GN

Question 1

PAN - Polyathritis nodosa

Answer 1

Small micro aneurysms, looks like beads.
Affects medium sized vessels
Associated with Hepatitis B
Symptoms - systemic. Livedo reticulariis, gut - abdo pain and bloody stools, Renal Ischemia, raised BP
Tx = steroids, cyclophosphamide

Question 2

Features of primary Vs secondary FSGS

Answer 2

Primary - true nephrotic syndrome, low albumin, raised UPCR - associated with APOL 1 - Gene
also see podocyte effacement

Secondary - Albumin maintained and UPCR not as high - associated with Infection - HIV, Drugs - Lithium, etc

Question 3

FSGS - What circulatory factor is associated

Answer 3

Circulating glomerular permeability factor

Question 4

3 x organised deposits

Answer 4

Firbillary
Immunotactoid
Amyloid

Question 5

Non organized deposits

Answer 5

Monoclonal immunoglobulin deposition disease -
-Light chain more commonly associated with Kappa
- Heavy chain more commonly associated with Lambda - or AL amyloid

Question 6

What is the commenest type of myeloma

Answer 6

IgG myeloma (70%) and IgA meyloma (30%)

Question 7

AL Amyloid Versus AA Amyloid

Answer 7

AL Amyloid = Misfolded proteins - affects all organs, not just kidneys = Tx Velcade
AA Amyloid - Due to raised amyloid A protein caused by chronic inflammation. Renal involvement = 100% = Tx IL-6 inhibitor such as Tociluzimab

Question 8

Cryoglobulinaemia

Answer 8

Single or multiple immunoglobulins precipitate below 37oC. Cause immune complex deposition, and hyperviscority - depositing in small vessels.
More common in females and associated with hepatitis C
RF positive
Low C4 but normal C3
Cause mesangiocapillary GN

Question 9

Diagnosing Amyloidosis

Answer 9

SAP scan -radioactive scan - goes to the deposited proteins and lights up showing the extent of the disease
Fat pad biopsy

Question 10

Treatment of FSGS

Answer 10

1st line - Steroids for min 6/12
2nd line - CNI ( if no response to steroids after 6 months)
Alternatives = MMF or cyclo

Question 11

Treatment of Membranous Nephropathy

Answer 11

1/3 will resolve spontaneously so watch / wait is reasonable

1st line - Ponticelli
2nd line - Tacrolimus - good at achieving remission but higher relapse rate
3rd Line - Rituximab - good at achieving remission but higher relapse rate

Question 12

Lupus treatment

Answer 12

Induction = Steroids + MMF or Cyclophosphamide
Maintenance = MMF or Aza

Give hydroxychloroquine and supportive treatment as well

In diffuse proliferative GN - give cyclo

Question 13

GPA

Answer 13

PR3 +Ve
cANCA
70% renal involvement
Higher relapse rate
Pulmonary, nose bleeds and eye involvement, hearing loss

Question 14

MPA

Answer 14

MPO positive
pANCA
90% renal involvement
Bronchiectasis and pulmonary fibrosis

Question 15

eGPA

Answer 15

MPO positive
pANCA
Sinus and asthma symptoms
Neurological involvement / mononeuritis multiplex is common
40% renal involvement
Frequent relapse

Question 16

Features of a high risk IgA patient

Answer 16

Increased age
Reduced eGFR
Increase UPCR
Hypertension
Crescents on renal Bx

Question 17

Treatment of Anti-GBM

Answer 17

1) PLEX
2) Steroids
3) Cyclophosphamide

Question 18

How to tell the difference between IgA and post strep infection - in a patient that presents with sore throat, hematuria and renal impairment

Answer 18

IgA nephritis - onset of haematuria and sore throat very quickly together
In post-streptococcal glomerulonephritis the onset of renal disease is usually some time (weeks) after the upper respiratory illness.

Question 19

Types of Membranoproliferative glomerulonephritis
also known as mesangiocapillary glomerulonephritis

Answer 19

Membranoproliferative glomerulonephritis - is a term to describe the pattern of injury
Historically 3 types depending on where the deposits were.

Now the 2 main types:
Type 1 = Immune complex related / IgG mediated disease. Occurs secondary to infection e.g Hepatitis, Autoimmune e.g lupus or myeloma. Tend to subendothelial deposits and IgG and C3 deposition within the mesangum. Associated with cryoglobulinemia. Can be idiopathic.

Type 2 = Dense deposit disease / non IgG mediated disease- now mainly known as C3 glomerulopathy. Deposition of C3 within the glomeruli with little or no staining for immunoglobulin. Low C3/C4

(Type 3 - rare - mainly rare inherited form with disruption to BM)

Question 20

Complements in MCGN

Answer 20

Type 1 = Classical pathway activation. Normal C3, low C4
Type 2 = Alternative pathway - Normal C3 normal C4, plus C3 nephritic factor

Question 21

Features and Treatment of HSP

Answer 21

present 1-3 days post infection of an IgA mucous membrane (e.g pharyngitis or GI).
Painless haematuria and less commonly nephrotic syndrome.
Rash (cutaneous vasculitis), abdo pain (GI vasculitis) - leading to bloody diarrhoea. Arthralgia.
All patients with HTN and proteinuria (>1 g/day) should be started on an ACEi
If the renal Bx shows crescentic GN, then an IS regime similar to that used in renal vasculitis should be started (high dose steroids +/- cyclophosphamide).

Question 22

Lipoprotein glomerulopathy

Answer 22

Rare inherited disease seen in male Japanese patients
Presents with UPCR, nephrotic, ESRD
Mutation of APOE gene
Lipid thrombi accumulate in glomerular capillaries
Stain positive with oil red O stain

Question 23

BP and UPCR aim in IgA

Answer 23

BP 120/80
UPCR <0.5

Question 24

Poor prognostic features in FSGS

Answer 24

Renal impairment
Hypertension
Collapsing variety
High IFTA

Question 25

Btw risk factors in MN - when to anticoagulate

Answer 25

Albumin <20
? > 8g/24hrs

If albumin <25 but another high risk feature e.g Obesity, UPCR >10g)

Question 26

Where are the deposits with the types of membranoproliferative GN

Answer 26

Type 1 - Immune complex = subendothelial immune deposits, associated with hep C / cryo

Type 2- dense deposit disease / C3 GN = mesangial and intramembranous deposits

Question 27

Antibody MCD

Answer 27

Anti nephrin antibodies

Question 28

Proteinuria - Which lambda and kappa associated with which pathology

Answer 28

Kappa LC = Monocolonal IgG deposition disease
Lambda LC = AL amyloid

Question 29

Firbils and the sizes

Answer 29

Amyloid - 8-12nm, randomly arranged - will stain congo red

Fibrillary GN - 12-20nm, random - like amyloid fibrils but don’t stain positive for congo red

Immunotactoid - >30nm, arranged in parallel. hollow, associated with haematological maligancy

Question 30

Which cause of deposits: - Subendothelial / Subepithelial / Intramembranous / Mesangial

Answer 30

Subendothelial
- lupus class 3-4 / MPGN

Subepithelial
- Membranous / Infection / Class 5 lupus

Intramembranous
- Dense deposit disease / C3

Mesangial
- IgA

Question 31

Risk factors and features of Nodular glomerulosclerosis

Answer 31

Commonly seen in patients with smoking and hypertension history

Looks like diabetic nephropathy on Bx but no history of DM

Biopsy = Linear IgG, thickened BM and foot process effacement.

Question 32

Myeloma Kidney = Cast nephropathy - features

Answer 32

Increased LC reacts with Tamm-Horsfall in DCT = forms plug and tubular / interstitial injury
On Bx = Fractured casts with increased cells around it. Massons trichrome positive for monoclonal LC + congo red positive

Question 33

Monoclonal Immunoglobulin deposition disease - features

Answer 33

Deposition in BM and tubules
Different to Amyloid - as fibrils are non-organized and negative for congo red

Types
-Light chain - often Kappa
-Heavy chain - often lambda
-Both heavy and light chain

Patients present with proteinuria, hematuria, raised BP and renal impairment

Biopsy features = nodular sclerosising GN, Linear staining along GBM and tubules for LC/HC or LHC, non organized fibrils
Appearances can look similar to DN but IF positive for monoclonal LC

Question 34

Indication for steroids and cyclophosphamide in IgA nephropathy

Answer 34

> 50% crescents
Rapidly progressive GN

Note - MMF in Chinese patients