Glomerulonephritis Flashcards
Glomerulonephritis definition
inflammatory diseases involving the glomerulus and tubules
Nephrotic syndrome features:
“protein leac” (lipidaemia,oedema, albumin down, chol increases)
- Proteinurea (>3.5g in 24 hours)
- hypoalbuminaemia (<25g/l)
- peripheral oedema
- Hyperlipidaemia - total cholesterol >10mmol/l
Albumin is lost in the urine, due to gaps in podocytes allowing proteins to escape.
Oedema - due to loss of albumin, intravascular oncotic pressure decreases, fluid moves out of vessels
Hyperlipidaemia- hypoalbuminaemia, liver compensates by increasing production of lipids, hence causing hyperlipidaemia
Causes of Nephrotic syndrome
Primary
- minimal change glomerulonephritis - the most common cause of nephrotic syndrome in children
- membranous glomerulonephritis
- focal segmental glomerulosclerosis - the most common cause of nephrotic syndrome in adults
Secondary
- D - diabetes
- A - Amyloidosis
- V- vasculitis
- I - infections (syphillus, hep B_
- D- drugs
(SLE, malignancy, HIV)
Nephritic syndrome features
Blood +++ (microscopic or macroscopic)
Red cell casts- distinguishing features, form in nephrons and indicate glomerular damage
- Haematuria
- proteinuria (small amount)
- hypertension
- low urine volume <300ml/day
Causes of nephritic syndrome
Post sterptococcal glomerulonephritis - appears weeks after URTI
IgA nephropathy - appears within a day or two after URTI
Rapidly progressive glomerulonephritis (cresentic glumerulonehritis)
- Good pastures - anti-GBM Ab against basal membrane antigens
- vasculitic disorder- wegners, microscopic polyangitis
Tests for Glomerulonephritis
U&Es - creatinine for renal impairment
FBC- anaemia, infection
ESR, CRP- markers of inflammation (infectious cause_
EP and IG - IgA increased in IgA nephropathy EP rules out myeloma
Serum biochemistry- renal function, liver function, bone profile, lipids, glucose
Autoantibodies and complement
- ANCA- wegers granulomatosis + polyarterial nodosum
- Anti-GBM - good pastures
- ANF- lupus
Urinalysis, Urine PCR
- RBC casts, proteinuria
Coagulation screen
- biopsy (are they able to clot)
Imaging - CXR, US
- infection, pulmonary renal syndrom
LFTs (albumin levels)
GI - diabetes, commonest cause of all nephrotic syndromes
Feautures of IgA nephropathy
- Commonest cause of GN in the world
- may be secondary to:
- Henoch-schloen purpura
- cirrhosis
- coeliac disease
- may present with one or all
IgA nephropathy Clinical presentation
- Haematuria - increased destruction of GBM
- proteinuria
- hypertension
- renal impairment
Diagnosis of IgA nephropathy
- Electronmicroscopy - shows immune complexes in the GBM
- Immunofluorescence- shows IgA deposition
- Light microscopy- proliferation of mesangium
Pathophysiology of IgA nephropathy
- overproduction of IgA could be triggered by infection
- IgA deposition in the mesangium + C3 deposition
- Lysis of mesangium - Proliferation and activation of mesangial cells causing production of matrix - inducing glomerulosclerosis and scarring
- result is tubular loss, glomerulosclerosis and hypertensive damage
- Spillage of protein and blood cells into the urine
Treatment of IgA nephropathy
- No specific treatment
- Anti-hypertensives, ACE inhibitors
Outcomes of IgA nephropathy
- resolution
- Perists
- progression to ESRF 1/3
Membranous Glomerulonephropathy Clinical feautres
- proteinuria without haematura
- hypertension
- renail impairment
- Nephrotic syndrome!
Pathophysiology of Membranous glomerulonephritis
- Trigger may be Ag from tumour, infections, drugs
- Production of immune complexes, stuck in GBM
- alters GBM charg, permeability selectivity and thickened GBM
- Results in glomeruloscerlosis, tubular loss and hypertensive damage
- leads to loss of protein in urine = hallmark
Features of membranous GN