Non-necrotizing granulomatous inflammation is a term pathologists use to describe a pattern of chronic (long-standing) inflammation. A granuloma is a small, round collection of specialized immune cells that stick together to both surround and remove a harmful agent from the body. The immune cells in a granuloma include lymphocytes, histiocytes, and multi-nucleated giant cells. The histiocytes in a granuloma are described as “epithelioid” because they stick together in a way that is similar to epithelial cells. The term non-necrotizing refers to the absence of dead cells in the centre of the granuloma. In contrast, a necrotizing granuloma has dead cells at its centre.
Non-necrotizing granulomas may be seen in a variety of medical conditions including sarcoidosis, inflammatory bowel disease (in particular Crohn’s disease), rheumatoid arthritis, and infections. Non-necrotizing granulomatous inflammation may also be seen in association with foreign material such as sutures, wood splinters, and tattoo ink.