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594 SeCTIOn III Renal ` RENAL—PAthoLogy Renal ` RENAL—PAthoLogy
` RENAL—PAthoLogy
Casts in urine Presence of casts indicates that hematuria/pyuria is of glomerular or renal tubular origin.
Bladder cancer, kidney stones hematuria, no casts.
Acute cystitis pyuria, no casts.
RBC casts A Glomerulonephritis, hypertensive emergency.
WBC casts B Tubulointerstitial inflammation, acute pyelonephritis, transplant rejection.
Granular casts C Acute tubular necrosis (ATN). Can be “muddy brown” in appearance.
Fatty casts (“oval fat Nephrotic syndrome. Associated with “Maltese cross” sign D.
bodies”)
Waxy casts End-stage renal disease/chronic kidney disease.
Hyaline casts E Nonspecific, can be a normal finding. Form via solidification of Tamm–Horsfall mucoprotein
(secreted by renal tubular cells).
A B C D E
Nomenclature of glomerular disorders
tyPE ChARACtERistiCs EXAmPLE
Focal < 50% of glomeruli are involved Focal segmental glomerulosclerosis
Diffuse > 50% of glomeruli are involved Diffuse proliferative glomerulonephritis
Proliferative Hypercellular glomeruli Membranoproliferative glomerulonephritis
Membranous Thickening of glomerular basement membrane Membranous nephropathy
(GBM)
Primary glomerular 1° disease of the kidney specifically impacting Minimal change disease
disease the glomeruli
Secondary glomerular Systemic disease or disease of another organ SLE, diabetic nephropathy
disease system that also impacts the glomeruli
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