<prompt> In Wegeners glomerulonephritis characteristic feature seen inGranuloma in the vessel wallFocal necrotizing glomerulonephritisNodular glomerulosclerosisInterstitial granuloma  <response>: Focal necrotizing glomerulonephritis Ref. Harrison 17the p. 2121; Bobbins 8the p. 5161 Wegeners granulomatosis is a distinct clinicopathologic entity characterized by granulomatous vasculitis of the upper and lower respiratory tracts together with glomerulonephritis. The histopathological hallmark of Wegeners granulomatosis is necrotizing vasculitis of small aeries and veins together with granuloma formation which may be either intravascular or extravascular. An impoant point to note, Though it is called granulomatous vasculitis:? - Granulomas in Wegeners granulomatosis are seen only in lungs or respiratory tract. Granuloma formation is rarely seen in other organs. Other organs, only demonstrate necrotizing vasculitis. So Wegeners granulomatosis can also be defined as Granulomatous vasculitis of the upper and lower respiratory tracts together with glomerulonephritis. Bobbins defines Wegeners granulomatosis as necrotizing vasculitis not granulomatous vasculitis. According to Robbins Wegeners granulomatosis is a necrotizing vasculitis characterized by a triad of :? - Acute necrotizing granuloma of upper respiratory tract ear, nose, sinuses, throat or the lower respiratory tract. - Necrotizing or granulomatous vasculitis affecting small to medium sized vessels e.g. capillaries, venules, aeriole and aeria most prominent in the lungs and upper airways but affecting other sites as well. - Renal disease in the .form of focal necrotizing often crescenteric glomerulonephritis. Glomerulonephritis in Wegeners granulomatosis Wegeners glomerulonephritis is characterized by focal and segmental necrotizing glomerulonephritis. That may evolve into a rapidly progressive crescenteric glomerulonephritis. Granuloma. formation is rarely seen in Wegeners glomerulonephritis. 