Most of the time,<unk>  is not caused by an infectious agent. Histopathological changes are that of a chronic granulomatous disorder, characterized by fibrinoid necrosis, infiltration by polymorphonuclear cells, lymphocytes, plasma cells and macrophages. The granuloma is surrounded by multinucleated epitheloid giant cells and new vessels, some of which may show evidence of vasculitis.
Scleritis
Episcleritis
Periostitis
Corneal hydrops
Corneal neovascularization
Interstitial keratitis
Otosclerosis
Vasculitis