Acute tubular necrosis
Acute tubular necrosis (ATN) describes an intrarenal form of acute kidney injury in which the tubules become damaged and dysfunctional, due to hypoperfusion and/or nephrotoxins.
- Accounts for the majority of intrinsic acute kidney injury cases.
- Depending on the severity, may be asymptomatic, but in severe cases, presents with initial oliguria with azotemia and uremia (lasting 1-3 weeks), followed by diuretic phase (increased diuresis, due to fluid overload).
- When comparing ATN to prerenal AKI:
- Prerenal AKI appears with a much higher BUN/creatinine ratio (>20)
- ATN appears with low osmolality (<350) and high urine sodium (>40)
- Oliguria in prerenal AKI can be corrected with fluid resuscitation, but in ATN it cannot be.
Etiology and pathophysiology
- The tubular cells are highly