Microscopic polyangitis Necrotizing vasculitis with few or no immune deposits affecting small vessel(capillaries venules or arterioles). Necrotizing arteritis involving small and medium-size arteries may be present. Necrotizing glomeruLinephritis is very common. Pulmonary capillaritis often occurs Nephritis lung damageMicroscopic polyangiitis Necrotizing vasculitis , with few or no immune deposits ,affecting small vessel (capillaries , venules or arterioles) . Necrotizing arteritis involving small and medium-size arteries may be present. Necrotizing glomerulnephritis is very common. Pulmonary capillaritis often occurs. Nephritis lung damage