Pathology of Nephritic Syndrome

Question 1

most of the tubules are in the _______ (medulla/cortex). In that region ____% is tubule

Answer 1

cortex.

70%

Question 2

Why is vasculature especially a bad thing in the kidney?

Answer 2

The arteries in the kidney are all end-arteries. They don’t connect to each other and so a vasculature disease or an emboli can kill alot of kidney.

Question 3

The Basement Membrane forms the capillaries and that basement membrane is contiguous with what other structure?

Answer 3

Bowmans capsule.

Question 4

There are two types of nephron for the most part what are they and what supplies blood to each?

Answer 4

superficial cortical nephron- forming the PCT and the DCT (supplied by the peritubular capillary network)

Juxtamedullary nephron- forming the Loop of Henle (supllied by the Vasa Recta)

Question 5

RBC casts indicate what syndrome?

Answer 5

Nephritic syndrome

Question 6

Adjacent foot processes come from ______(the same/a different) podocyte.

Answer 6

a different

Question 7

Acute nephritic syndrome includes what major characteristics?

Answer 7

• inc glomerular capillary permeability ( causes hematuria and proteinuria)
• dec. GFR (causes edema (from Na, H2O retention), azotemia (elevated BUN), and hyperkalemia

Question 8

What are the 4 morphologic glomerular changes that accompany glomerular injury (basically what are four ways the glom shows injury)? Describe each.

LEARNING OBJECTIVE

Answer 8

1. cell proliferation- we will see hypercellularity in either the mesangial, endocapillary, or epithelial (podocyte) cells (this last one leads to crescents).
2. Leukocyte infiltration (ask yourself if there are polymorphonuclear cells in the glomerulus).
3. BM membrane thickening/ changes (sometimes you can’t tell on light microscopy and need EM to tell).
4. Sclerosis (scarring)– can be segmental or global, and diffuse or local.

Question 9

Characterization of Glomerular Disease (GD):

• What clinical data can we gather to characterize GD?
• What morphological data?
• Pathogenic data?

Answer 9

• clinical- determine whether nephritic or nephrotic.
• morpho.- light microscopy
• patho.- Immunofluorescence (IF), Electron microscopy (EM), and serology (usually refers to identifying antibodies in the serum).

Question 10

What kind of things are we looking for in immunofluorescence?

Answer 10

characterization of immunopathogenesis. Decide whether the disease is associated with:

• Igs or complement
• mesangial distribution (looks like a burning bush) or capillary distribution
• linear pattern or granular (lumpy bumpy) pattern (indicates an immune complex problem.

Question 11

What are we looking for in EM?

Answer 11

mostly just deposits of Antigen-antibody complexes and glomerular basement membrane changes.

Question 12

What are we looking for in serology?

Answer 12

complement levels
ANA (found in Lupus)
ANCA (anti-neutrophil cytoplasmic antibodies- associated with Wegener’s)

Question 13

Which glomerular diseases are immune complex mediated (cause granular staining)? Which are anti-body mediated (cause linear staining)? And which cause no staining?

LEARNING OBJECTIVE

Answer 13

immune complex:

• IgA
• Lupus
• Endocarditis
• idiopathic

anti-body:

• Goodpasture’s syndrome
• Anti-GBM

No Staining;
-all the “pauci immune” diseases (like Wegner’s,Churg Strauss etc. don’t worry about the specifics on this one)

Question 14

What nephritic diseases were talked about?

Answer 14

1. Benign familial hematuria (thin BM disease)
2. Alport’s Disease
3. IgA nephropathy
4. Postinfectious GN
5. Focal necrotizing/crescentic GN
6. Lupus GN

NOTE: the first two are not nephritic diseases strictly speaking. They are hereditary disorders that can often look like nephritic diseases.

Question 15

What is Thin Membrane Disease. What do we do about it?

Answer 15

this is a hereditary disorder that causes extra thin membranes. Also known as benign familial hematuria bc it can cause hematuria from the skinny membranes. diagnose it based on EM.

Has a very good prognosis. Don’t need to do anything

Question 16

What is Alport’s disease. What are some characteristic findings we can use to distinguish it from Thin membrane disease?

Answer 16

Another hereditary disease that mimics kidney disease (it can lead to end stage renal disease however). This one can’t form normal basement membranes. The definitive diagnosis is made based on finding a basketweave pattern of BMs on EM.

You see three things at once with Alports– nephritis, deafness, and ocular lesions.

Question 17

Besides Thin Membrane Disease and Alport’s disease, the other diseases we talk about are all types of proliferative glomerulonephritis. The main hallmark of proliferative glomerulonephritis is hypercellularity. What kinds of hypercellularity do we see?

Answer 17

• endocapillary (occlusion of capillary loops)
• mesangial
• epithelial (this is where we see crescents– form from injury to glomerular capillaries. so it can be caused by any disease severe enough to tear glomerular capillaries)
• inflammatory cells (not really a type of hypercellularity

Question 18

IgA nephropathy:

1. what is its classic presentation?
2. what morphologic data is seen?
3. What pathogenic data is seen?
4. What is therapy?

Answer 18

1. gross microscopic hematuria
2. LM: mesangial involvement
3. EM: mesangial deposits; IF: Mesangial IgA
4. steroids (sometimes works sometimes doesn’t)

Question 19

What is Henoch-Schonlein Purpura?

Answer 19

a systemic form of IgA vasculitis.

Often occurs post URI.

Question 20

Postinfectious Glomerulonephritis;

1. what is its classic presentation?
2. what morphologic data is seen?
3. What pathogenic data is seen?
4. what therapy is given?

Answer 20

1. usually occurs post-streptococcal infections
2. It is an immune complex disease- the antigen is SpeB (this is important bc it is cationic and the glomerulus is negatively charged so makes sense why it would stick there).
3. EM: subepithelial hump-like deposits
   IF: Granular Glom. BM (called starry sky pattern)
   Serology: elevated ASO
4. supportive (these tend to recover on their own- children recover better than adults though

Question 21

What is the difference between Goodpasture’s disease and anti-GBM disease? What is Anti-GBM Disease?

Answer 21

both involve IgG that attacks the glomerulus. If its just the kidneys involved then its Anti-GBM disease. If the kindeys and lung are involved then its Goodpastures. Classic presenation of both is RPGN (rapidly progressive glomerular nephritis).

Question 22

Crescentic GN

1. what is its classic presentation?
2. what morphologic data is seen?
3. What pathogenic data is seen?
4. what therapy is given?

Answer 22

1. usually RPGN
2. Crescents
3. Variable causes:
   - immune complex
   - anti-GBM
   - systemic disease (can be pauci immune, vasculitis, SLE)
   - idiopathic
4. variable depending on cause (don’t use cytotoxics if patient has endocarditis though)

Question 23

Lupus Nephritis

1. what is its classic presentation?
2. what morphologic data is seen?
3. What pathogenic data is seen?
4. what therapy is given?

Answer 23

1. variable
2. variable
3. Endogenous immune complex (ANA’s)
   - IF: “full house” (means you get everything- IgG, IgA, IgM, C3, C1q)
   - Serology: ANA, anti-dsDNA
4. steroids, cytotoxics