Pathology of Glomerular Diseases Flashcards
4 clinical manifestations suggesting an underlying glomerular disease
- Proteinuria
- Hematuria
- Mixed pattern (proteinuria & hematuria)
- Acute kidney injury
Nephrotic syndrome signs (6)
- Heavy proteinuria
- Hypoalbuminemia
- Edema
- Hyperlipidemia
- Lipiduria
- Urine sediment: protein casts, fatty casts, liid droplets (maltese cross), oval fat bodies
RBCs can be seen but no RBC casts!
Nephrotic syndrome:
Primary disease is most prevalent in…
Secondary disease is most prevalent in…
Primary: mostly children
Secondary: mostly adults
Primary diseases that cause nephrotic syndrome (3)
- Minimal change disease
- Focal segmental glomerulosclerosis (FSGS)
- Membranous glomerulopathy
Mostly children
Secondary diseases that cause nephrotic syndrome (3)
- Diabetes mellitus
- Amyloidosis
- Pregnancy
Mostly adults
Proteinuria during pregnancy is usually a sign of …
maternal hypertension-pre-eclampsia
Signs of minimal change disease
Nephrotic syndrome!
- Selective proteinuria (albumin only)
- Preserved renal function
EM: diffuse effacement of foot processes
LM: Normal glomeruli
IF: negative
Typical presentation of minimal change disease
Abrupt onset of nephrotic syndrome in an otherwise healthy child.
Responds to short course of steroids
Great prognosis
One of the most common causes of nephrotic syndrome in adults
Focal segmental glomerulosclerosis (FSGS)
more common in african descent
Clinical manifestation of FSGS
- Nonselective proteinuria
- Mild or moderate hematuria
NO RBC CASTS! Nephrotic syndrome :)
What is the probable initiating event in primary FSGS?
Injury to podocytes
FSGS biopsy findings
- segmental and focal sclerosis of glomeruli
Collapsing variant of FSGS is associated with..
bad prognosis (HIV, severe manifestations)
FSGS response to steroids
poor - 50% develop ESRD within 10 years
Pathogenesis of membranous nephropathy
Basement membrane is attacked by antibodies (PLA2R)
Prognosis of membranous nephropathy
Not the worst - only 40% progress to renal failure over 2-20 years
Most common cancerous cause of membranous nephropathy
Hepatitis
Membranous nephropathy biopsy
- Diffuse thickening of glomerular capillary walls
- Spike formation
IM: IgG and C3 granular pattern
EM: sub-epithelial deposits, spikes
Frequent cause of secondary nephrotic syndrome in adults
Diabetes mellitus
Biopsy findings of secondary nephrotic syndrome due to diabetes mellitus
Kimmelstiel-Wilson lesions
Diffuse or nodular diabetic glomerulosclerosis
Arteriosclerosis of blood vessels
Proteinuria during pregnancy is usually a sign of…
maternal pre-eclampsia (hypertension and proteinuria due to endothelial dysfunction).
BIOPSY NOT REQUIRED
3 causes of primary glomerulonephritis (nephritic syndrome)
- Acute post-infectious GN
- IgA nephropathy
- Membrano-proliferative GN
Acute post-infectious glomerulonephritis (nephritic syndrome) often presents in children (and sometimes adults) some weeks after…
beta-hemolytic group A streptococcal infection of upper respiratory tract or skin
Common infections (esp. in adults) that lead to acute post-infectious glomerulonephritis
Staphylococcus, pneumococcus, viruses, pneumonia, endocarditis, skin infections
Characteristic signs of acute post-infectious glomerulonephritis (6)
Rusty urine (tea-coloured, coca-cola)
Edema
Hypertension
RBC casts
Mild to moderate proteinuria
Hypercellularity (neutrophils)
Crescents in post-infectious glomerulonephritis indicate…
worse prognosis
Acute post-streptococcal GN (nephritic) presents with.. on immunosfluorescence
Large coarse granular deposits or C3 and IgG (humps)
Prognosis for acute post-infectious GN
Usually good prognosis unless necrosis and crescents
Very rare ESRD
Most common biopsy features of IgA nephropathy (nephritic syndrome)
Mesangial cell proliferation (histology)
Mesangial deposits of IgA (IF)
What is henoch-schonlein purpura?
A systemic form of IgA nephropathy with vasculitis (nephritic syndrome)
Presentation of henoch-schonlein purpura
Gross hematuria, GI symptoms (tummy aches, vomiting, diarrhea) and rashes on lower extremities
Rapidly progressive glomerulonephritis (nephritic syndrome)
RPGN results in rapid loss of renal function in a few days or weeks, typically in the setting of nephritic syndrome
Characteristic histologic finding associated with RPGN
Presence of crescents
Is RPGN dangerous?
Yes! It is a medical emergency!If untreated, leads to death from renal failure
Difference between acute and chronic crescentic GN
Acute: cellular crescent
Chronic: fibrous crescent
Most common glomerular disease in the world
IgA nephropathy
Acute pyelonephritis
Acute suppurative inflammation of the kidney and renal pelvis caused by bacterial infection (E coli).
Characterized by fever, chills, pain, dysuria, urgency.
2 types of acute pyelonephritis (how the bacteria reach the kidney)
Ascending: From lower UTI
Hematogenous: sepsis, infective endocardidtis
Acute pyelonephritis is usually..
a) unilateral
b) bilateral
a) unilateral
How are glomeruli affected in acute pyelonephritis?
Glomeruli are NOT affected!!!
Papillary necrosis
Special and severe form of pyelonephritis (ischemic necrosis of pyramids and papilla, most often seen in the context of diabetes, obstruction or analgesic abuse)
Acute Tubulointerstitial Nephritis
Adverse drug reaction to antibiotics and analgesics (penicillin, diuretics, NSAIDs). Abnormal immune reaction (hypersensitivity).
Main indicator of ATN
Red granules (eosinophils)
Most common cause of acute kidney injury
Acute tubular injury (i.e. acute tubular necrosis)
Cause of acute tubular injury/necrosis
Ischemic or toxic injury to tubules
Chronic kidney injury is a broad term that describes the final common pathway of…
progressive nephron loss from any type of kidney disease
