Acute Kidney Injury (AKI) Differential Diagnoses

Updated: Jun 10, 2022
  • Author: Biruh T Workeneh, MD, PhD, FASN; Chief Editor: Vecihi Batuman, MD, FASN  more...
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Diagnostic Considerations

Although acute kidney injury (AKI) is a potentially reversible condition, it can occur in patients with chronic renal failure. Every effort should be made to identify reversibility, even if improvement in renal function is marginal. The best way to identify reversibility is by tracking the rate of deterioration of renal function. If there is an acceleration of the rate at which the patient’s renal function is worsening, the cause should be sought and treated.

Differentials to consider in AKI include the following:

  • Abdominal aneurysm
  • Alcohol toxicity
  • Alcoholic ketoacidosis
  • Chronic renal failure
  • Dehydration
  • Diabetic ketoacidosis
  • Gastrointestinal (GI) bleeding
  • Heart failure
  • Metabolic acidosis
  • Obstructive uropathy
  • Protein overloading
  • Renal calculi
  • Sickle cell anemia
  • Steroid use
  • Urinary obstruction
  • Urinary tract infection

Urine output in differential diagnosis

Changes in urine output generally correlate poorly with changes in the glomerular filtration rate (GFR). Approximately 50-60% of all causes of AKI are nonoliguric. However, the identification of anuria, oliguria, and nonoliguria may be useful in the differential diagnosis of AKI, as follows:

  • Anuria (< 100 mL/day) - Urinary tract obstruction, renal artery obstruction, rapidly progressive glomerulonephritis, bilateral diffuse renal cortical necrosis

  • Oliguria (100-400 mL/day) - Prerenal failure, hepatorenal syndrome

  • Nonoliguria (>400 mL/day) - Acute interstitial nephritis, acute glomerulonephritis, partial obstructive nephropathy, nephrotoxic and ischemic ATN, radiocontrast-induced AKI, and rhabdomyolysis

Differential Diagnoses