What type of inflammation is characterized by the formation of granulomas?

Granulomatous inflammation is a specific type of chronic inflammation defined by the formation of granulomas, which are organized aggregates of macrophages that transform into epithelioid cells. This type of inflammation typically arises in response to persistent irritants that the immune system cannot eliminate effectively, such as certain bacteria (e.g., Mycobacterium tuberculosis), fungi, or foreign materials.

Granulomas serve as a protective response, encapsulating disease-causing agents or irritating substances in an attempt to isolate them from healthy tissue. The presence of granulomas is indicative of a prolonged inflammatory process, and their formation is a hallmark of conditions such as sarcoidosis, tuberculosis, and Crohn's disease. Understanding the role of granulomas in chronic inflammation helps differentiate between types of inflammatory responses and their underlying causes.

In contrast, acute inflammation is characterized by rapid onset and involves the accumulation of neutrophils rather than the formation of granulomas. Chronic inflammation, while it encompasses granulomatous inflammation, also includes other forms without granuloma formation. Fibrinous inflammation primarily involves the deposition of fibrinogen and is associated with serous membrane irritation rather than granuloma formation. Thus, granulomatous inflammation is specifically defined by the presence of granulomas,