Case 6: Additional Pathology

Case 6 Index

Finally, some additional slide preparations are ready! Take a look below…

EM (Electron Microscopy)
Mesangial Immune Complex Deposits in IgA Nephropathy_3.jpg

Which of the following do you see above?
Subepithelial hump-like deposits
We don’t see any deposits in the basement membrane here, try again!
Subendothelial deposits
 We don’t see any deposits in the basement membrane here, try again!
Thin basement membrane
 It appears to be a normal width here. The normal width is near 300 nm.
Duplication or “tram-tracking” of the basement membrane
The basement membrane appears to be intact here, with only one layer visible. Try again!
Mesangial deposits
You got it! We see dense deposits in the mesangial space, between the capillary loops.
Which of the following would you be most likely to see on immunofluorescence (IF) for this patient?
Granular basement membrane staining of IgG
We see dense deposits in the mesangial space here, so it would be less likely to find granular IF staining of the basement membrane.
Linear basement membrane staining of IgG
We would see this pattern in a patient with anti-glomerular basement membrane disease, and would not expect mesangial deposits as we see in this patient. Try again!
Negative IF
We see mesangial deposits above, implying the presence of immune-complex deposits. Negative IF would suggest the absence of immune complex deposits.
Mesangial staining of IgA
Correct! Take a look below and notice that the basement membrane does not appear fluorescent:

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

Case 6 Index
Case 6 Introduction
Case 6 Physical Exam
Case 6 Diagnostic Testing
Case 6 Pathology