Glomerulonephritides

Question 1

Types of glomerulonephritis

Answer 1

Spectrum from nephrosis (proteinuria due to podocyte pathology) to nephritis (haematuria due to inflammatory damage)
Can be confusing picture as nephritis can lead to nephrosis

Question 2

Renal biopsy preparation

Answer 2

BP <160/95
Hb >9, plt>100
Stop anticoagulants (aspirin 1wk, warfarin to PT<1.2, LMWH 24h)

Question 3

Renal biopsy post-procedure care

Answer 3

Bed rest 4h minimum
Monitor pulse, BP, symptoms, urine colour
Don’t discharge until visible haematuria settled

Question 4

Renal biopsy interpretation

Answer 4

Proportion of glomeruli involved (focal/diffuse)
How much of individual glomeruli affected (segmental/ global)
Hypercellularity
Sclerosis
Immunohistology for deposits (Ig, light chain, complement)
EM for podocytes, deposit locations

Question 5

IgA nephropathy presentation

Answer 5

Asymptomatic non-visible haematuria 12-72h post infection

Slow disease, renal failure in 50% after 30yrs

Question 6

IgA nephropathy diagnosis

Answer 6

Renal biopsy shows IgA deposition in mesangium

Proteinuria <1g

Question 7

IgA nephropathy treatment

Answer 7

RAS blockers reduce proteinuria + protect renal function

Corticosteroids + fish oil if persistent proteinuria >1g after 3-6mths RAS blocker and GFR >50

Question 8

What is HSP

Answer 8

Henoch-Schonlein purpura, small vessel vasculitis with IgA deposition in skin/ joints/ gut in addition to kidney

Question 9

HSP presentation

Answer 9

Purpuric rash on extensor surfaces (typically legs)
Intermittent polyarthritis
Abdo pain
Nephritis

Question 10

HSP diagnosis

Answer 10

Clinical usually
Confirmed with +ve IF for IgA and C3 in skin
Renal biopsy identical to IgA nephropathy

Question 11

HSP treatment

Answer 11

Same as IgA nephropathy for renal disease

Steroids may be used for gut involvement

Question 12

What is Post strep GN

Answer 12

2wks post throat/ 4-6wks post skin infection, strep antigen deposits in glomerulus causing immune complex formation

Question 13

Post strep GN presentation

Answer 13

Haematuria
Acute nephritis (oedema, inc BP, oliguria)

Question 14

Post strep GN diagnosis

Answer 14

Evidence of strep infection

Question 15

Post strep GN treatment

Answer 15

Supportive

Abx to clear nephritogenic bacteria

Question 16

What is Anti-GBM disease

Answer 16

Previously known as Goodpasture’s, auto-Abs to type IV collagen which makes up glomerular and alveolar basement membranes

Question 17

Anti-GBM disease presentation

Answer 17

Oliguria, haematuria, AKI

Pulmonary haemorrhage -> SOB, haemoptysis

Question 18

Anti-GBM disease prognosis markers

Answer 18

Dialysis-dependence at presentation

Increased crescents on renal biopsy indicate poorer prognosis

Question 19

Anti-GBM disease diagnosis

Answer 19

Anti-GBM in circulation/kidney

Question 20

Anti-GBM disease treatment

Answer 20

Plasma exchange
Corticosteroids
Cyclophosphamide

Question 21

Rapidly progressive GN causes

Answer 21

Small vessel/ANCA vasculitis
Lupus nephritis
Anti-GBM disease
IgA/membranous nephropathy may transform to become rapidly progressive

Question 22

Rapidly progressive GN diagnosis

Answer 22

GBM breaks allowing inflammatory cell influx

Crescents seen on renal biopsy

Question 23

Rapidly progressive GN treatment

Answer 23

Corticosteroids
Cyclophosphamide
Treat cause

Question 24

Nephrotic syndrome definition

Answer 24

Proteinuria >3g/24h (P:CR >300, A:CR >250)
Hypoalbuminaemia <30g/L
Oedema

Question 25

Nephrotic syndrome causes

Answer 25

1˚ renal disease: minimal change disease, membranous nephropathy, FSGS 2˚ causes: DM, SLE, myeloma, amyloid, pre-eclampsia

Question 26

Nephrotic syndrome presentation

Answer 26

Generalised pitting oedema | Systemic symptoms from causes of 2˚

Question 27

Nephrotic syndrome management

Answer 27

``` Reduce oedema (<1L fluid/d + salt restriction + diuretics if needed) Treat underlying cause (renal biopsy, steroids first in children as minimal change is most likely) Reduce proteinuria (anti-RAS) Manage complications (VTE, infection, hyperlipidaemia) ```

Question 28

Minimal change disease presentation

Answer 28

Idiopathic or associated with NSAIDs/lithium or paraneoplastic Doesn't cause renal failure

Question 29

Minimal change disease diagnosis

Answer 29

EM shows thinning of podocyte foot processes

Question 30

Minimal change disease treatment

Answer 30

Prednisolone 1mg/kg for 4-16 wks | Frequent relapses managed with inc dose or cyclophosphamide/ calcineurin inhibitors

Question 31

What is FSGS

Answer 31

Commonest GN seen on renal biopsy | Can be 1˚ or 2˚ (HIV, heroin, lithium, lymphoma)

Question 32

FSGS diagnosis

Answer 32

Glomeruli have focal sclerosis on biopsy | If <10 glomeruli in biopsy sample then early disease may be missed

Question 33

FSGS treatment

Answer 33

anti-RAS and BP control Corticosteroids in 1˚ disease Calcineurin inhibitors 2nd line Plasma exchange + rituximab used for recurrence in transplants

Question 34

Membranous nephropathy causes

Answer 34

Idiopathic 1˚ 2˚ to: malignancy (lung, GI, breast, prostate, haem) infection (hep B/C, strep, malaria, schistosomiasis) auto-immune (SLE, RA, sarcoidosis, Sjogren's) drugs (gold, penicillamine)

Question 35

Membranous nephropathy diagnosis

Answer 35

Diffusely thickened GBM due to subepithelial deposits Anti-phospholipase A2 receptor in 75% of 1˚ disease Spikes on silver stain

Question 36

Membranous nephropathy treatment

Answer 36

anti-RAS and BP control Corticosteroids + cyclophosphamide/chlorambucil for those at high risk of progression (proteinuria >4g with no response to anti-RAS over 6 mths or 30% creatinine increase with GFR > 30) Treat underlying cause for 2˚ disease

Question 37

Membranoproliferative glomerulonephritis types

Answer 37

Immune-complex associated - abnormal immune complexes deposit in kidney + activate kidney, often underlying cause e.g. infection/ autoimmune C3 glomerulopathy - Genetic/acquired defect in alternative complement pathway e.g. C3 nephritic factor, progressive kidney dysfunction common

Question 38

Membranoproliferative glomerulonephritis diagnosis

Answer 38

Proliferative glomerulonephritis with electron dense deposits Ig deposition distinguishes between types

Question 39

Membranoproliferative glomerulonephritis treatment

Answer 39

anti-RAS and BP control | Underlying cause in immune-complex disease, immunosuppression trial if none found