Published: 18 Jun 2025

ICD9: 686.1      ICD10: L92.9      ICD11: 4A00.0Y

"Granuloma" and "Granulomatous" refer to a specific type of inflammation.
Here's a breakdown:

Granuloma: A granuloma is a small, nodular (lumpy) collection of immune cells. It's essentially a wall of inflammatory cells that the body builds to try and contain a substance it can't eliminate. Think of it like a tiny fortress around a foreign invader.

Granulomatous: "Granulomatous" is an adjective that means "characterized by granulomas" or "related to granulomas." For example, "granulomatous inflammation" means inflammation that involves the formation of granulomas.

Key Components and Characteristics of a Granuloma:

Macrophages: These are the main cells in a granuloma. They are a type of white blood cell that engulfs and digests foreign materials.
Epithelioid cells: Macrophages can transform into larger, flattened cells called epithelioid cells. These cells are often a prominent feature of granulomas.
Giant cells: Sometimes, several macrophages fuse together to form a giant cell. These cells can have multiple nuclei and are often found in granulomas.
Lymphocytes: These are another type of white blood cell that can be present in granulomas.
Fibroblasts: In some cases, fibroblasts (cells that produce collagen) may also be present, leading to fibrosis (scarring) around the granuloma.
Necrosis: Some granulomas have a central area of necrosis (tissue death). This is often referred to as "caseous necrosis" when it has a cheese-like appearance, a characteristic feature of tuberculosis.

Causes of Granulomas:

Granulomas form in response to a variety of triggers, including:

Infections:
Bacterial: Tuberculosis (TB), leprosy, syphilis
Fungal: Histoplasmosis, blastomycosis, coccidioidomycosis
Parasitic: Schistosomiasis
Foreign substances:
Sutures, talc, splinters
Autoimmune disorders:
Sarcoidosis, Crohn's disease, Granulomatosis with Polyangiitis (Wegener's)
Unknown causes:
Some granulomas form for reasons that are not yet fully understood.

Clinical Significance:

Granulomas can affect virtually any organ in the body, leading to a wide range of symptoms depending on the location and size of the granulomas. They are important because:

They indicate a specific type of inflammatory process. Identifying granulomas helps narrow down the possible causes of a disease.
They can cause organ damage. If granulomas are large or numerous, they can disrupt normal tissue function.
They may be a sign of a serious underlying condition. It's important to determine the cause of granulomas so that appropriate treatment can be initiated.

Diagnosis:

Granulomas are usually diagnosed by:

Biopsy: A small sample of tissue is taken and examined under a microscope.
Imaging studies: X-rays, CT scans, and MRI scans can help identify granulomas in certain organs.
Laboratory tests: Blood tests and other laboratory tests can help identify the underlying cause of the granulomas.

Treatment:

Treatment depends on the underlying cause of the granulomas. Options may include:

Antibiotics: For bacterial infections like TB.
Antifungal medications: For fungal infections.
Corticosteroids: To reduce inflammation.
Immunosuppressants: For autoimmune disorders.
Surgery: In some cases, surgery may be necessary to remove granulomas that are causing significant problems.

In summary: A granuloma is a specific type of inflammation characterized by a collection of immune cells, usually formed in response to a persistent irritant or infection that the body is trying to contain. Identifying granulomas is important for diagnosis and treatment of a variety of conditions.