Pathology of the urinary system

INTERSTITIAL (TUBULOINTERSTITIAL) NEPHRITIS

 

 

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The tubules and interstitium are intimately associated, and damage to one affects the other. 

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inability in reabsorption, concentration and/or excretion of glomerular filtrate is the hallmark of 

interstitial nephritis. 

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interstitial nephritis can have a (multi-) focal or diffuse distribution. 

 

1) Multifocal Interstitial Nephritis

 

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a common, often incidental, finding in animals. 

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often visible grossly: few or many white foci randomly distributed in the cortex and medulla. 

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microscopically, these foci consist of aggregates of lymphocytes and plasma cells within the 

interstitium. 

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in severe cases, interstitial inflammation progresses to fibrosis and tubular atrophy. 

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multifocal interstitial nephritis is presumably the result of a resolved bacteremia or septicemia; e.g., 

in young calves, "white spotted kidney" is presumed to represent residual lesions of a neonatal 

E. 

coli

 sepsis. 

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also seen in malignant catarrhal fever, porcine circovirus infection, porcine leptospirosis, visceral 

larva migrans.