Nephritic Syndrome Flashcards
How is nephritic syndrome characterized?
Glomerular inflammation and bleeding
Clinical presenations of nephritic sndrome
Limited proteinuria
Oliguria and azotemia
Salt retention with periorbital edema and HTN
RBC casts and dysmorphic RBCs in urine
What is poststreptococcal glomerulonephritis (PSGN)?
Nephritic syndrome that arises after a group A-ß-hemolytic streptococcal infection of the skin (impetigo) or pharynx
What strains of GAS bacteria cause PSGN?
Nephritogenic strains that carry the M protein virulence factor
S/S of PSGN
Presentations begin 2-3 weeks after infection:
Hematuria
oliguria
HTN
Periorbital edema
What is seen on H&E stain of PSGN?
Hypercellular, inflamed glomeruli
How is PSGN mediated?
Immune complexe deposition
IF of PSGN
Granular IF
What is seen on EM of PSGN?
subepithelial humps
Tx for PSGN
Tx is supportive
Children rarely progress to renal failure (1%)
Some adults develop rapidly progressive glomerulonephritis (RPGN) (25%)
What is Rapidly Progressive Glomerulonephritis (RPGN)?
Nephritic syndrome that progresses to renal failure in weeks to months
What is the defining characteristic of RPGN?
Characterized by crescents in Bowman space of glomeruli on H&E stain
Crescents comprised of fibrin and mscrophages
What makes up crescents in RPGN?
Crescents comprised of fibrin and mscrophages
What is the etiology of a linear IF pattern in RPGN?
Goodpasture syndrome
Ab against collagen in glomerular and alveolar BM; Presents as hematuria and hemoptysis
Classically seen in young, adult males
What is the etiology of a granular IF pattern in RPGN?
Granular = immune complex deposition
PSGN (most common) or diffuse proliferative glomerulonephritis
Diffuse glomerulonephritis is due to diffuse Ag-Ab complex deposition, usually subendothelial; MC type of renal disease in SLE
What is the etiology of a negative IF pattern in RPGN?
Wegener granulomatosis, microscopic polyangitis, and Churg-Strauss syndrome
Wegener granulomatosis is associated with c-ANCA
Microscopic polyangitis and Churg-Strauss are associated with p-ANCA
Granulomatous inflammation, eosinophils and asthma distinguish Churg-Strauss from microscopic polyangitis
What is IgA nephropathy (Berger Dz)?
IgA immune complex deposition in mesangium of glomeruli
Most common nephropathy worldwide
May slowly progress to renal failure
Clinical presentations of IgA nephropathy
Presents during childhood as episodic gross or microscopic hematuria with RBC casts, usually following mucosal infections
IgA production is increased during infections
What is seen on the IF of IgA nephraopathy?
IgA immune complex deposition in the mesangium
What is alport syndrome?
Inherited defect in type IV collagen
Most commonly X-linked
Results in thinning and splitting of glomerular BM
S/S of alport syndrome
Isolated hematuria
Sensory hearing loss
Ocular disturbances
What is seen on the LM, EM and IF of Berger’s disease?
LM - Mesangial proliferation
EM - mesangial IC deposits
IF - IgA based IC deposits in mesangium
What condition can present as nephritic syndrome and nephrotic syndrome concurrently?
Diffuse proliferative glomerulonephritis
