Case 18: Pathology

Case 18 Index

Great job, your patient tolerated the kidney biopsy well. It’s the morning afterwards and your pathologist shows you this Periodic Acid Schiff (PAS) stain.  Click here if you want some quick pathology tips.

Fibrocellular Crescent Formation and Interstitial Inflammation in Lupus Nephritis on PAS

Which of the following do you see above (more than one answer may be correct!)
Crescent formation
Excellent! We see extracapillary proliferation with obliteration of Bowman’s space. Crescents can be characterized as cellular (active disease), fibrous (chronic disease), or fibrocellular crescents. Here, we see fibrocellular crescent.
Endocapillary proliferation with obliteration of capillary loops
Correct! We can no longer visualize the capillary lumen due to endothelial cell proliferation.
Podocyte effacement
The podocyte structure is best visualized under electron microscopy, not light microscopy.
Subepithelial deposits
Subepithelial deposits are best seen under electron microscopy, not light microscopy.

Click here once you’re ready to look at some more images!

Case 18 Index
Case 18 Introduction
Case 18 Physical Exam

Case 18 Diagnostic Testing