# AKI Evaluation: Mechanism Before a Label

Document kidney recovery, persistent dysfunction, and discharge follow-up. AKI increases subsequent kidney risk even when creatinine appears to return toward baseline.

![Infographic: AKI Evaluation: Mechanism Before a Label](https://urinenephrology.org/visual-reference/images/mastery-aki-evaluation.png?v=20261003c)

## Recognize AKI with published criteria

KDIGO 2012 defines AKI by creatinine rising ≥0.3 mg/dL within 48 hours, ≥1.5 times baseline within 7 days, or urine output <0.5 mL/kg/hour for 6 hours. Compare with a credible baseline and apply the worst qualifying creatinine or urine-output stage.

## Stabilize threats

Hyperkalemia, pulmonary edema, severe acidemia, uremic complications, and obstruction can require urgent action before the full diagnosis is available.

## Localize systematically

Review perfusion, congestion, medications, infection, recent procedures, urinalysis, protein excretion, and urinary tract imaging when indicated.

## Reassess interventions

Treat reversible causes, adjust drug dosing, and balance fluid needs against congestion. Repeated assessment is more useful than a one-time prerenal/intrinsic label.

## Distinguish draft from published criteria

The KDIGO 2026 AKI/AKD update remains a public-review draft. Proposed biomarker-enhanced staging must be distinguished from published AKI criteria; reassess recommendations when final guidance becomes available.

## Separate stage from cause

Rhabdomyolysis can cause true severe AKI; pigment injury does not exempt a patient from KDIGO staging. Increased creatinine generation may complicate interpretation, so assess urine output, trends, potassium, perfusion, and sediment. Stage describes dysfunction; it does not identify histology or independently dictate dialysis.

## Supporting evidence

- [Supporting guideline or source](https://kdigo.org/wp-content/uploads/2016/10/KDIGO-2012-AKI-Guideline-English.pdf)

## Source lessons

- [aki evaluation](https://urinenephrology.org/mastery/aki-advanced/aki-evaluation.html)
- [aki staging 2012 vs 2026 bridge](https://urinenephrology.org/mastery/aki-advanced/aki-staging-2012-vs-2026-bridge.html)

Read alongside the full lessons; the findings and decisions shown here require the stated clinical context.