Pathology

Question 0

Where are the four sites for glomerular injury?

Answer 0

Subepithelial affects podocytes/podocyte side of basement membrane

Within glomerular basement membrane

Sub endothelial - inside basement membrane

Mesangial/paramesagial - supporting the capillary loop

Question 1

What problems can occur with the glomerular filter and signs of this?

Answer 1

Get blocked -> renal failure

• hypertensive
• haematuria

Can leak

• proteinuria (albumin)
• haematuria

Can both occur together

Question 2

What is proteinuria

Answer 2

Presence of excess serum proteins in urine

Question 3

What allows proteins to leak through the filtration barrier?

Answer 3

Podocyte damage

• widening of fenestration slits
• causes proteins to be leaked when they would normally not be filtered

Question 4

Causes of nephrotic syndrome/proteinuria?

Answer 4

Minimal change glomerulonephritis
Minimal change focal glomerulosclerosis
Membranous glomerulonephritis

Question 5

When is minimal change glomerulonephritis seen?

Answer 5

Childhood/adolescence

Decreasing incidence with age

Question 6

What happens in minimal change glomerulonephritis?

Answer 6

Podocyte damage mediated by T cells

Under light microscope, appears normal, under electron microscope, can see podocyte damage

Question 7

How is minimal change glomerulonephritis treated?

Answer 7

Steroids

Relapse common if stopped

Question 9

What does each part of the name focal segmental glomerulosclerosis mean?

Answer 9

Focal - involves

Question 10

What happens in focal segmental glomerulosclerosis?

Answer 10

Podocytes undergo damage and subsequent scarring
-> protein in urine

Caused by a circulating factor (because transplanted kidneys undergo the same damage)

Question 10

What is the commonest cause of nephrotic syndrome in adults?

Answer 10

Membranous glomerulonephritis

Question 11

What can focal segmental glomerulosclerosis lead to?

Answer 11

Renal failure

Question 12

What happens in membranous glomerulonephritis?

Answer 12

Immune complex deposits in sub-epithelial space
Autoimmune basis caused by an auto-antibody to podocytes

Evidence that it may be secondary because it is associated with other conditions such as lymphoma

Question 13

Prognosis of membranous glomerulonephritis?

Answer 13

Rule of thirds

• third will remit
• third will continue in nephrotic state
• third will show progressive loss of renal function

Question 14

What is nephritic syndrome?

Answer 14

Renal failure due to blocking of the filter

Question 15

What can cause nephritic syndrome?

Answer 15

IgA nephropathy

Hereditary nephropathies

• Thin GBM nephropathy
• Alport

Diabetes mellitus

Goodpasture’s syndrome

Vasculitis

Question 16

What is the most common glomerular nephropathy?

Answer 16

IgA nephropathy

Can happen at any age

Question 17

What happens in IgA nephropathy?

Answer 17

Deposition of IgA antibodies in the glomerulus

Can lead to mesangial proliferation and scarring

Question 18

Presentation of IgA nephropathy?

Answer 18

Visible/invisible haematuria
Some patients have proteinuria
Relationship with mucosal infections
Significant number progress to renal failure

Question 19

Treatment of IgA nephropathy?

Answer 19

None

Question 20

What is thin glomerular basement membrane nephropathy? Features?

Answer 20

A benign familial nephropathy
Isolated haematuria
Thin GBM
Benign course

Question 21

What is Alport?

Answer 21

X linked causing abnormal collagen IV production
Get abnormal appearance of GBM a
Can progress to renal failure

Question 22

What is Alport associated with?

Answer 22

Deafness

Question 23

How can diabetes mellitus lead to nephritic syndrome?

Answer 23

Microvasculature is damaged which damages the glomerulus

Get expansion of mesangium with collagen deposition - mesangium sclerosis

Thickening of the basement membrane (4.5x of normal)

Question 24

What causes diabetes mellitus to lead to nephritic syndrome?

Answer 24

infections

abnormality of blood supply from atheroma or microvascular disease

Question 25

What is seen in nephritic syndrome caused by diabetes?

Answer 25

Progressive proteinuria

Progressive renal failure

Question 26

What is Goodpasture’s syndrome characterised by?

Answer 26

Acute onset of severe nephritic symptoms
Combination of glomerulonephritis with pulmonary (alveolar) haemorrhage -> haemoptysis
Deposition of IgG

Question 27

Pathology of Goodpasture’s syndrome?

Answer 27

Circulating anti-glomerular basement membrane antibodies bind to basement membranes (collagen IV) in lungs and kidney, fix complement and trigger a cell-mediated inflammatory response

This causes glomerulonephritis and pulmonary capillaries

Question 28

Pre-disposing factors of Goodpasture’s syndrome?

Answer 28

HLA-DR2 gene
Smoking
Influenza
Exposure to organic solvents or hydrocarbons 
Codeine inhalation 
Metal dusts

Question 29

How do you treat Goodpasture’s syndrome?

Answer 29

Immunosuppression

Plasmaphoresis if caught early

Question 30

What is vasculitis?

Answer 30

Inflammation of blood vessels

Question 31

How does vasculitis lead to nephritic syndrome?

Answer 31

Blood vessels in the glomerulus see attack end and become inflamed by neutrophil cytoplasmic antibody (ANCA)

Question 32

What is the mechanism for getting sub-epithelial deposits?

Answer 32

Antigen on podocytes abnormally recognised
Circulating IgG binds to it, forming immune complexes in the glomerulus
Eg membranous glomerulonephritis

Question 33

What is the mesangium?

Answer 33

Cells continuous with the smooth muscle of the arteriolar wall in the afferent arteriole in the glomerulus. Not blocked by podocytes.

Question 34

Mechanism for mesangial deposits?

Answer 34

Immune complexes are deposited directly into the mesangium as there are no podocytes or basement membrane to act as a barrier