Acute kidney injury (AKI) has been shown to be a predictor of mortality in human medicine. Published studies in the veterinary literature evaluating relative changes in serum creatinine concentration as a prognostic factor are limited.
To evaluate an AKI grading system based on serum creatinine concentration to determine if it correlates with outcome prediction in dogs and cats.
Six hundred forty-five dogs and 209 cats that had at least 2 serum creatinine concentration measurements measured within 7 days.
Retrospective study. Dogs and cats with an initial serum creatinine concentrations of ≤1.6 mg/dL and that had more than 1 concentration measured within 2, 3, and 7 days were placed into levels (0–2) based on absolute changes. Mortality then was determined at 30 and 90 days.
Based on odds ratios calculated with a 95% confidence interval, dogs placed in level 1 within 2 days were approximately 3 times more likely to die within 90 days. Dogs placed in level 2 within 2, 3, or 7 days were approximately 3 times more likely to die within 30 or 90 days. Cats placed in level 2 within 3 or 7 days were approximately 3 times more likely to die at 30 days and 4 times more likely to die if placed in this level within 7 days. If placed in level 2 within 2 or 3 days, cats were approximately 3 times more likely to die within 90 days.
Conclusions and Clinical Importance
Detecting increasing severity of azotemia helps predict mortality in dogs and cats.