Pathology illustrations. Intraluminal LC casts with the typical appearance. By light microscopy: (A) sharp-edged periodic acid–Schiff negative casts surrounded by a cellular reaction (magnification ×600), (B) fractured cast on trichrome stain (magnification ×600), (D) eosinophilic granular casts on hematoxylin and eosin stain (magnification ×400), and (E) multinucleated giant cell reaction around a fractured cast (magnification ×400). By immunofluorescence: (C) positive staining with anti-κ (magnification ×100) and (F) negative staining with anti-λ (magnification ×100). Images of pathology features that were recorded: (G) extensive interstitial fibrosis and tubular atrophy with scarce mononuclear interstitial inflammation (periodic acid–Schiff, magnification ×100), (H) tubular rupture with the interruption of the tubular basement membrane (arrow) (Jones methenamine silver, magnification ×400), (I) interstitial giant cells (arrow) (periodic acid–Schiff, magnification ×400), (J) interstitial inflammation with tubulitis (arrow) (periodic acid–Schiff, magnification ×600), (K) THP extravasation into the interstitium (asterisk) (periodic acid–Schiff, magnification ×200), and (L) THP protein in the Bowman’s space (asterisks) (periodic acid–Schiff, magnification ×400).