Glomerulonephritis

Question 1

What does focal mean with regards to glomerulonephritis?

Answer 1

affecting only some glomeruli

Question 2

What does diffuse mean with regards to glomerulonephritis?

Answer 2

affecting all glomeruli

Question 3

What does segmental mean with regards to glomerulonephritis?

Answer 3

affecting only part of glomerulus

Question 4

What does global mean with regards to glomerulonephritis?

Answer 4

affecting whole glomerulus

Question 5

What does proliferation mean with regards to glomerulonephritis?

Answer 5

increase in number of cells

Question 6

What does expansion mean with regards to glomerulonephritis?

Answer 6

increase in intercellular matrix

Question 7

What does crescent mean with regards to glomerulonephritis?

Answer 7

proliferation of cells within Bowman’s space

Question 8

Describe some mechanisms underlying glomerulonephritis

Answer 8

Immunological:
- antibody binding to intrinsic glomerular antigens eg. Goodpasture’s disease

• antibody binding to ‘planted’ glomerular antigens eg. post-strep glomerulonephritis
• deposition of circulating antigen-antibody complexes eg. lupus nephritis
• non-specific deposition of circulating antibody eg. IgA nephropathy

Vascular:
- ‘pauci-immune’ capillary inflammation (eg. systemic vasculitis)

Question 9

Indications for renal biopsy

Answer 9

nephrotic syndrome (adults)
renal dysfunction of unknown cause (particularly acute)
to guide treatment or assess prognosis when diagnosis known
dysfunction of transplant kidney
(haematuria)
(proteinuria)

Question 10

Complications of renal biopsy

Answer 10

pain
bleeding

Question 11

Absolute/relative contraindications to renal biopsy

Answer 11

abnormal clotting/thrombocytopenia
drugs (aspirin, clopidogrel, warfarin, DOACs etc)
uncontrolled hypertension (>170/100)
single kidney
hydronephrosis
UTI (pyelonephritis)

Question 12

How are renal biopsies interpreted?

Answer 12

light microscopy
immunostaining (looks for immunoglobulin or complement components)
electron microscopy (ultrastructural detail including immune deposits)

Question 13

Modes of presentation of renal disease

Answer 13

haematuria
proteinuria
hypertension
nephrotic syndrome
nephritic syndrome
AKI
CKD

Question 14

Nephrotic syndrome signs/symptoms

Answer 14

proteinuria
hypoalbuminaemia
oedema

Question 15

Describe minimal change disease

Answer 15

commonest cause of nephrotic syndrome in children
electron microscopy = fusion of podocyte foot processes
steroid-responsive
usually idiopathic

Question 16

What is the commonest cause of nephrotic syndrome in children?

Answer 16

minimal change disease

Question 17

Minimal change disease causes

Answer 17

usually idiopathic
drugs (eg. NSAIDs)
lymphoma

Question 18

How does focal segmental glomerulosclerosis (FSGS) present?

Answer 18

nephrotic syndrome +/- renal impairment
focal involvement of kidney - may be missed on biopsy

Question 19

Causes of focal segmental glomerulosclerosis

Answer 19

obesity
IV heroin use
HIV
drugs (eg. pamidronate)

Question 20

What is the commonest cause of nephrotic syndrome in adults?

Answer 20

membranous nephropathy

Question 21

What does histology show in membranous nephropathy?

Answer 21

spikes on basement membranes
IgG deposition

Question 22

What conditions/causes is membranous nephropathy associated with?

Answer 22

malignancy (solid organ -> lung, colon, breast)
drugs (eg. gold, penicillamine, captopril)
infections (eg. hepatitis, malaria)

Question 23

How can mesangiocapillary glomerulonephritis present?

Answer 23

several ways –> including nephrotic and nephritic syndromes
can recur following transplantation

Question 24

Biopsy findings in mesangiocapillary glomerulonephritis

Answer 24

mesangial proliferation
thickened capillary walls
‘double contouring’ of basement membrane
positive immunofluorescence (eg. C3)

Question 25

What conditions is mesangiocapillary glomerulonephritis associated with?

Answer 25

infections (hepatitis, malaria, endocarditis, shunt nephritis) cryoglobulinaemia malignancy

Question 26

How does diabetic nephropathy present?

Answer 26

patients usually have other microvascular complications eg. retinopathy, peripheral neuropathy earliest feature = low level proteinuria ('microalbuminuria') proteinuria then becomes heavier

Question 27

What does histology show in diabetic nephropathy?

Answer 27

Kimmelstiel-Wilson lesions (nodular glomerulosclerosis)

Question 28

How can amyloidosis affecting the kidneys present?

Answer 28

heavy proteinuria +/- nephrotic syndrome +/- renal failure

Question 29

What stain is used for amyloidosis?

Answer 29

congo red - apple green birefringence under polarised light

Question 30

What are the 2 subtypes of amyloidosis?

Answer 30

AL - light chain deposition (eg. myeloma) AA - chronic inflammation (eg. infection, connective tissue disorders)

Question 31

What is the commonest form of glomerulonephritis?

Answer 31

IgA nephropathy (Berger's disease)

Question 32

What occurs in IgA nephropathy?

Answer 32

deposition of circulating IgA within mesangium leading to expansion of mesangial matrix and mesangial cell proliferation

Question 33

IgA nephropathy presentations

Answer 33

asymptomatic microscopic haematuria episodic macroscopic haematuria (eg. exercise, respiratory tract infection) progressive renal impairment, end stage renal failure

Question 34

What is a nephritic pattern?

Answer 34

hypertension haematuria renal impairment (oedema)

Question 35

When does post-streptococcal glomerulonephritis occur?

Answer 35

2-3 weeks after group A streptococcal infection (throat, skin) usually presents as nephritic illness

Question 36

How is post-infectious glomerulonephritis treated?

Answer 36

supportive treatment

Question 37

Which vasculitides are more likely to affect the kidneys?

Answer 37

small vessel

Question 38

Systemic vasculitis affecting kidneys signs on biopsy

Answer 38

focal necrotising glomerulonephritis +/- crescents pauci-immune

Question 39

Antibody present in Goodpasture's disease

Answer 39

anti-GBM (glomerular basement membrane)

Question 40

How does Goodpasture's disease present?

Answer 40

AKI and/or pulmonary haemorrhage

Question 41

Goodpasture's disease biopsy findings

Answer 41

focal necrotising glomerulonephritis +/- crescents linear antibody deposition

Question 42

Goodpasture's disease treatment

Answer 42

may respond if treated early - immunosuppression +/- plasma exchange

Question 43

How does rapidly progressing glomerulonephritis (crescentic nephritis) present?

Answer 43

nephritic illness with rapidly deteriorating renal function (can be caused by systemic vasculitis and Goodpasture's disease)

Question 44

Rapidly progressing glomerulonephritis renal biopsy findings

Answer 44

acute inflammatory process with crescent formation - cellular proliferation in Bowman's space

Question 45

Investigations to consider in patients with glomerular disease

Answer 45

Urine: - dipstick - microscopy - culture - protein quantification blood: - FBC, ESR, coag, blood film, U&E, LFT, Ca, PO4, CRP - autoantibodies (ANA, ANCA, anti-GBM) - serum immunoglobulins and electrophoresis - serum free light chains - cryoglobulins - complement levels - blood cultures - serology (hepatitis B/C, HIV, ASO titre) renal biopsy