Case 17: Additional Pathology

Case 17 Index

Oops! Your pathologist tells you that the specimen that had been sent for EM processing is lost…but take a look at the immunofluorescence (IF) stain for IgG below:

Linear IgG Anti-GBM Disease_2

What do you see?
Granular basement membrane staining of IgG
We do see staining of the basement membrane, but it does not appear to be granular. Check out a granular IF stain below:
Linear basement membrane staining of IgG
Yes! This staining pattern should lead you straight to the final diagnosis.
“Full house” staining
“Full house” staining refers to granular IF staining of IgG, IgM, IgA, C3, and C1q. We only are given an IgG stain here which does not appear to be granular. Take another shot!
Negative IF
We do see some bright green staining here, making this a positive IF. Try again!
Mesangial staining of IgA
We do not see staining of the mesangium in this image. Mesangial staining would look like the image below. See the difference? Pick again!
It’s time to lock in your final diagnosis! Choose one before moving on to the end of this case.
Post-infectious glomerulonephritis (PIGN)
Membranous nephropathy
IgA nephropathy
Thrombotic microangiopathy (TMA)
Membranoproliferative glomerulonephritis
Granulomatosis with polyangiitis (GPA)
Acute interstitial nephritis (AIN)
Systemic lupus erythematosus (SLE) nephritis
Anti-glomerular basement membrane (GBM) disease
Acute tubular necrosis (ATN)

Click here if you’re confident in your final diagnosis!

Case 17 Index
Case 17 Introduction
Case 17 Physical Exam
Case 17 Diagnostic Testing
Case 17 Pathology