Feature of microscopic polyangitis is -

Ans. is 'c' i.e., Renal involvementMicroscopic polvangitis (MPA)It is a necrotizing vasculitis.o It is considered as a variant of polyaeritis nodosa (PAN), but in contrast to classical PAN, microscopic polyangitis involves smaller vessels, i.e. aerioles, venules and capillaries.o It is also differentiated from classical PAN by ?It involves lung (in classical PAN lungs are not involved).In kidney it causes glomerulonephritis (in classical PAN, glomerulonephritis is absent).In skin it causes manifestation due to small vessel involvement, i.e. palpable purpura, while classical PAN has manifestation of medium vessel involvement i.e digital ischemia and gangrene, livido reticulars, nodules, papules.It is positive for p-ANCA, while classical PAN is not associated with ANCA.Presentationo Constitutional symptoms Fever, weight loss, malaise and fatigue.o Kidney (most common organ involved). There is rapidly progressive glomerulonephritis. The glomerulonephritis is pauci-immune, i.e. there is no immunoglobulin or complement deposition. Renal hypeension does not occur, in contrast to classical PAN, where hypeension is the prominant feature of kidney involvement.o Lung Lung involvement can be dramatic and life threathing. Capillaritis causes alveolar hemorrhage. Hemoptysis, pleuritis and interstitial fibrosis.o Skin Features of small vessel involvement, i.e. purpura, papule. Involves the dependent area of the body, i.e. feet & leg.Peripheral nervous system --> Mononeuritix multiplexUpper respiratory tract --> Rhinitis, sinusitis, otitis mediao Musculoskeletal system --> Myalgia, aralagia, Non-destructive migratory ahritiso Eye ----> Conjuctivitis, episcleritisNoteMicroscopic polyangitis has same spectrum of manifestations as wegner's granulomatosis, but can be differentiated it by following two features ?In wegner's granulomatosis there is granulometous vasculitis i.e. granuloma formation, granulomas are absent in MPA.Wegner's granulomatosis causes nodules and cavity in the lung.