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What is Crescents are characteristically seen in and explain in detail?
Ans. b (RPGN) (Ref Robbins 7th/975; TABLE 20-6).Type I RPGN (Anti-GBM Antibody): Idiopathic; Goodpasture syndromeType II RPGN (Immune Complex): Idiopathic; Postinfectious; SLE; Henoch-Schonlein purpura (IgA)Type III RPGN (Pauci-lmmune): ANCA asso; Idiopathic; WG; Microscopic PAN/microscopic polyangiitisGlomerulopathiesDiseaseMost frequent presentationPathogenesisLight microscopyFluorescence microscopyElectron microscopyPoststrepto- coccal GNAcute nephritisAb mediated circulating or planted antigenDiffuse prolife- ration; leukocytic infiltrationGranular IgG and C3 in GBM and mesangiumSubepithelial humpsGoodpasture syndromeRapidly progressive GNAnti-GBM COL 4-A3 antigenProliferation; crescentsLinear IgG&C3 fibrin in crescentsNo deposits; GBM disruptions; fibrinIdiopathic RPGNRapidly progressive GNAnti-GBM ab. Immune complex. ANCA-asso. complex.Proliferation; focal necrosis; crescentsLinear lgG&C3 Granular IgG or IgA or IgM negative or equivocalNo deposits Deposits may be present.Membranous glomrulopathyNephrotic syndromeIn situ ab mediatd; antigen unkownDiffuse capillary wall thickeningGranular IgG and C3; diffuseSubepithelial depositsMinimal change diseaseNephrotic syndromeUnknown, loss of glom polyanion; podocyte injuryNormal; lipid in tubulesNegativeLoss of foot processes; no depositsFocal segmental glomerulo- sclerosisNephrotic syndrome; non- nephrotic proteinuriaUnknown, Ablation nephropathy Plasma factor (?); podpcyte injuryFocal and segmental sclerosis and hyalinosisFocal; IgM and C3Loss of foot processes; epithelial denudationMembrano- proiiferative GN (MPGN) Type INephrotic syndromeImmune complexMesangial proliferation; BM thickening splitting.(1) IgG + C3; Clq + C4(1) Subendothelial depositsDense deposit disease (MPGN Type II)Hematuria CRFAutoantibody; alternative complement pathway (II) C3 +- IgG; no Clq or C4(II) Dense depositsIgA nephropathyRecurrent hematuria or proteinuriaUnknown;Focal proliferative GN; mesangial wideningIgA +/- IgG, IgM, and C3 in mesangiumMesangial and paramesangial dense-depositsChronic GNCRFVariableHyalinized glomeruliGranular or neg