Flashcards in Renal Pathology 1-Nephritic syndrome Deck (21):
Post infectious glomerulonephritis
Typical clinical presentation
Typical clinical presentation:
Children: acute nephritic syndrome
(hematuria, edema, hypertension, renal failure)
Adult: acute nephritic syndrome may be less common
Typically children 6-10yrs
rarer in adults
sporadic or endemic
-1-4 weeks after recovery from infection:
Group A B-hemolytic strep
Other: pneumococcal, staphylococcal, viral
What is the pathogenesis of post-infectious glomerulonephritis?
1. immune complexes form in the circulation (antigen+IgG)
2. deposition of immune complexes in the *capillary wall activates complement (C5a) which attracts neutrophils
3. Neutrophils mediate damage with *endocapillary proliferation and structural damage (swiss cheese) with hematuria
4. immune complexes also formed in situ leading to *subepithelial deposits "humps" which are unique to postinfectious glomerulonephritis and therefore diagnostically useful
What will you see in histology/pathology in post infectious glomerulonephritis?
1. endocapillary proliferation (hypercellular tuft?, capillaries occluded)
2. neutrophilic infiltrate
3. immune complex deposits by immunofluorescence and electron microscopy
What lab tests results will there be with postinfectious glomerulonephritis?
-hematuria, mild proteinuria
-ASO titer increase
What is the prognosis and treatment for a patient with postinfectious glomerulonephritis?
1. Children=total recovery in >95%
2. Adults=slow progression to CHRONIC glomerulonephritis
3. 15-50% of adults develop end stage kidney disease
4. A small subset of children and adults may develop very severe acute illness with gross hematuria and rapidly progress to renal failure
Is a kidney biopsy necessary in post infectious glomerulonephritis?
only if course is atypical
What is the typical presentation of IgA nephropathy (aka Berger disease)
1. RECURRENT gross and microscopic hematuria
2. episodes of gross hematuria within 1-2 days of a nonspecific upper respiratory infection (also GI or GU tract)
3. Painless hematuria
4. Hematuria for days, recurrent every few months
What is the epidemiology and etiology of IgA nephropathy AKA berger disease?
1. most common glomerular disease worldwide *
2. children and young adults
1. Mucosal infection leads to production of IgA and formation of IgA containing immune complexes which deposit in the mesangium
a. increased IgA synthesis (respiratory or GI exposure to viruses, bacteria, food products)
b. genetic or acquired abnormalities of immune regulation (celiac disease)
c. abnormalities of clearance of IgA
d. antibodies against abnormally glycosylated IgA
5. activation of the complement (alternative pathway)
What is the difference in the immunofluorescence of post infectious glomerulonephritis and IgA nephropathy?
In IgA nephropathy the blotches are bigger and sit preferentially in the mesangium
Where is there the least IgA nephropathy?
africa and middle east
What is IgA nephropathy with extra-renal symptoms, which is normally seen in adults where they get small vessel vasculitis and skin purpura and gastrointestinal problems?
Henoch-Schoenlein purpura (HSP)
What do the immune complexes in IgA nephropathy contain? Does this affect the level of complement?
IgA + complement
IgA is a poor activator of the complement system
-complement involvement is via the alternative pathway rather than classic
-complement levels are replenished by the live and usually do not decrease
What does the histology for IgA nephropathy look like?
-IgA-containing immune complexes in the mesangium=diagnostic
-electron dense deposits by electron microscopy
What are the lab test results of a patient with IgA nephropathy?
hematuria, mild proteinuria
complement levels normal
What is the prognosis and treatment of IgA nephropathy?
1. dependent on glomerular pathology
-many relatively indolent/prolonged, ultimately renal failure
-small portion aggressive course
Is a kidney biopsy needed in IgA nephropathy?
for more specific diagnosis
What is hereditary nephritis-AKA alport syndrome?
A group of hereditary glomerular disease
-mutations in glomerular basement membrane proteins
-error in synthesis of collagen type 4, the major component of the glomerular basement membrane
-Type 4 collagen is also in other tissues-lens, cochlea
How is hereditary nephritis AKA alports syndrome genetically linked? What is the triad found in this disease?
2. nerve deafness
3. various eye disorders, early cataracts
What is the typical clinical presentation/epidemiology/etiology of hereditary nephritis aka alports syndrome?
1. hearing loss and ocular abnormalities
2. isolated hematuria
1. 5-20 years at presentation
2. 20-50 years with overt renal failure
-X linked inheritance most common
-+ family history
Females-carries with rare disease (x-chromosome inactivation)
What is the histological presentation of hereditary nephritis?
1. paraffin sections: normal, nondiagnostic
2. immunofluorescence: negative-NO immune complexes
lamina densa splitting and lamination: basket weave