Acute Kidney Injury in Adults: An Underdiagnosed Condition

Kristy Washinger; MSN; FNP-BC


Journal for Nurse Practitioners. 2017;13(10):667-674. 

In This Article

Definition and Stages

In 2012, the Kidney Disease Improving Global Outcomes (KDIGO) international committee created clinical practice guidelines for AKI because of the increase in incidence and complications of AKI. AKI is now replacing terms such as acute renal failure or acute renal insufficiency to help clarify and standardize the diagnosis.[4] AKI results in the inability of the body to maintain acid-base, fluid, and electrolyte balance.

The KDIGO defines AKI as an increase in serum creatinine ≥ 0.3 mg/dL within 48 hours, an increase in serum creatinine ≥ 1.5 times a known baseline level or presumed to have occurred within the prior 7 days, or a urine volume < 0.5 mL/kg/h for 6 hours.[5]

The KDIGO AKI guideline is the current guideline on the staging of AKI (Table 1), and it builds on 2 previous guidelines: Risk, Injury, Failure, Loss of Kidney Function, and End-Stage Kidney Disease classification and the Acute Kidney Injury Network guideline.[6] The full KDIGO AKI guideline can be found at The KDIGO AKI guideline is easy to use in a variety of settings but has limitations. These limitations include 1) the presumptive presence of a baseline creatinine value before the insult and 2) a decrease in urine output. These markers manifest relatively late after injury has occurred and do not consider the nature or site of the kidney injury.