Necrotizing granuloma

An inflammatory lesion characterized by central coagulative or caseous necrosis surrounded by epithelioid histiocytes, multinucleated giant cells and lymphocytes. It is formed when the body tries to wall off harmful substances, resulting in a core of dead and decaying tissue. Possible causes are infections (Tuberculosis, Histoplasma, Aspergillus, Blastomyces, Cat-scratch disease, Tularemia, Nontuberculous mycobacterial infections), Granulomatosis with Polyangiitis (Wegeners granulomatosis), rheumatoid arthritis, and lymphoma.