| b) Gross Lesions
∙
acute:
-
kidneys are swollen and may have a wedge-shape red discoloration ascending from medulla
to cortex;
-
necrotizing papillitis (irregular borders) and a mucopurulent exudate are often visible in the
pelvis;
-
in severe cases, the exudate ascends to, and is visible through, the renal capsule.
∙
chronic:
-
marked renal scarring and fibrosis;
-
imperative to check the ureter and bladder since infection most likely originates there;
-
distended ureter with a purulent exudate is called pyoureter.
c) Microscopic lesions
∙
acute: necrosis and exfoliation of tubular epithelium with neutrophils and bacteria in the tubular
lumina.
∙
chronic: white bands of scar tissue extending from cortex to medulla, interstitial fibrosis, loss of
tubules, and, finally, "end stage kidney."
|
