Pathological Finding:
Kidney biopsy (Figure.3, A-C) showed 24 glomeruli, 23 glomeruli show extra capillary cellular crescents, but none show fibro cellular/fibrous crescents. The crescents are temporally homogenous at the same age and stage and fill the space delineated by Bowman’s capsule (Figure.3, A-B), some show rupture of Bowman’s capsule. Some glomeruli show active periglomerular inflammation (Figure.3, A). Mild tubular atrophy and interstitial fibrosis were also noted (10-15% of the cortical tissue), associated with moderate multifocal interstitial inflammatory infiltrate composed of lymphocytes and occasional eosinophils. Direct immunofluorescent microscopy showed linear staining of IgG (Figure.3, C), complement component C3, and light chains (kappa and lambda) along the glomerular basement membrane. These findings of Crescentic glomerulonephritis are consistent with Anti-Glomerular Basement Membrane (GBM) glomerulonephritis.