Warren- Glomerular Disease Flashcards
What is primary COD in 4-10% of PCKD pts?
Intracranial berry aneurysm
What is the inheritance pattern for childhood PKD?
Autosomal recessive!
What is seen both grossly in childhood PKD?
gross: ENLARGED SMOOTH externally–cut section shows SMALL CYSTS in CORTEX and MEDULLA
Does childhood PCKD occur unilaterally or bilaterally?
Bilaterally
Liver cysts and bile duct proliferation is seen in almost ALL pts w/ what disease?
childhood PCKD
If children w/ PCKD survive infancy, what may you observe?
congenital hepatic fibrosis–periportal fibrosis and proliferation of bile ductules
What is medullary sponge kidney? Who does it commonly affect?
Cystic dilations of collecting ducts in the medulla>
HEMATURIA, infection, stones>
MAINTAIN NORMAL kidney fxn
ADULTS
What will you observe grossly in medullary sponge kidney?
Dilated papillary ducts in the medulla
What is nephronophthisis?
onset in CHILDHOOD>
Cysts in the medulla>
cortical TUBULAR ATROPHY and interstitial fibrosis>
child presents w/ polyuria and polydipsia d/t tubular defect
What is acquired cystic disease and why can it be bad?
Usually asymptomatic but 7% of dialysis pts will develop RENAL CELL CARCINOMA w/in the cysts (after about 10 yrs)
What is the clinical significance of finding a single simple cyst in a kidney? Where are they usually located and what do they look like?
Usually no clinical significance but you have to differentiate it from a tumor
1-5 cm filled with clear fluid, single layer of cuboidal or flattened epithelium line the cysts
What is glomerulonephrITIS?
IMMUNE MEDIATED DISEASE
What are examples of primary glomerulonephritis?
Minimal change
membranous
What are examples of secondary glomerulonephritis?
Diabetes mellitus
SLE
Vasculitis
AMyloidosis
What are the three histological patterns seen with glomerular injury?
- HYPERCELLULARITY
- BASEMENT MEMBRANE THICKENING (BM material or deposited material Ag-Ab)
- HYALINIZATION AND SCLEROSIS
What causes the formation of crescents?
Proliferating epithelial parietal cells next to infiltrating WBCs
What tools are used to evaluate renal disease?
H and E
PAS- magenta and pink
Trichrome- blue green
silver- black
IF
EM
What type of immune response occurs in anti-GBM Glomerulonephritis?
IN SITU COMPLEX CEPOSITION
Ab are directed against normal components of the GBM
What is indicative of anti-GBM glomerulonephritis on IF?
Homogenous, diffuse LINEAR pattern
How does anti-GBM glomerulonephritis relate to Good pasture’s syndrome?
Ab can cross react w/ other basement membranes like those in the alveoli> hemoptysis
The Ag associated with anti-GBM Glomerulonephritis and Good Pasture’s syndrome is part of what component of the BM?
NC1 domain of the alpha 3 chain of Type IV collagen
Heymann Nephritis is associated w/ what immune mediated response?
IN SITU COMPLEX DEPOSITION
What Ag is Heymann Nephritis associated with?
M type phospholipase A2 receptor
What is commonly seen on IF and EF in a pt with Heymann nephritis?
IF: granular and interrupted pattern
EM: electron dense deposits
Ab bind ag>
activates complement>
complexes shed and aggregate
What are “planted antigens”?
IN SITU complex deposition
Ags from NON-GLOMERULAR ORIGIN localize in the kidney>
Abs form against them
(DNA, bacterial products, aggregated Igs)
What is circulating Immune Complex Nephritis? What type of injury is this?
Circulating Ag-Ab complexes get trapped in the glomerulus (usually SUBENDOTHELIAL) and cause glomerular injury.
Type III hypersensitivity rxn
What is hte source of Ags associated with circulating immune complex nephritis?
Endogenous (SLE)
Exogenous (streptococci)
Once GFR is reduced to 30-50% of normal progression to end stage renal failure proceeds at a steady rate. What histological findings are associated with the progression of glomerular disease?
Focal segmental glomerulosclerosis
Tubulointerstitial fibrosis
What is FSGS?
Loss of function of nephron>
adaptive changes in the glomerulus>
hypertrophy of gloms to make up for rest of nephron>
increased flow/filtration/transcapillary pressure in individual glomeruli>
SEGMENTAL SCLEROSIS in those glomeruli over time
What is the one thing that can delay or slow down FSGS?
ACE inhibitors
What is tubulointerstitial fibrosis?
Glomerularnephritides>
ISCHEMIC TUBULES downstream from sclerotic glomeruli
PROTEINURIA directly toxic to downstream tubular cells
Increased acute and chronic inflammation> SCARRING
What are the key features of a nephritic syndrome?
INFLAMMATORY AND PROLIFERATIVE
hematuria and red cell casts
some proteinuria
azotemia
HTN
What are key features of nephrotic syndrome?
PROTEINURIA > 3.5 G/24 HRS>
hypoalbumininemia>
edema
Hyperlipidemia>
hyperlipiduria (fat in urine)
What is a common finding associated w/ nephrotic glomerulonephritis?
damage to visceral epithelial cells (PODOCYTES)
What is Acute poststreptococcal glomerulonephritis? What population is it common in?
Group A beta hemolytic streptococci are nephritogenic>
1-4 wks post strep pharyngeal or skin infection>
Acute poststreptococal glomerulonephritis
KIDS
If a child comes in who you think has acute poststreptococcal glomerulonephritis, how do you assess them?
Usually don’t need a kidney biopsy.
C3 levels LOW
Serum + for:
Antistreptolysin O
antiDNase B
What is seen histologically wtih APS GN?
Large hypercellular glomeruli (proliferation of endo/mesang cells and infiltration of WBC)
What is seen on IF AND EM of APS GN?
IF: VERY GRANULAR glomeruli
EM: SUBEPITHELIAL HUMPS! (CAMEL)
If a child presents with SMOKY URINE, red cell casts, mild proteinuria, PERIORBITAL EDEMA, and mild HTN what might they have? How does this differ from an adult presentation?
APS GN > 95% children recover
Adults often have more atypical presentation–only 60% recover
What is rapidly progressive (cresentic) GN?
SEVERE injury to the glomerulus
> 50% have crescents
*Crescents are proliferations of parietal epithelial cells of bowmans capsule + inflammaotry cells
What are the three classifications of RPGN?
I: anti-GBM GN–> linear deposits
II: immune complex mediated–> lumpy- bumpy (PSGN, SLE, IgA)
III: Pauci- immune type–>can’t see deposits, but most pts have p or c-ANDA in peripheral blood
How does RPGN present histologically?
Large pale kidneys w/ PETECHIAE
CRESCENT FORMATION >50% of glomeruli
RUPTURES IN GBM
What is the clinical presentation for RPGN?
Typical Nephritic (hemturia + red cell casts, mod proteinuria, HTN, edema)
BUT it progresses over several weeks w/ SEVERE OLIGURIA
What pathophysiology is associated w/ nephrotic syndrome?
Increased permeability of GBM to proteins–> MASSIVE PROTEINURIA> hypoalbuminemia–> decreased osmotic pressure>
edema
Increased liver synthesis of LIPOPROTEINS
Increased risk for INFECTIONS d/t loss of Ig and complement
HYPERCOAGUABLE STATE d/t loss of anticoagulants
What is the primary cuase of nephrotic syndrome in children?
MCD
What is the primary cuase of nephrotic syndrome in adults?
FSGS
What percent of membranous GN are idiopathic and what are common secondary causes?
85%
Drugs: NSAIDS
Malignancy
SLE
Infections: HBV, HCV
What is the pathogenesis of membranous GN?
CHronic Ag-Ab mediated disease–>
complement mediated damage to GBM
What is microscopic evidence of membranous GN?
Diffuse thickening of capillary wall CHEERIOS
SPIKES (basement membrane material laid down between the deposits)
How do subepithelial deposits occur in membranous GN?
Subepithelial deposits (IgG and C3)>
Spikes on basement membrane>
thickened GBM w/ lucent defects (deposits are resorbed)>
effacement of foot processes
What is the typical course of membranous GN?
chronic proteinuria with SLOW deterioration
What is the MCC of nephrotic syndrome in children 2-6 years? How is it treated?
Minimal Change disease
CORTICOSTEROIDs
What is MCD associated wtih?
Atopy (eczema)
URI
Immunization
HOdgkin lymphoma
What is the pathogenesis of MCD?
Visceral epithelial cell injury—>
podocytes become detached–>
appear flattened out
What disease has NORMAL GLOMERULI w/ EM showing diffuse EFFACEMENT OF FOOT PROCESSES OF visceral epithelial cells and NO deposits?
MCD
What is the clinical course of MCD? Can it recur? Can the damaged be reversed by steroid therapy?
MASSIVE PROTEINURIA that is mostly albumin
No renal failure, no HTN
YES
YES
What is FSGS?
Sclerosis of SOME gloms (FOCAL) in a PORTION of the glomerulus (SEGMENTAL)
What is FSGS associated with?
HIV
heroine
sickle cell
morbid obesity
What is the pathogenesis of FSGS?
Genetic abnormalities of proteins which localize to the slit diaphragm (nephrin and podocin)
What might you see on an IF of FSGS? Microscopically?
Mesangial deposits of IgM and C3
Foam cell
What is hte clinical course in FSGS?
Nephrotic syndrome, HTN, reduced GFR>
poor response to corticosteroids>
at least 50% have ESRD in 10 yrs
*often recurs quickly w/ transplant
What may worsen the prognosis of FSGS?
HIV nephropathy
What is seen on EM of HIV nephropathy?
TUBULORETICULAR INCLUSIONS in endothelial cells (also seen w/ lupus)
What is membroproliferative GN characterized by?
Proliferation of glomerular cells and leukocyte infiltration–>
damaged GBM
May also present with a mild nephrotic syndrome
What is MPGN associated with?
SLE
Hep B adn C
Endocarditis
*Partial lipodystrophy
Alpha-1 antitrypsin def
Malignancy
What is seen microscopically in type II and II MPGN?
Large hypercellular glomeruli w/ lobular arcthitecture
thickened GBM (train track/double contour)
What is unique to type I MPGN in terms of IF?
IF: C3 and C1q
What is the pathogenesis of type I MPGN?
Immune comlex disease–> activation of classic and alternative comlement pathways>
subendothelial deposits
2/3 of cases of MPGN
What is type II MPGN known as?
DENSE DEPOSIT DISEASE–> lamina densa of GBM is ribbon like
usually d/t excessive acativation of alternative complement pathway
What is the clinical course for MPGN?
50% develop chronic renal failure in 10 yrs
steroids not helpful
recurs after transplant (esp type II)
What is the MC type of glomerulonephritis world wide?
IgA Nephropathy Berger disease?
What might you see in a pt with IgA nephropathy?
Recurrent hematuria
proteinuria (can be in nephrotic range)
What is IgA nephropathy associated with?
gluten enteropathy
liver disease
What does IgA nephropathy have overlapping features with?
Henoch Schonlein purpura
What is the pathogenesis of IgA nephropathy?
IgA is IG of secretions and it is normally low in the serum
Increase in polymeric IgA in the serum>
aberrantly glycoslyated>
IgA IC deposit or are formed in MESANGIUM
What is seen on IF and EM of IgA nephropathy?
IF: mesangial deposition of IgA
EM: mesangial deposits
A pt presents w/ hematuria following a URI, GI infection or UTI. The hematuria lasts a few days, disappears then recurs. What does this pt have?
IgA nephropathy
What is herediatry nephritis?
Herediatry diseases associated with glomerular injury
alport syndrome
thin membrane disease
What characterizes alport syndrome?
nephritis
nerve deafness
eye disorders
Who is most commonly affected w/ alport syndrome? WHy?
Males
Inheritance is usually X-linked dominant
can be autosomal recessive or autosomal dominant
What is commonly seen on an EM of alport syndrome?
Irregular thick and thin GBM with SPLITTING of the lamina densa
What is the pathogenesis of alport syndrome?
DEFECTIVE GBM synthesis
mut in gene encoding aklpha chain of type IV collagen
What is the clinical course of alport syndrome?
Hematuria at 5-20 yrs (may also have proteinuria)>
renal failure by age 20-50
What is thin membrane disease?
Common disease that presents w/ hematuria
Diffuse thinning of GBM d/t abnormal genes encoding collagen chains
Usually good prognosis
What is chronic glomerulonephritis? How does it appear gross and micro?
End result of many types of GN
Small, diffusely granular kidneys
globally hylanized glomeruli
What two diseases most commonly progress to chronic GN?
RPGN (cresenteric)
FGS
If an SLEL pt has kidney involvement, how does it appear on an IF and EM evaluation?
IF- fullhouse, stains everything
EM- wire loop lesion, thickening of capillary wall by subendothelial deposits
A child that is 5 years old presents w/ abdominal pain, vomitting and purpuric skin lesions on his arms, legs and buttocks. He also has some hematuria. What might this pt have?
Henoch schonlein purpura
What causes HS purpura?
IgA deposited in the mesangium
child 3-8
What is diabetic nephroaphty?
Proteinuria occurs in 50% of type I and II diabetics 12-22 yrs after dx of DM
What do you see microscopically w/ diabetic nephropathy?
- capillary basement membrane thickening
- diffuse mesangial sclerosis
- **nodular glomerulosclerosis–hyaline masses at the periphery of the glomerulus (vascular pole of glomerulus is often thickened and hylanized)
What is the pathogenesis of diabetic nephroapthy?
- metabolic defect- increase in type IV collagen, NE glycosylation of proteins–> thickened GBM and increased mesangial matrix
- Hemodynamic effect- increased GFR and glomerular hypertrophy> increased filtration> glomerulosclerosis