Nephrotic & Nephritic Syndromes

Question 1

Which part of the nephron is affected in nephrotic and nephritic syndromes?

Answer 1

Glomerulus

Question 2

Define nephrotic syndrome

Answer 2

Syndrome characterised by proteinuria >3g/24h, hypoalbuminaemia, and oedema. There will likely be hyperlipidaemia.

Question 3

State the three primary causes of nephrotic syndrome

Answer 3

Minimal change disease, membranous glomerular disease, focal segmental glomerulosclerosis (GSGS)

Question 4

Define nephritic syndrome

Answer 4

Syndrome characterised by PHAROH: Proteinuria (less than nephrotic syndrome), Haematuria, Azotaemia (high urea and creatinine), Red cell casts in urine, Oliguria, and Hypertension

Question 5

State at least three causes of nephritic syndrome

Answer 5

Acute post-streptococcal glomerulonephritis, Berger disease (IgA nephropathy), rapidly progressive (crescentic) glomerulonephritis, hereditary nephritis (Alport’s syndrome), thin basement membrane disease(benign familial haematuria)

Question 6

Describe the epidemiology of minimal change disease

Answer 6

75% of cases in children, second peak in elderly

Question 7

Describe the epidemiology of focal segmental glomerulosclerosis (FSGS)

Answer 7

Most common in adults of Afro-Caribbean descent

Question 8

Describe the signs of minimal change disease under light microscopy

Answer 8

No changes

Question 9

Describe the signs of minimal change disease under electron microscopy

Answer 9

Loss of podocyte foot processes

Question 10

Describe the signs of membranous glomerular disease under light microscopy

Answer 10

Diffuse glomerular basement membrane thickening

Question 11

Describe the signs of membranous glomerular disease under electron microscopy

Answer 11

Loss of podocyte foot processes, subepithelial deposits giving a spikey appearance

Question 12

Describe the signs of focal segmental glomerulosclerosis under light microscopy

Answer 12

Focal and segmental glomerular consolidation and scarring, hyalinosis

Question 13

Describe the signs of focal segmental glomerulosclerosis under electron microscopy

Answer 13

Loss of podocyte foot processes

Question 14

Describe the signs of minimal change disease under immunofluorescence

Answer 14

No immune deposits

Question 15

Describe the signs of membranous glomerular disease under immunofluorescence

Answer 15

Ig and complement in granular deposits along entire glomerular basement membrane

Question 16

Describe the signs of FSGS under immunofluorescence

Answer 16

Ig and complement in scarred areas

Question 17

State the underlying causes of membranous glomerular disease

Answer 17

Idiopathic (primary), SLE, infection, drugs, malignancy

Question 18

State the underlying causes of FSGS

Answer 18

Idiopathic (primary), obesity, HIV nephropathy

Question 19

State two secondary causes of nephrotic syndrome

Answer 19

Diabetes mellitus, amyloidosis

Question 20

Describe the histological appearance of diabetic nephropathy

Answer 20

Diffuse glomerular basement membrane thickening, Kimmelstiel Wilson nodules (mesangial matrix nodules)

Question 21

Describe the histological appearance of renal amyloidosis

Answer 21

Apple green birefringence with Congo red stain

Question 22

Describe acute-post infectious glomerulonephritis

Answer 22

Occurs 1-3 weeks after streptococcal throat infection or impetigo. Immune complex deposition leads to glomerular damage, haematuria, proteinuria, oedema, and hypertension

Question 23

Describe the features of acute post-infectious glomerulonephritis on light microscopy

Answer 23

Increased cellularity of glomeruli

Question 24

Describe the features of acute post-infectious glomerulonephritis on electron microscopy

Answer 24

Subendothelial humps

Question 25

Describe the features of acute post-infectious glomerulonephritis on fluorescent microscopy

Answer 25

Granular deposits of IgG and C3 in the glomerular basement membrane

Question 26

Describe IgA nephropathy (Berger disease)

Answer 26

Deposition of IgA immune complexes in the glomeruli 1-2 days after an UTRI, causing frank haematuria

Question 27

Describe the features of IgA nephropathy on fluorescent microscopy

Answer 27

Granular deposition of IgA and complement in mesangium

Question 28

State the three types of rapidly progressive glomerulonephritis

Answer 28

Type 1: anti-glomerular basement membrane antibody Type 2: immune complex Type 3: pauci-immune/ ANCA-associated

Question 29

How is rapidly progressive glomerulonephritis characterised?

Answer 29

Presence of crescents in glomeruli

Question 30

State the causes of type 1 rapidly progressive glomerulonephritis

Answer 30

Goodpasture's syndrome - anti-glomerular basement membrane antibody against COL4-A3 (collagen type IV)

Question 31

Describe the appearance of type 1 rapidly progressive glomerulonephritis on fluorescent microscopy

Answer 31

Linear deposition of IgG in the glomerular basement membrane

Question 32

Describe the appearance of type 2 rapidly progressive glomerulonephritis on fluorescent microscopy

Answer 32

Granular IgG immune complex deposition on the glomerular basement membrane and mesangium

Question 33

Describe the appearance of type 3 rapidly progressive glomerulonephritis on fluorescent microscopy

Answer 33

Lack of significant immune complex deposition

Question 34

State the additional organs involved in type 1 rapidly progressive glomerulonephritis

Answer 34

Lungs (pulmonary haemorrhage)

Question 35

State the additional organs involved in type 2 rapidly progressive glomerulonephritis

Answer 35

None (except in SLE)

Question 36

State the additional organs involved in type 3 rapidly progressive glomerulonephritis

Answer 36

Blood vessels (vasculitis, presenting as skin rashes or pulmonary haemorrhage)

Question 37

State the causes of type 3 rapidly progressive glomerulonephritis

Answer 37

Granulomatosis with polyangiitis (c-ANCA), microscopic polyangiitis (p-ANCA)

Question 38

Define Alport's syndrome

Answer 38

Hereditary (X-linked) glomerular disease caused by a mutation in the alpha 5 chain of type IV collagen

Question 39

State the clinical features of Alport's syndrome

Answer 39

Nephritic syndrome, sensorineural deafness, eye disorders (lens dislocation, cataracts)

Question 40

When does Alport's syndrome present?

Answer 40

Age 5-20 with nephritic syndrome progressing to end-stage renal failure

Question 41

Define thin basement membrane disease

Answer 41

Benign familial haematuria - diffuse thinning of the glomerular basement membrane caused by an autosomal dominant mutation in the alpha4 chain of type IV collagen. 5% prevalence, very rarely causes nephritic syndrome - usually incidentally diagnosed with microscopic haematuria