and tissues. Granulomas can form in the lungs, as well as other areas of the body, such as the head, skin, or liver.

Granulomas are benign and not cancerous. Inflammation, infections, or foreign objects may cause granulomas to form.

Sometimes, a granuloma may calcify. This means calcium deposits collect in the granuloma, causing it to harden.

This article looks at the symptoms, causes, diagnosis, treatment, and outlook for calcified granulomas in the lungs.

A doctor looking at medical imaging of a person's lungs to identify calcified granulomas -1Share on Pinterest
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Typically, granulomas do not cause any symptoms.

However, some calcified granulomas in the lungs may cause symptoms, but this depends on the underlying cause. Some symptoms may include:

According to a 2017 review, lung granulomas may occur from infections such as:

Non-infectious diseases which may cause lung granulomas include:

Rarely, immunotherapy drugs cause granulomas. One such case study reports the drug pembrolizumab reactivating a lung granuloma.

According to a 2021 article, calcification of a granuloma may occur if the granuloma has extensive fibrosis. Fibrosis is a scarring or thickening of tissue.

In rare cases, calcified lung granulomas may occur with pneumocystis jirovecii pneumonia (PJP), a type of pneumonia from fungi.

Can COVID-19 cause granulomas?

According to a 2021 article, the SARS-CoV-2 virus may trigger certain responses in the body, which cause granulomas to form.

The research suggests that granulomas may form due to the body’s effective response to COVID-19 to prevent severe or life threatening illness.

A 2022 case report and review notes a case study in which a person who had recovered from severe COVID-19 infection developed sarcoidosis, which causes granulomas to form in the lungs and lymph nodes.

The research suggests that changes in the immune system play a role in the two conditions.

Any factors or conditions that increase the risk of infections or can cause granulomas may increase the risk of calcified lung granulomas.

For example, sarcoidosis is an inflammatory condition that causes granulomas to form in the lungs and chest lymph nodes. Risk factors for sarcoidosis include:

  • being older than 55 years
  • working with insecticides, mold, or substances that may cause inflammation
  • having a family history of sarcoidosis
  • taking certain HIV medications or monoclonal antibodies
  • being of African or Scandinavian descent
  • being female

According to older research from 2010, TB is a common cause of calcified granulomas in the chest, including in the lungs.

Risk factors for TB include:

  • close contact with a person with TB
  • a weakened immune system

Exposure to non-tuberculous mycobacteria (NTM) is a risk factor for lung granulomas.

Mycobacteria can occur in soil and water. Factors that may increase the risk of a mycobacterial infection include:

To diagnose calcified lung granulomas and differentiate them from other conditions, doctors may carry out the following:

Calcified granulomas are benign and often do not cause symptoms, so not all will require treatment. However, a doctor may need to treat the trigger or underlying cause of the granulomas.

For example, treatment for sarcoidosis may include reducing inflammation with medications such as corticosteroids.

Although granulomas may have similarities to cancerous growths on imaging scans, the Journal of Thoracic Disease states that calcification of a lung nodule usually indicates a benign growth.

Treatment and recovery time may depend on the underlying cause and the presence of symptoms. Treatment may help prevent complications, such as breathing difficulties or lung damage.

Calcified granulomas in the lungs are clusters of immune cells which contain calcium deposits. Infections, inflammation, or foreign objects may lead to calcified lung granulomas.

Calcified lung granulomas are benign, but sometimes, they cause scarring of the lungs or breathing problems.

Treatment can help to treat the underlying infection or inflammation and help prevent complications.