Nephritic Disorders Flashcards
Nephritic disorders with NORMAL complement levels
- IgA nephropathy/HSP (henoch schonlein purpura)
- Alport’s
- SLE I, II, V
Nephritic disorders with LOW complement levels
- PSGN
- membranoproliferative glomerulonephritis (MPGN)
- SLE III, IV
Episodes of gross hematuria associated with viral respiratory illness or GI illness, is most likely due to ________
IgA nephropathy
To suspect IgA nephropathy, look for gross hematuria associated with _________
Upper respiratory tract infection or GI illness
Describe the presentation of someone with HSP (henoch Schonlein purpura)
Child with purpuric rash that starts at feet and goes upward and also has hematuria; it is a type of vasculitis
What conditions are associated with IgA nephropathy
- hepatic cirrhosis
- gluten enteropathy
- HIV
- minimal change disease
- ankylosing spondylitis
- malignancy
The damage of the glomeruli in IgA nephropathy is due to the IgA immune complexes that activate complement found in _______________
Glomerular mesangium
What are you most likely to see in IF in someone with IgA nephropathy?
Dominantly IgA deposits in the mesangium (can also see C3 and can also be seen in subendothelium)
PSGN manifests usually 10 days following _______ and 3 weeks following _______
Pharyngitis; impetigo
What are the complement levels in PSGN?
LOW
Elevated titers of _____________ and __________ and __________ complement are indicative of PSGN
Anti-streptolysin O; anti-DNAase B; LOW
↑ antistreptolysin O antibody or ↑ anti DNAase B with low complement is most likely indicative of what renal disease?
PSGN
Initially in PSGN, there are __________ IC deposits leading to activation of complement with resulting in _________
subendothelial; ↓ GFR
Subepithelial humps are characteristics for ________
PSGN
What is the rate of resolution of proteinuria in PSGN and why?
SLOW; bc IC deposits are cleared very slowly
What are some features of PSGN you’d see on light microscopy?
- hypercellular glomeruli
- proliferation of mesangial, endothelial and epithelial
- closure of capillarity loops due to proliferation and swelling of endothelial cells +leukocyte infiltration
closure of capillary loops is something you see on LM in what renal disease?
PSGN
In IF of someone with PSGN, you will see granular deposits of _______ in the ____________
IgG and C3; mesangium and capillary walls
MPGN is characterized by: (3)
MPGN is a pattern under light microscopy NOT a diagnosis
- thickening of BM/ reduplicaiton of capillary BM
- mesangial proliferation
- infiltration of inflammatory cells
“Tram track” appearance
MPGN
What is the difference between type I and type II MPGN?
Type I: subendothelial deposits
Type II: dense material deposition along GBM (C3 GN = dense deposit disease only in kids)
A patients renal biopsy shows splitting of BM and a “tram track” appearance. What are some underlying diseases that they can have?
- lupus
- hepC
- cryoglubinemia
- endocarditis
- parasitic infection
- malignancy
Type I MPGN will have complement activation via the _____ pathway and Type II via the ________ pathway
Classical; alternative
What are some lab indications that would make you think of the diagnosis as dense deposit disease?
- normal C4 levels
- ↓ C3 elves due to C3 nephritic factor which stabilizes C3bBb convertase allowing for constant degradation of C3
- child
- MPGN like pattern (dense deposits of C3 in the GBM)
What is the typical presentation of someone with RPGN
Rapid decline in renal function with severe oliguria and pain. (One day normal, next day renal symptoms)
MEDICAL EMERGENCY
What would you see histologically (LM) in someone with RPGN?
Proliferative GN with prominent “crescent” formation in glomeruli w/ or w/o segmental necrosis
Discuss the different type of crescents seen in _________
RPGN;
New to old: cellular → fibrocellular → fibrous (cant treat fibrous because glomeruli already dead)
Type I RPGN has ______ staining on IF
Linear;
Anti GBM disease: good pastures or idiopathic
type 2 RPGN has _____ staining on IF
Granular;
Caused by immune complex diseases such as: SLE, post infectious, IgA, HSP
Type III has ______ pattern of staining on IF
NO STAINING;
Caused by pauci-immune GN which is a form of vasculitis with minimal evidence of HS upon IF staining: wegeners, microscopic PAN, Chung Strauss
Which diseases are associated with Type I RPGN?
Anti GBM disease: Goodpastures (linear)
What type of disease is associated with Type II RPGN?
Immune complex diseases such as:
- SLE
- post infectious
- IgA
- HSP
What disease are associated with Type 3 RPGN?
Pauci immune :
- Wegners
- Chung Strauss
- Microscopic PAN
SLE (lupus) is an autoimmune disorder of unknown etiology characterized by production of _________ and subsequent immune complex formation leading to chronic inflammation and tissue destruction
Autoantibodies
In lupus nephritis, there is an abnormal excess production of antibodies against “endogenous” nuclear antigens such as:
DsDNA, ANA (antinuclear antibody), Sm (anti-Smith), Ro, La
What MUST you be able to stain for and see in IF in order to diagnose lupus in a patient?
For all classes of lupus nephritis will have a full house (IgG, IgA, IgM, C1q, C3)
MUST HAVE C1Q
What is the difference between Class III lupus nephritis and Class IV lupus nephritis?
Class III: FOCAL (< 50% affected)
Class IV: DIFFUSE (> 50% affected)
What characterizes classs V lupus nephritis?
Class V is also called membranous lupus nephritis → SUBEPITHELIAL IMMUNE COMPLEX DEPOSITS with diffuse thinking of GBM (presents same as idiopathic membranous)
How is the disease activity of a patient with lupus monitored?
Measure:
- complement
- anti dsDNA antibodies
- ESR
- C-reactive protein
Quickly describe the classes of lupus (6) based on histology and EM:
Type I: minimal mesangial Type II: mesangial proliferative Type III: focal segmental proliferative Type IV: diffuse proliferative Type V: membranous Type VI: advanced sclerosing
