Acute kidney injury in dogs: Etiology, clinical and clinicopathologic findings, prognostic markers, and outcome

Abstract

Background: Acute kidney injury (AKI) is a common, potentially fatal condition.

Objectives: To characterize the etiologies, clinical and clinicopathologic findings, hospitalization period, and outcome of dogs with AKI and to identify markers of negative prognosis.

Animals: Two hundred forty-nine client-own dogs diagnosed with AKI and hospitalized at a veterinary teaching hospital.

Methods: Retrospective study. Search of medical records for dogs with AKI.

Results: Common clinical signs included lethargy (225/249, 90%), anorexia (206/249, 83%), and vomiting (168/249, 68%). Etiologies included ischemic/inflammatory (144/249, 58%), infectious (19/249, 8%), nephrotoxicosis (14/249, 6%), or other (13/249, 5%). Hospital-acquired AKI was diagnosed in 9% (23/249) of the dogs. Median presentation and peak serum creatinine (sCr) concentrations were 4 mg/dL (range, 1.1-37.9) and 4.6 mg/dL (range, 1.1-43.1), respectively. Dogs were classified to AKI grades as follows: Grade I, 6 (2%), Grade II, 38 (15%), Grade III, 89 (36%), Grade IV, 77 (31%), and Grade V, 39 (16%). One hundred and sixty-four (66%) dogs survived. There was a positive association between death and AKI grade (P = .009). The case fatality rate was higher among dogs with anuria compared with dogs without anuria (50% vs 28%, respectively; odds ratio [95% confidence interval]: 2.5 [1.39-4.6]; P = .002). Forty-seven (18.8%) dogs underwent hemodialysis, of which 60% survived.

Conclusion and clinical importance: Two-thirds of dogs with AKI survived. Hospital-acquired AKI was common. The severity of AKI, as reflected by presence of anuria, AKI grade, and other body organs involvement, was associated with the outcome.

Keywords: AKI; azotemia; outcome; renal failure; uremia.