DR Medhat MRCP

Acute renal failure (now termed acute kidney injury `AKI`)
Def : abrupt loss of renal function i.e any one of the following :
Causes :
Increase in SCr by ≥ 0.3 mg/dl ( ≥ 26.5 µmol/l) within 48 hours; or
Increase in SCr to ≥ 1.5 times baseline, which is known or presumed to
have occurred within the prior 7 days; or
Urine volume < 0.5 ml/kg/h for 6 hours .
Prerenal:
o Volume depletion ( hge, severe vomiting or diarrhoea, burns,over diuresis)
o Oedematous states : cardiac failure, cirrhosis, nephrotic syndrome
o Hypotension (eg cardiogenic shock, sepsis, anaphylaxis)
o Cardiovascular (eg severe cardiac failure, arrhythmias)
o Renal hypoperfusion : (NSAIDs) or (anti COX-2) , (ACE) inhibitors or ARB, AAA,
RAS, hepatorenal syndrome
Intrinsic acute kidney injury (AKI):
o Glomerular disease : GN, thrombosis, HUS.
o Tubular injury: (ATN) Ischaemic : prolonged renal ischemia
Nephrotoxins (eg aminoglycosides, radiocontrast
media,myoglobin, cisplatin, heavy metals, light chains in MM)
o Acute interstitial nephritis due to drugs (eg NSAIDs) or infection
o Vascular disease ( vasculitis (usually associated with antineutrophil
cytoplasmic antibody), cryoglobulinaemia, polyarteritis nodosa, thrombotic
microangiopathy, cholesterol emboli, renal artery stenosis, renal vein
thrombosis, malignant hypertension
o Eclampsia
Postrenal:
o Calculus
o Blood clot
o Papillary necrosis
o Urethral stricture
o Prostatic hypertrophy or malignancy
o Bladder tumour
o Radiation fibrosis
o Pelvic malignancy
o Retroperitoneal fibrosis
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