Case 35: Additional Pathology -

Your pathologist informs you the additional slide preparations are ready! Take a look below…

EM (Electron Microscopy)

Where do you see the majority of deposits in the electron microscopy above?

There are no deposits.

Try again! We see dark gray, dense material (deposits) in the electron micrograph above.

Mesangial deposits

We don’t actually see the mesangial space here and thus cannot identify mesangial deposits. Pick again!

Subendothelial deposits

The majority of these deposits are not in the subendothelial space, take another look!

Subepithelial deposits

Correct!

Here’s another stain:

What stain do you see above?

Jones Methamine Silver Stain

Correct! Collagen appears black with this stain. In this disease process, we see the “spike and hole appearance.” The “spikes” of basement membrane are seen as black, while the deposits (“holes”) do not pick up the stain. These “holes” may give the basement membrane a “bubbly” appearance.

Periodic Acid-Schiff (PAS) Stain

In a PAS stain, collagen appears magenta. Pick again!

Immunohistochemistry (IHC) stain for PLA2R

This is not an IHC stain. When an IHC stain is positive, the antigen of interest should appear brown. Try again!

Masson’s Trichrome Stain

This stain is used to visualize fibrosis. The colors in a Masson’s Trichrome stained slide should appear tones of red and blue. Pick again!

We’re almost there! Take a look at the immunofluorescence stains below (click!)

IgG