What are the causes of granulomatous inflammation?

The main causes of granulomatous inflammation include the following: 1. Infectious factors: Such as bacterial infections (e.g., Mycobacterium tuberculosis, Mycobacterium leprae), fungal infections (e.g., Histoplasma capsulatum, Cryptococcus neoformans), and parasitic infections (e.g., Schistosoma). After invading the body, these pathogens can stimulate the body's immune response, leading to granuloma formation. 2. Autoimmune abnormalities: Such as granulomatosis with polyangiitis and allergic granulomatosis, which are caused by abnormal immune responses of the body. 3. Foreign body stimulation: Including both endogenous and exogenous foreign bodies, such as urate crystals in gout nodules, surgical sutures, and talc powder. These foreign substances may trigger an immune response after entering the body, leading to granulomatous inflammation. 4. Other causes: Such as sarcoidosis, a multisystem granulomatous disease of unknown cause, which may be related to multiple factors including genetic predisposition and infections.