Chronic pyelonephritis

Kidney nontumor
Bacterial infections
Chronic pyelonephritis

Author: Nikhil Sangle, M.D.

Topic Completed: 3 December 2012

Revised: 11 March 2019

Copyright: 2002-2019, PathologyOutlines.com, Inc.

PubMed Search: Chronic pyelonephritis [title] kidney

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Table of Contents

Cite this page: Sangle N. Chronic pyelonephritis. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/kidneychronicpyelo.html. Accessed January 27th, 2020.

Definition / general

Chronic tubulointerstitial inflammation and renal scarring with severe involvement of calyces and pelvis
Pyelocalyceal damage / blunting rules out other tubulointerstitial inflammation

Clinical features

Causes 10% - 20% of end stage renal disease in transplant or dialysis units
Associated with pyelitis and ureteritis cystica
Some patients with pyelonephritic scars develop focal and segmental glomerulosclerosis with proteinuria in nephrotic range, perhaps due to renal ablation nephropathy
Types: reflux (chronic reflux-associated pyelonephritis) and obstruction (chronic obstructive pyelonephritis)
Reflux: more common, usually arises in childhood, unilateral or bilateral; damage often due to infection; associated with calyceal dilation (usually upper pole); see tubular atrophy and thyroidization, interstitial fibrosis
Obstruction: associated with parenchymal scarring, usually not in children

Case reports

68 year old woman with renal sinus mass by imaging (J Med Case Rep 2009;3:9054)

Gross description

Irregular scarred cortical surface usually at poles, dilated and blunted calyces
Dilated ureter; retraction and destruction of papillae with "U” shaped scars

Microscopic (histologic) description

Tubular thyroidization (filled with colloid casts), tubular atrophy
Interstitial fibrosis and inflammation (intense diffuse lymphoplasmacytic inflammatory infiltrate with germinal centers)
Obliterative endarteritis of vessels, interstitial Tamm-Horsfall protein (amorphous, fibrillary, PAS+ material surrounded by inflammatory cells)
Normal glomeruli early in disease course

Microscopic (histologic) images

Images hosted on other servers:

Various images

Differential diagnosis

Chronic glomerulonephritis: diffusely scarred cortex
Vascular disease: can cause wedge-shaped cortical scars, but underlying medullary and calyceal areas are normal