Glomerulonephritis Flashcards
Define glomerulonephritis.
Glomerulonephritis encompasses a number of conditions which
- are caused by pathology in glomerulus
- present with haematuria, proteinuria or both
- are diagnosed on renal biopsy
- cause CKD
- can progress to kidney failure (except with minimal change disease - MCD)
What are the 2 main consequences of glomerular inflammation and how do these present?
- Loss of barrier function –> proteinuria (mild to nephrotic syndrome) and haematuria (mild to macrocytic)
- Loss of filtering capacity –> reduced excretion causing accumulation of waste products (AKI)
What are the risk factors for glomerulonephritis?
- Group A beta-haemolytic strep
- Resp infection
- GI infection
- Hep B and C
- Infective endocarditis
- HIV
- SLE
- Systemic vasculitis
- Hodgkin’s lymphoma
- Lung cancer
- Colorectal cancer
- non-Hodgkin’s lymphoma
- Leukaemia
- Thymoma
- Haemolytic uraemic syndrome
- Drugs - penicillamine, gold sodium thiomalate, non-steroidal anti-inflammatory drugs, captopril, mitomycin C, cocaine, and anabolic steroids.
Briefly describe the range of glomerular diseases.
Spectrum ranges from proteinuria (nephrosis) to haematuria (nephritis).
List 5 causes of glomerulonephritis.
- IgA nephropathy - commonest cause worldwide
- HSP - variant of IgA with systemic involvement (skin, connective, GI, scrotum)
- Anti-GBM (Goodpasture’s) - crescentic GN, auto-Ab to type IV collagen. Bind to alveolar BM –> lung haemorrhage.
- Post streptococcal GN - 1-12 weeks after throat/skin infection
- Pauci-immune - commonest cause of GN - +ve ANCA but negative immunofluorescence
What are the signs and symptoms of glomerulonephritis?
- Asymptomatic haematuria +/- proteinuria
- Nephrotic syndrome: heavy proteinuria, hypoalbuminuria, fluid retention
- Nephritic syndrome : haematuria, proteinuria, fall in GFR, salt and water retention and hypertension
- Rapidly progressive GN - rapid loss of renal function such as ESKD within weeks or months
- Chronic GN - slow deterioration in renal function, over several years with haematuria, proteinuria, hypertension.
What investigations would you do for glomerulonephritis?
Oliguria, urine casts, crescents (if AKI results),
-
Bloods
- FBC - normocytic normochromic anaemia
- Lipid profile - hyperlipidaemia or normal
- U&Es, CRP, Complement (C3, C4)
- Autoantibodies (ANA, ANCA, anti-dsDNA, anti-GBM), blood culture, ASOT
- Serum albumin - low
- LFTs - elevated e.g. in Hep C or B
- GFR - reduced in CKD
- Urine MC&S - Bence Jones protein, RBC casts (+dysmorphic RBCs) , haematuria, proteinuria, leukocytes
- A:CR (spot urine albumin: creatinine ratio) - normal urine ACR is <220mg/mmol. May be raised in GN.
Imaging
- CXR - pulmonary haemorrhage
- Renal USS - size and anatomy for biopsy, may be small in chronic process
- Biopsy - renal biopsy required for diagnosis
What are the 4 types of severity of glomerulonephritides?
- Minimal change
- Diffuse - affecting all glomeruli
- Focal - affecting only some glomeruli
- Segmental - only affecting parts of an affected glomerulus
What is the management of GN?
Management: not on Sofia
- Refer specialist
- BP management – <130/80
- ACE-I or ARB – reduce proteinuria and preserve renal function
- Steroids/immunosuppression
- Treat underlying cause
Why are ACEi/ARB useful in GN?
Reduce intraglomerular pressure by inhibiting AGII efferent vasoconstriction
Usually angiotensin acts to constrict both afferent and efferent arterioles but preferentially efferent.
What are the types of crescentic glomerulonephritis?
Immune complex associated
Anti GBM
Pauci-immune
What are the types of immune complex associated glomerulonephritis?
SLE
IgA nephropathy
Post-infectious glomerulonephritis
What are the types of non-immune complex associated glomerulonephritis? (nephrotic syndrome)
MCD
FSGS
What are the differences between treatment of MCD and FSGS?
MCD - generally responds to immunosuppression
FSGS - less likely to respond to immunosuppression
What is the antibody target in MGN?
Phospholipase A2
How common is diabetic nephropathy?
Affects 30-40% of diabetics
What are the stages of diabetic nephropathy?
Stage 1 - thickened BM
Stage 2 - more mesangial matrix
Stage 3 - nodular lesions (Kimmelstiel Wilson)
Stage 4 - advanced glomerulosclerosis
What is the most common glomerulonephritis?
IgA nephropathy - from immune complex deposition
What is the management of IgA nephropathy?
- Observation and follow up = isolated haematuria, no or minimal proteinuria (<500mg/day), and a normal GFR
- ACEi = if persistent proteinuria (>500mg/day), a normal or only slightly reduced GFR
- Corticosteroids = if there is active disease (e.g. falling GFR) or failure to respond to ACEi
What is the prognosis with IgA nephropathy?
25% → ESRF
Frank haematuria is a good prognostic factor
Poor prognosis if male, >2g/day proteinuria, HTN, smoking, hyperlipidaemia, ACE genotype DD
What is the management of MCD?
Oral corticosteroids - helps in 80% of cases
Cyclophosphamide if steroid resistant
What is the prognosis with MCD?
- 1/3 have just one episode
- 1/3 have infrequent relapses
- 1/3 have frequent relapses which stop before adulthood
What is the management of FSGS?
- Steroids +/- immunosuppressants
What is the prognosis with FSGS?
Untreated FSGS has a < 10% chance of spontaneous remission
What is the management of membranous glomerulonephritis?
ACEi or ARB - reduce proteinuria and improve prognosis
Immunosuppression (corticosteroid AND another agent)- only for those with severe disease; many improve without this. Corticosteroid alone not effective.
Anticoagulation - for high risk patients
What is the prognosis with MGN?
- one-third: spontaneous remission
- one-third: remain proteinuric
- one-third: develop ESRF
What is the management of diabetic nephropathy?
Dietary protein restriction
Tight glycaemic control
BP control <130/80
ACEi or ARB - start when ACR is 3mg/mmol
Statin - controls dyslipidaemia
What is the management of post-streptococcal glomerulonephritis?
Penicillin G - eradicates the nephrogenic strain
Manage hypertension and oedema
What is the prognosis with post-streptococcal glomerulonephritis?
>90% of children make a full recovery
Adults have a worse outcome due to renal function impairment
What is the management of anti-GBM?
Plasmapheresis
Steroids
Cyclophosphamide
What are the complications of anti-GBM?
One of the main complications is pulmonary haemorrhage.
