glomerulonephritis Flashcards
glomerulus
capillary network in the renal corpuscle that filters blood across capillary walls to Bowman’s capsule
nephritic syndrome
active glomerular inflammation with the presence of: RBCs and RBC casts protein in urine <3.5 HTN decline in kidney function
nephritic syndrome urinalysis findings
hematuria
acanthocytes
RBC casts
Proteinuria <3.5g/day
what are acanthocytes? why do they form?
dysmorphic RBC that looks like Mickey Mouse
form because of osmotic stress in the tubules
what does the presence of dysmorphic RBCs in urine mean?
indicate glomerular bleeding due to damage of the basement membrane
nephritic syndrome general pathophys
inflammatory response in glomeruli leads to basement membrane damage
=leakage of proteins and RBCs through porous membrane and decreased GFR
ANCA
anti-neutrophil cytoplasmic antibodies
what would make ANCA positive on blood work?
glomerulonephritis due to vasculitis
C-ANCA
autoantibody against proteinase 3
P-ANCA
autoantibody again myeloperoxidase
what is RPGN
rapidly progressive glomerulonephritis
- rapidly declining kidney function due to rapid destruction of glomeruli
- will rapidly progress to end stage renal disease
glomerular disease can either present as ____ or ____
nephritic or nephrotic syndrome
“itis” of the glomerulus
podocytes
cells that form the epithelial layer of Bowmans capsule, they have foot processes to help with filtration
most important initial test to diagnose glomerular disease
urinalysis
in the glomerulus blood enters via the ____ and exits via the ______
afferent arteriole
efferent arteriole
disease that shows crescent formation on biopsy
RPGN
what causes crescent formation
fibrin and plasma protein depositions cause Bowmans capsule to collapse and look like a crescent
gold standard to definitively diagnose glomerular disease
kidney biopsy
most common cause of acute glomerulonephritis
IgA nephropathy (Berger disease)
IgA nephropathy (Berger disease) commonly affects who
young males
IgA nephropathy (Berger disease) is triggered by
URI or GI infection (mucosal infections)
IgA nephropathy (Berger disease) pathophys
increased number of defective IgA antibodies are made and form immune complexes that are deposited in the glomerulus and lead to inflammation
post infectious GN is most common after___
10-14 days post group A Streptococcus infection
skin or pharyngeal strep
IgA nephropathy diagnosis
kidney biopsy showing IgA mesangial deposits on immunostaining
poststreptococcal diagnosis
kidney biopsy showing granular sub epithelial immune complex depositions of IgG, IgM, C3 along the GBM
“starry sky” appearance
Membranoproliferative GN (MPGN) usually occurs due to
SLE, HCV, HBV forming immune complexes that damage glomeruli
type 1 Membranoproliferative GN (MPGN) what is it and what does it show on kidney biopsy?
immunoglobulin mediated MPGN
sub endothelial IgG immune complexes on GBM
Type II Membranoproliferative GN (MPGN) what is it and what does it show on kidney biopsy?
Complement-mediated MPGN
intra-membranous C3 deposits on GBM
immune complex GN that presents as a mixed nephritic-nephrotic picture
MPGN, lupus nephritis too
mutation in gene encoding type IV collagen
Alport Syndrome
X-linked dominant autosomal recessive immune complex GN
alport syndrome
MPGN has ____ C3 serum levels and ____ C4
low
normal
3 main categories of RPGN
Immune Complex GN
Pauci-immune GN
Goodpasture’s (AntiGBM disease)
lupus nephritis pathophys
immune complexes deposit in glomeruli and cause damage
very dangerous and can lead to death in lupus pts
anti-GBM antibody disease (Goodpasture syndrome) pathophys
A type of RPGN that forms autoantibodies directly against collagen type IV in the GBM of the kidney and lung alveoli
presents with AGN and hemoptysis
goodpasture syndrome
IgA nephropathy/proteinuria treatment
ACE inhibitors +/- corticosteroids
lupus nephritis treatment
immunosuppression with cyclophosphamide
+/- corticosteroids
anti-GBM treatment (Goodpasture)
plasmapheresis
renal biopsy findings for Goodpasture
IgG deposits in GBM (also in lungs)
types of Pauci immune GN
Granulomatosis with polyangiitis
Microscopic Polyangiitis
Churg-Strauss
Pauci-immune GN features
no immune complexes deposited
+ ANCA antibodies
has a + P-ANCA
microscopic polyangiitis
P like puny, like microscopic
has a positive C-ANCA
granulomatosis with polyangiitis
(Wegener’s)
(C like cheesy granuloma)
what makes a nephritic/nephrotic picture?
hematuria and proteinuria >3.5 g / day
Alport has ___ C3 and ___ C4
normal normal
Anti-GBM has ___ C3 and ___ C4
normal
normal
lupus nephritis has ___ C3 and ___ C4
low
low
acute presentation, often have pulmonary renal syndrome
RPGN pts
