<prompt> A 22 year old presents to his physician with hemoptysis and hematuria with basement membrane antibodies. Most likely diagnosis is -Wagners granulomatosisGood pastures syndromePANChurg-strauss syndrome  <response>: Ans. is b i.e., Good pastures syndrome o Good pastures syndrome is an autoimmune disease characterized by formation of anti GBM antibodies that attack both pulmonary capillaries and the glomerulus GBM.Good pastures syndromeAntibodies against non collagenous domain NCL of a3 chain of collagen type IVFound in Glomerular basement membrane pulmonary capillariesDamage to basement membrane of glomeruli and pulmonary capillaryAntibodies aganist glomerularAntibodies against pulmonary capillariesBasement membrane GBM Glomerulonephritis Renal diseasePulmonary manifestationso Features of acute glomerulonephritis RPGNo Hemoptysis frank HematuriaHemoptysis is largely confined to smokers Proteinuriao Dyspnea FdemaX-ray finding Rapidly progressive renal failureo Diffuse bilateral pulmonary infiltrateso Pathology o Diffuse crescenteric glomerulonephritis Linear IgG staining along basement membrane on immunofluorescence Laboratory features in Good pastures sy ndromeo Circulating anti GBM antibodies IgG : Positiveo A MCA antibodies : Typically negative May be present in upto 30o ANA antibodies : Usually normalo C3 lesels : Usually normal 