Glomerulonephritis Flashcards
What is glomerular disease?
general term for a group of diseases which affect the glomeruli of the kidneys
What is glomerulonephritis?
Inflammation of the glomeruli
What bedside tests can be used to detect renal disease?
Urine dip - look for glomerular disease. Severely increased albuminuria >300mg/24hrs is the level at which standard dipstick tests become positive.
BP - inappropriate salt and water retention
What is the cause of GN?
due to an immunologic response to a variety of aetiologic agents which are largely unknown
What blood tests are done in GN? (11)
FBC, U&E, LFT, CRP, immunoglobulins, electrophoresis, complement (C3, C4), autoantibodies: ANA, ANCA, anti-dsDNA, anti-GBM; blood culture, ASOT (anti-stretopcoccal antibodies titre), hepatitis serology
What 6 urine tests are performed in a patient with suspected GN?
Microscopy, culture & sensitivity (MC&S), Bence-jones proteins, ACR/PCR, RBC casts
What imaging and further tests are performed?
CXR (pulmonary haemorrhage), renal USS.
What is the triad of nephrotic syndrome?
Triad of Heavy proteinuria (3.0g protein lost in urine per day) + hypoalbunaemia + oedema.
What are the signs of nephrotic syndrome?
frothy urine, anasarca, hypoalbuminaemia, increased lipid synthesis, hyper-coaguable state
What are complications of nephrotic syndrome?
wasting, AKI, DVT/PE, hyperlipidaemia, increased CVD risk, increased infection risk
How is nephrotic syndrome managed? (6)
Fluid and salt restriction and loop diuretics to reduce oedema
Treat underlying cause
ACEI/ARB to reduce proteinuria
Heparin & warfarin - VTE risk
Pneumococcal vaccine
Statins
What is treatment of minimal change disease?
Corticosteroids, cyclosporine/tacrolimus
What is FSGS?
Scarring (sclerosis) in glomerulus - with only some glomeruli affected (focal) and only parts of individual glomerulus affected (segmental)
What is membranous Glomerulonephritis?
Immune deposits on basement membrane and a second membrane forms over these deposits with irregular spikes where several immune complexes deposited
How is membranous Glomerulonephritis diagnosed?
Anti-phospholipase A2
Diffusely thickened GBM due to subendothelial deposits.
What causes nephritic syndrome?
Complexes lodge itself in the capillaries and illicit an immune response against the capillaries. There is an inflammatory response which causes endothelial cell loss and this allows RBCs, WBCs and protein to cross the glomerulus
What are is triad of nephritic syndrome?
Haematoproteinuria, salt + water retention, impaired renal function
What are signs and symptoms of nephritic syndrome? (4)
urine dip –> haematuria + pyuria
Oliguria
High BP
Granular casts
What is Post-streptococcal GN?
The inflammation of the glomerulus after a streptococcal infection.
Usually affects children. Happens 6 week after skin infection (impetigo) or 1-2 weeks after pharyngitis
What is the pathogenesis of Post-streptococcal GN?
1) The bacterium initiates a type III hypersensitivity reaction
2) Immune complexes are formed with IgG/IgM antibodies which travel to the glomeruli and become trapped in the GBM
3) The complexes initiate an inflammatory reaction in the glomerulus
What are the 3 blood tests for Post-streptococcal GN?
Blood: Anti-DNase B, anti-step antibody titre (ASOT), decreased C3
What is treatment of Post-streptococcal GN?
Supportive + antibiotics
What is IgA nephropathy?
A type of nephritic syndrome. Most common cause of GN characterized by deposition of the IgA antibody in the glomerulus.
What are the signs of IgA nephropathy? (4)
Macroscopic Haematuria
Associated with URTI (occurs 1-2 days after)
Hypertension
slow, progressive renal function loss and eventual ESRD
How IgA nephropathy diagnosed? (2)
Biopsy - Mesangial IgA deposits
Urinanalysis - erythrocytes, mild proteinuria
What is the treatment of IgA nephropathy?
ACE-I/ARBs when patient develops HTN or proteinuria of >0.5g/day
Proteinuria >1g/day –> corticosteroids + fish oil
What is Henoch-Schonlein purpura?
Systemic vasculitis that often arises in response to an infectious trigger. Characterised by IgA deposits in skin, joints, gut and kidney
How does Henoch-Schonlein purpura present? (4)
The characteristic petechial rash typically affecting buttocks and lower legs
Abdominal pain
polyarthritis
Haematuria (Similar to IgA)
How is Henoch-Schonlein purpura diagnosed?
Clinical and confirmed by immunofluorescence for IgA and C3 in skin
What is Rapidly Progressive GN (RPGN)?
It is characterised by rapid loss of renal function over days to weeks. Renal biopsy shows crescentic lesions, often associated with necrotising lesions within the glomerulus, termed focal segmental (necrotising) glomerulonephritis.
What is Type 1 RPGN?
Goodpasture’s disease.
What is Anti-GBM disease/Goodpasture’s Disease?
A disease where there is the development of antibodies to type IV collagen which is in the glomerular basement membrane (anti-GBM antibodies). Linear IgG appearance on immunofluorescence.
What is type II RPGN?
It is caused by post-streptococcal glomerulonephritis, SLE, IgA nephropathy, henoch-schonlein purpura. Granular appearance on IF due to immune complex deposition in subendothelium.
What is Type III RPGN?
This is pauci immune RPGN with a negative IF. Associated with Anti-neutrophilic cytoplasmic antibodies (ANCAs) in blood.
What is cANCA associated with?
Wegener’s Granulomatosis
what is pANCA associated with?
Churg-Strauss syndrome
How is RPGN managed?
Corticosteroids + Cyclophosphamide
How does Anti-GBM disease present?
Renal disease, lung disease (pulmonary haemorrhage), dialysis. Dependence at + increased crescents on biopsy equates to a poor prognosis.
What is the treatment of Anti-GBM disease?
Plasma exchange, corticosteroids, cyclophosphamide
How does Autosomal dominant polycystic kidney disease (ADPKD) present?
- Renal failure (most common cystic disease to cause it)
- Pain in right side and flank
- Cyst infection
- Abdo exam - nodular kidney
What is the screening for ADPKD?
Annual BP, urine dip and renal function check, USS
Where are sites of extra-renal cysts in ADPKD?
berry aneurysms, liver, pancreas, spleen cysts, mitral valve prolapse, diverticuli
A 15-year-old girl presents with a palpable purpuric rash over her lower limbs accompanied by polyarthralgia following a recent sore throat. What is the most likely diagnosis?
Henoch-Schonlein purpura
A 30-year-old Asian woman presents with a history of headaches, claudication and having unequal blood pressure in both her arms. Given the most likely diagnosis, which renal feature may develop?
Renal artery stenosis, which is associated with Takayasu’s arteritis
How is GN diagnosed?
Renal biopsy
What are the 3 main nephritic syndromes?
IgA Nephropathy (Berger’s), Alport syndrome, rapidly progressive GN
What are 5 main nephrotic syndromes?
Minimal change, FSGS, amyloidosis, diabetic nephropathy, membranous GN
What are the discerning features between IgA nephropathy and post-strep GN? (3)
post-streptococcal glomerulonephritis is associated with low complement levels
main symptom in post-streptococcal glomerulonephritis is proteinuria
interval (1-2 weeks) between URTI and the onset of renal problems in post-streptococcal glomerulonephritis
How does Goodpasture’s present?
Pulmonary haemorrhage, RPGN
When RBCs when examined under the microscope, when are they more commonly dysmorphic in kidney disease?
RBCs leaking form the glomeruli
When is renal USS performed?
To rule out urinary tract obstruction
What is Tolvapatan indictaed for?
ADPKD
What precautions need to be taken with Tolvapatan? (3)
Patients need to drink plenty of fluids, regular blood tests (renal + liver function), annual MRI volume measurement of kidneys
