renal essay - glomerulonephritis

Question 1

What is glomerulonephritis?

Answer 1

A host-immune response to pathogenic or self antigens which results in immunoglobulins and T cells causing immune deposits in the glomerulus.

Question 2

What are the 3 classes of antigen implicated in glomerulonephritis?

Answer 2

Exogenous bacterial/viral products, exogenous self-circulating products, endogenous glomerular components (in situ)

Question 3

What are the 4 possible locations of immune deposits in the glomerulus in glomerulonephritis?

Answer 3

Subepithelial, subendothelial, mesangial, basement membrane

Question 4

When and why does post-streptococcal glomerulonephritis arise?

Answer 4

Appears 1-4 weeks after a skin/pharyngeal infection with a nephritogenic strain of group A Beta-haemolytic streptococci.

Question 5

Which demographic is most prone to post-streptococcal glomerulonephritis?

Answer 5

Children - however they have the best clinical outcomes

Question 6

Where in the glomerulus are immune deposits found in post-streptococcal glomerulonephritis?

Answer 6

Subendothelial location - deposits found in the basement membrane

Question 7

What syndrome does post-streptococcal glomerulonephritis present with?

Answer 7

Nephritic syndrome

Question 8

What are the symptoms of post-streptococcal glomerulonephritis?

Answer 8

Nephritic symptoms - oliguria, gross haematuria, mild proteinuria, mild-moderate hypertension

Question 9

What does serology show in post-streptococcal glomerulonephritis?

Answer 9

Elevated anti-strep antibodies, low serum C3 due to consumption of complement components

Question 10

What is the histological morphology in post-streptococcal glomerulonephritis?

Answer 10

Enlarged, hypercellular glomerulus, obliterated capillary lumens, cellular proliferation and leukocyte infiltration (neutrophils)

Question 11

What does immunofluuresence microscopy show in post-streptococcal glomerulonephritis?

Answer 11

Granular deposition of IgG, IgM and C3 in capillary walls

Question 12

What is the most common cause of membranous nephropathy?

Answer 12

Auto-immunity to PLA2R receptors on podocytes

Question 13

What is the pathophysiology of membranous nephropathy?

Answer 13

C5b-C9 MAC mediated autoimmunity to PLA2R receptors on podocytes, resulting in the release of proteolytic enzymes that break down foot processes damaging the filtration barrier.

Question 14

Where in the glomerulus are immune complexes deposited in membranous nephropathy?

Answer 14

IgG complexes in subepithelial location, then are incorporated into the basement membrane

Question 15

Why is there no inflammatory cell recruitment and cellular proliferation seen in membranous nephropathy, despite it being an immunological pathology?

Answer 15

Complement C5a and C3a molecules at the podocytes are unable to activate and recruit inflammatory cells as they are not on the capillary side of the basement membrane

Question 16

What syndrome does membranous nephropathy present with?

Answer 16

Nephrotic syndrome

Question 17

What are the signs and symptoms of membranous nephropathy?

Answer 17

symptoms of nephrotic syndrome: massive proteinuria, hypoalbuminaemia, generalised oedema, hyperlipidaemia

Question 18

What types of oedema may be observed in a patient with a nephrotic syndrome?

Answer 18

Pulmonary oedema (orthopnoea, PND), pleural effusion, oedema of lower legs/sacrum

Question 19

Why do nephrotic syndromes cause hyperlipidaemia?

Answer 19

There is increased hepatic lipogenesis as a non-specific response to the falling oncotic pressure secondary to low albumin

Question 20

What is the histological morphology of membranous nephropathy?

Answer 20

Thickened basement membranes with a spiked appearance

Question 21

What are the findings of a immunofluoresence microscopy in membranous nephropathy?

Answer 21

Granular IgG deposits

Question 22

What syndrome does rapidly progressive glomerulonephritis present with?

Answer 22

acute Nephritic syndrome