<prompt> Which of the following conditions are associated with paucity - immune crescentic glomerulonephritis?Henoch - Schonlein NephritisLupus Nephritis SLEMicroscopic polyangitisNephritis in Alpos syndrome  <response>: Microscopic polyangiitis is an ill-defined autoimmune disease characterized by a systemic, pauci-immune, necrotizing, small-vessel vasculitis without clinical or pathological evidence of necrotizing granulomatous inflammation. It is type III Rapidly progressive glomerulonephritis RPGN. Around 90 patient s will have P-ANCA positive. Ref: Emil A. Tanagho, Jack W. McAninch 2004, Chapter 31, Diagnosis of Medical Renal Diseases, In the book, Smiths General Urology, USA, Page 523; Robbins Basic Pathology, 7th Edition, Page 977 