What is A female who presented with cough with bloody sputum is diagnosed of having granulomatosis with polyangitis. Which of the following is the characteristic histological feature of granulomatosis with polyangitis: and explain in detail?
Granulomatosis with polyangiitis (Wegener's granulomatosis):Three pathologic hallmarks of are granulomatous inflammation, vasculitis, and necrosis.Classic triad of upper and lower respiratory tract disease and glomerulonephritis.The histopathologic hallmarks of granulomatosis with polyangiitis are necrotizing vasculitis of small aeries and veins together with granuloma formation, which may be either intravascular or extravascular.Lung involvement typically appears as multiple, bilateral, nodular cavitary infiltrates, which on biopsy almost invariably reveal the typical necrotizing granulomatous vasculitis.In its earliest form, renal involvement is characterized by a focal and segmental glomerulitis that may evolve into a rapidly progressive crescentic glomerulonephritis.Granuloma formation is only rarely seen on renal biopsy.In contrast to other forms of glomerulonephritis, evidence of immune complex deposition is not found in the renal lesion of granulomatosis with polyangiitis. Ref: Langford C.A., Fauci A.S. (2012). Chapter 326. The Vasculitis Syndromes. In D.L. Longo, A.S. Fauci, D.L. Kasper, S.L. Hauser, J.L. Jameson, J. Loscalzo (Eds), Harrison's Principles of Internal Medicine, 18e.