A calcified granuloma is a cluster of cells that forms as part of an immune response and hardens over time. It’s usually due to an infection and most commonly forms in the lungs, but can occur in many places and for several causes.

During an infection, immune cells surround and isolate foreign material, such as bacteria. This cluster of cells is called a “granuloma.” They most commonly occur in the lungs but can affect other organs throughout your body, including your:

  • skin
  • lymph nodes
  • eyes
  • liver
  • spleen

When something is “calcified,” it means it contains calcium deposits. The element calcium tends to collect in tissue that is healing.

Calcified granulomas don’t usually cause problems, but it’s important to treat the underlying causes. Keep reading to learn what can cause calcified granulomas, how doctors detect them, and what the next steps might be.

Not all granulomas are calcified. Granulomas are spherical clusters of cells that surround inflamed tissue. They can eventually calcify.

A calcified granuloma has a similar density to bone and will appear brighter than the surrounding tissue on an X-ray.

Since noncalcified granulomas don’t contain calcium deposits, they can appear as a less distinct clump of cells on an X-ray or CT scan. Because of this, doctors often initially misdiagnose them as cancerous growths when viewed in this manner.

If you have a calcified granuloma, you may not even know it or experience any symptoms. Typically, a granuloma will only cause symptoms if it’s affecting an organ’s ability to function properly due to its size or location.

If you have a calcified granuloma and are experiencing symptoms, it may be due to an ongoing underlying condition that caused it to form. For example, infectious granulomas may produce symptoms related to the infection, such as fever, cough, or abdominal pain.

In some cases, granulomas may form on the skin. Depending on the cause, these can take on various appearances.

Granulomas develop as part of an immune response, often due to an infection. Common infectious causes include:

Although not a cause, HIV is a known risk factor for many of the infections that can lead to calcified granulomas, especially in the spleen.

However, noninfectious causes of inflammation can also cause granulomas. Examples include:

Persistent inflammation can lead to calcification. That’s because inflammation triggers specific proteins that cause calcium to bind. Extensive fibrosis (scarring of tissue) may also play a role in what causes some granulomas to calcify.

People with calcified granulomas may not even know they have them. Doctors often discover noninfectious granulomas incidentally during an imaging procedure such as an X-ray or CT scan.

If a doctor discovers an area of calcification, they can use imaging technology to evaluate the size and pattern of calcification to determine if it’s a granuloma.

Calcified granulomas are almost always benign. However, less commonly, they can become surrounded by a cancerous tumor.

A doctor may also perform additional tests to determine what has caused the granulomas to form. For example, if they discover calcified granulomas in your liver, a doctor may ask about your medical and travel history.

They may also perform laboratory tests to evaluate your liver function. If needed, they can take a biopsy to confirm an underlying condition that has caused granuloma formation.

Since calcified granulomas are almost always benign, they typically don’t require treatment. However, if you have an active infection or condition that’s causing granuloma formation, a doctor will work to treat that.

If you have an active bacterial or fungal infection, your doctor will prescribe an appropriate antibiotic or antifungal. They can also prescribe praziquantel, an antiparasitic drug, to treat schistosomiasis.

Doctors treat noninfectious causes of granulomas, such as sarcoidosis, with corticosteroids or other immunosuppressive drugs to control inflammation.

Complications from granuloma formation are often due to the underlying condition that caused them.

Granuloma formation can sometimes disrupt tissue function. For example, the parasitic infection schistosomiasis can cause granulomas to form around the parasite’s eggs in the liver, which can, in turn, lead to fibrosis of the liver. This is when excess connective tissue accumulates into scar tissue in the liver, disrupting liver structure and function.

If you have an active infection or other condition that leads to granulomas, it’s very important to treat it to prevent any complications.

If you have one or more calcified granulomas, chances are you don’t know you have them. If a doctor notifies you that you have a calcified granuloma, you will likely not require treatment for the granuloma itself.

If you have an underlying condition or infection that’s leading to granuloma formation, your doctor will work to treat that. Your outlook will depend on the condition requiring treatment. Your doctor will work with you to establish a treatment plan and address any concerns.

Granulomas develop as part of an immune response to an infection or other trigger. The cluster of cells attempts to close off the infection. Over time, the cell cluster can harden due to calcification.

These calcified clusters usually don’t cause symptoms and usually aren’t a cause for concern. However, they may be a sign of more extensive scarring.

Doctors usually discover granulomas incidentally on imaging tests. They can run other tests to determine the cause. Treating the responsible condition will ultimately be more important.