Acute nephritis, glomerulonephritis and acute tubular necrosis Flashcards
Nephritic syndrome definition
Characterised by:
- Haematuria
- Proteinuria
- Leucosuria
Acute interstitial nephritis
- Description
- Causes
Inflammation of the renal interstitium (between renal tubules)
- Commonly caused by hypersensitivity to medication
Causes:
- Drug allergy: antibiotics (beta-lactam, fluroquinolones)
- PPIs
- NSAIDs
- Chemo
- AI/ inflammatory disease: Sjorgren, TINU, sarcoid
- Infective: staph, strep, Brucella.
Acute interstitial nephritis
- Presentation
Mild renal impairment
- Poor renal function= worse prognosis
If drug reaction, allergy picture
- Rash, fever, peripheral eosinophilia.
Oedema
- if NSAIDs used, presents with nephrotic syndrome
Investigations for acute interstitial nephritis
Definite diagnosis= biopsy
- Inflammatory cell infiltrate in interstitium
Nephritic causes of glomerulonephritis
IgA nephropathy
Post-infectious GN
Rapidly progressive GN
Rapidly progressive GN
- Description
- Causes
Characterised by rapid decrease in eGFR
Causes
- Type 3: ANCA related vasculitis: granulomatosis with polyangitis (Wegner’s), microscopic polyangiitis
- Type 1: anti-GBM autoantibodies= Goodpasture syndrome,
Type 2: Immune complex deposition: SLE, IgA nephropathy
Treatment of Rapidly progressive GN
Rituximab
Corticosteroids
Cyclophosohamide
- azathioprine
Post-infectious GN
- Description
- Histology
- Causes
Type 3 hypersensitivity reaction
- Antibodies bind to sites on glomerulus and activates complement
Histology
- Proliferative GN: proliferation of endothelium and mesangium.
Causes
- Streptococcal infection (weeks post-infection)
Pathophysiology of acute tubular necrosis
Ischaemia or nephrotoxic injury to the renal tubules leading to death of tubular endothelial cells.
Acute tubular necrosis causes
Reduced perfusion
- Dehydration
- Circulatory shock
- Massive haemorrhage
Nephrotoxins
- Aminoglycoside antibiotics
- Contrast dye
- Rhabdomyolysis
The most common pathological cause of an AKI is…
Acute tubular necrosis
State the phases of acute tubular necrosis
Oliguria/anuric phase
- Damage to tubular cells= less filtration and urine production
Polyuric phase
- Tubular cells are regenerated, leading to increased urine production
Recovery phase
- Urine output returns back to baseline
Urinalysis findings for acute tubular necrosis
“Muddy brown casts”
Proteinuria
Urine osmolality <350
Histopathological findings of acute tubular necrosis
Necrotic, epithelial tubular cells
- loss of nuceli
Detached tubular cells
Dilated tubules
Chronic interstitial nephritis is most commonly caused by…
Prolonged use of NSAIDs
Urine studies findings for interstitial nephritis
May show eosinophilia in hypersensitivity reaction
White cell casts
Proteinuria, haematuria
Kidney ultrasound in interstitial nephritis will show…
Increased cortical echogenicity
IgA nephropathy is also known as…
Berger’s disease
Causes/ associations of IgA nephropathy
Upper respiratory tract infection
- Typically occurs within days
Coeliac disease
HIV
Alcoholic liver disease
IgA nephropathy presentation
Nephritic syndrome
Macroscopic haematuria
AKI
Nephrotic syndrome causes of glomerulonephritis
- Minimal change disease
- Focal segmental glomerulosclerosis
- Membraneous GN
- Membranoproliferative GN
Nephritic syndrome causes of glomerulonephritis
Mesangial proliferative/ IgA nephropathy
Post-infectious/ diffuse proliferative GN
Rapidly progressive/ crescentic GN
Focal segmental glomerulosclerosis (FSGS) pathology
Segmental glomerular scarring and podocyte damage.
Renal biopsy in minimal change disease will show
Loss of podocyte processes/ fusion of podocytes
