renal review Flashcards
what are the typically proteinuria values of nephrotic and nephritic syndromes?
nephrotic > 3.5g/24h
nephritic < 3.5g/24h
do you have a problem making urine in nephrotic or nephritic syndromes?
nephritic
No problem in nephrotic, typically have an excess
what primary glomerular lesions lead to nephrotic syndrome?
MCD FSGS membranous glomerulopathy membranoproliferative glomerulonephritis (often nephritic) IgA nephropathy (often nephritic)
what systemic diseases can lead to nephrotic syndrome?
diabetes mellitus
SLE
amyloidosis
how do we diagnose MCD (what do we see on LM, EM, and IF)?
LM: normal glomeruli
IF: no staining, looks normal
EM: diffuse effacement of foot processes
what are the clinical features of FSGS?
proteinuria: nephrotic or non-nephrotic range
hematuria, hypertension
patients with FSGS usually do not respond well to what type of medication?
steroids
is FSGS rapidly or slowly progressing?
slowly
what population is most susceptible to FSGS?
black african american
how many of the glomeruli are damaged in FSGS?
<50%
what is the worst variant of FSGS?
collapsing glomerulopathy
idiopathic or HIV associated
how do we tell the difference between MCD and FSGS on LM?
you can see segmental sclerosis in FSGS
what is the hallmark of membranous glomerulopathy histologically?
GBM spikes on silver stain (jones)
what do you see on IF in membranous glomerulopathy?
granular IgG
C3 on capillary wall
what do you see on EM in membranous glomerulopathy?
subepithelial deposits regularly distributed along GBM
what is the typical presentation of glomerulonephritis (MPGN)?
proteinuria - typicaly nephrotic, but may be mild
hematuria, may be accompanied by nephritic syndrome
hypocomplementemia (low serum C3)
proliferation and thickening of capillary wall
most common form of MPGN
type 1 - lupus, hep C
what causes type II MPGN?
c3 nephritic factor
what is pathological about MPGN Type I?
hypercellular glomeruli: increased mesangial and infiltrating mononuclear cells in global distribution
thick-walled capillary loops: double contour or “tram track”
crescents (Rare)
what do we see on IF of MPGN type I?
granular C3 along capillary walls at the periphery of lobule (central sparing) often with IgG and IgM
what do we see on EM of MPGN type I?
immune deposits in subendothelial and mesangial locations
what two diseases are common etiologies of MPGN type I?
HCV and lupus
what is MPGN type II?
dense deposit disease
autoimmune disease with autoantibodies (C3 nephritic factor) directed at C3bBb
what are the clinical symptoms of acute nephritic syndrome?
hematuria +/- RBC casts
hypertension
azotemia, oliguria (usually transient)
edema, proteinuria variable (<3g/24h)
what are the etiologies of acute nephritic syndrome?
typically immune mediated
post-infection GN (post-strep)
primary glomerular disease (IgA nephropathy, MPGN - lupus)
what are the clinical features of acute post-infectious glomerulonephritis?
abrupt onset oliguria, elevated BUN and creatinine
anti-streptolyin O (ASO) in serology (for post-strep)
decreased serum C3 (this is how they monitor kids)
what do you see on histological slides for acute post-infectious glomerulonephritis?
diffuse proliferative glomerulonephritis (TONS of neutrophils)
hypercellular: proliferation of mesangial and other cells
exudative: neutrophils and mononuclear cells present
what do you see in IF of acute post-infectious glomerulonephritis?
coarsely granular deposits of IgG and C3
what do you see in EM of acute post-infectious glomerulonephritis?
subepithelial humps
what is the second most common cause of kidney failure in the world?
IgA nephropathy
what is pathological in IgA nephropathy?
they make IgA immunoglobulin incorrectly (only IgA1, not IgA2)
can look like a lot of diff things on LM, but if they diagnose they use IF: IgA strong staining within mesangium
what do you see in IF for IgA nephropathy?
strong IgA staining within mesangium
what is the clinical presentation of rapidly progressive GN?
acute nephritis with oliguria, RBC casts, hypertension
rapid loss of renal function (acute renal failure)
**really rapid creatinine increase and almost all associated with crescents.
what are the three types of glomerular injury that contribute to the pathogenesis of rapidly progressive GN?
type I: anti-glomerular antibody (anti-GBM)*
type II: immune complex
type III: anti-neutrophil cytoplasmic antibodies (ANCA)*
what causes the formation of a crescent?
proliferation of parietal epithelial cells forming layer >2 cells thick, involving >50% circumference
what syndrome often leads to anti-GBM disease?
goodpasture syndrome (if lung hemorrhage also present)
what do you see on IF for anti-GBM disease?
linear IgG along capillary wall (nothing else looks like this in kidney disease!)
what antibodies are found in Wegener Granulomatosis?
ANCA (know that this exhibits as little to no staining on IF)
how does Wegener Granulomatosis appear on IF?
it’s pauci-immune (not much staining for ANCA pathologies)
you see some crescent formation otherwise
do you see crescents in Wegener Granulomatosis?
yes
what antibodies are present in SLE?
all he wants us to know is ANA present in essentially all patients
when you see a patient presenting with clots and multiple miscarriages what pathology would you be suspicious of?
SLE
*due to anti-phospholipid antibodies
what type of stain do you typically see for SLE?
FULL HOUSE STAIN
what are the three renal syndromes attributable to diabetic neuropathy?
microalbuminuria or non-nephrotic proteinuria
nephrotic proteinuria
chronic renal failure
what is kimmelstiel-Wilson disease?
nodular glomerulosclerosis due to diabetic neuropathy
what do you see within the arterioles of patients with diabetic neuropathy?
hyaline deposits
what do you see on EM of diabetic neuropathy?
thickened GBM with no deposits and mesangial expansion
amyloid on congo red stain presents with what?
apple-green birefringence (due to characteristic ß-pleated sheets
how does amyloid appear on EM?
non-branching fibrils
what is characteristic of myeloma cast nephropaty (in staining)?
fractured casts
cryoglobulinemia is typically associated with what disease?
HCV
what are the causes of acute tubular necrosis?
ischemic: shock
antibiotics
radio-contrast agents
NSAID nephropathy is the cause of what type of renal disease?
tubulointerstitial disease
what is allergic tubulointerstitial nephritis?
hypersensitivity reaction to drug especially antibiotics
what is a hallmark of allergic tubulointerstitial nephritis?
fever, rash, peripheral blood eosinophilia
acute renal failure
urine contains RBC, WBC (especially eosinophils)
typically appears about 2 weeks after drug started
what do we see on IF for myeloma cast nephropathy?
exclusively one light chain isotype (typically kappa light chain) because of monoclonal proliferation
what is characteristic about the group of disorders categorized as thrombotic microangiopathies?
microthrombosis of arterioles and capillaries
what is the most common etiology of thrombotic microangiopathy?
hemolytic-uremic syndrome
hemolytic-uremic syndrome typically follows what illness?
respiratory or GI distress (very common after E.Coli infection)
clinically often seen after person eats hamburger gets infected with O157:H7
what happens to the kidneys after a patient takes immunosuppressants over time?
damage to the kidney
tacrolimus, cyclosporine used in allograft rejection prevention
what causes hyperacute rejection?
preformed antibodies
minutes to hours after vascular anastamosis
what is the clinical renal picture of acute cellular rejection?
sudden azotemia (elevated creatinine, BUN)
what is the renal pathology seen in acute cellular rejection?
interstitial inflammation: lymphocytes
what primary diseases are most likely to recur?
MPGN
anit-GBM disease
IgA nephropathy
FSGS
what are the causes of urinary tract obstruction?
BPH
tumors
calculi (stones)
congenital abnormalities (typically seen in children)
what is hydronephrosis?
dilation of renal pelvis, calcyes, and ureter due to obstruction
when urine can’t get out (dilation of renal pelvis, calyces, and ureter due to obstruction)
what forms the largest type of stone (urolithiasis)?
struvite (magnesium ammonium phosphate)
when do struvite stones form?
after infection with a urea-splitting bacteria (typically Proteus)
stones of what type result in staghorn calculi?
struvite
most common stone
calcium (oxalate and phosphate)
what are the two types of polycystic kidney disease?
AD PKD
AR PKD
what is unique about ADPKD?
cysts everywhere (berry aneurysms in circle of willis, hepatic cysts, cysts in pancreas lung and spleen, kidneys enlarged bilaterally, slowly overtime this replaces the entire kidney)
does ADPKD cause slow or rapid progression to renal failure?
slow
what is the molecular pathogenesis of ADPKD?
they make polycystin-1 inappropriately
when does ARPKD usually present?
typically in childhood
30% die as neonates due to lung hypoplasia
what macropathology do you see in patients with ARPKD (renal related)?
enlarged kidneys with smooth surface (cysts are small and enlongated perpendicular to surface)
what is the hallmark of oncocytoma?
grossly tan or brown encapsulated stellate scar and large eosinophils
**benign, but can still grow large enough that you need to remove the entire kidney
what is the most common cause of kidney cancer?
renal cell carcinoma
is renal cell carcinoma familial or sporadic?
sporadic
where do you typically find clear cell carcinoma (what pole of the kidney)?
upper pole
what mutation causes wilm’s tumor?
WT1
is wilm’s tumor encapsulated or non-encapsulated?
encapsulated
what is the most common primary renal tumor in children?
wilm’s tumor
What is the normal BUN:creatinine ratio?
15
Patients exposed to ethylene glycol show development of what in the urine
oxalate crystals
What is one of the highest yield findings of acute (allergic) interstitial nephritis?
Eosinophils in urine
IF- shows coarsely granular deposits of IgG and C3, EM- shows subepithelial “humps.” What do u think they have?
acute post-infectious glomerulonephritis
SLE kidney disease *buzzwords?
- full house stain
- mesangial deposits
- subendothelial deposits
_________ pattern most common for hep C and lupus
MPGN…..
specifically MPGN type 1 for hep C
cracked casts, dif colors in the cast, cellular reaction =
myeloma cast nephropathy
pathogenesis of malignant nephrosclerosis
renal failure, death if not treated immediately
thrombotic microangiopathy is a group of disorders characterized by
microthrombosis of arterioles and capillaries, which is caused by microangiopathic hemolytic anemia test q
hemolytic-uremic syndrome can cause ________________, which can often lead to acute renal failure & death in 1/2 adults who get this
thrombotic microangiopathy
Hemolytic-Uremic syndrome clinical finidings
acute renal failure,
thrombocytopenia,
hemolytic anemia
