Prospective evaluation of novel biomarkers of acute kidney injury in dogs following cardiac surgery under cardiopulmonary bypass

OBJECTIVE: To assess the occurrence of acute kidney injury (AKI) in dogs undergoing cardiac surgery under cardiopulmonary bypass (CPB) and explore associations between traditional and novel serum and urinary biomarkers. DESIGN: Prospective cohort study conducted between July 2018 and April 2019. SETTING: University teaching hospital. ANIMALS: Nineteen dogs undergoing cardiac surgery under CPB with preoperative serum creatinine <140 μmol/L (<1.6 mg/dl). INTERVENTIONS: Blood and urine samples were obtained at 4 time points: preoperatively following general anesthesia induction, immediately postoperatively, and 2 and 4 days postoperatively (T(1), T(2), T(3), and T(4)). AKI was defined as an increase in serum creatinine ≥26.4 μmol/L (≥0.3 mg/dl) above baseline within 48 hours. Serum creatinine, C‐reactive protein (CRP), symmetric dimethylarginine (SDMA), inosine, beta‐aminoisobutyric acid (BAIB), urinary clusterin (uClus), and urinary cystatin B (uCysB) were measured. Data were log‐transformed (log(10)) when appropriate and assessed using linear mixed‐effects models. MEASUREMENTS AND MAIN RESULTS: AKI occurred in 3 of 19 dogs (15.8%, 95% confidence interval: 0.047–0.384). Inosine increased at T(2) (adjusted mean ± standard error: 53 ± 5.6) in all dogs, and then gradually decreased. Log(10)uCysB increased at T(2) (2.3 ± 0.1) in all dogs and remained high. Log(10)CRP and log(10)uClus increased significantly at T(3) (1.9 ± 0.1 and 3.6 ± 0.1, respectively) in all dogs and remained increased. There was a significant positive association between serum creatinine and SDMA (P < 0.001, estimate ± standard error: 0.06 ± 0.00), between log(10)CRP and log(10)uClus (P < 0.001, 0.35 ± 0.08), between SDMA and creatinine as well as between SDMA and BAIB (P < 0.001, 11.1 ± 0.83 and P < 0.001, 1.06 ± 0.22, respectively) for all dogs at all time points. CONCLUSIONS: Inosine and uCysB concentrations changed in all dogs immediately following a surgery under CPB and may indicate tubular injury. Further studies are required to ascertain the usefulness of those biomarkers in early detection of AKI

Prognostic importance of plasma total magnesium in a cohort of cats with azotemic chronic kidney disease

BACKGROUND: Hypomagnesemia is associated with increased mortality and renal function decline in humans with chronic kidney disease (CKD). Magnesium is furthermore inversely associated with fibroblast growth factor 23 (FGF23), an important prognostic factor in CKD in cats. However, the prognostic significance of plasma magnesium in cats with CKD is unknown. OBJECTIVES: To explore associations of plasma total magnesium concentration (tMg) with plasma FGF23 concentration, all-cause mortality, and disease progression in cats with azotemic CKD. ANIMALS: Records of 174 client-owned cats with IRIS stage 2-4 CKD. METHODS: Cohort study. Cats with azotemic CKD were identified from the records of two London-based first opinion practices (1999-2013). Possible associations of baseline plasma tMg with FGF23 concentration and risks of death and progression were explored using, respectively, linear, Cox, and logistic regression. RESULTS: Plasma tMg (reference interval, 1.73-2.57 mg/dL) was inversely associated with plasma FGF23 when controlling for plasma creatinine and phosphate concentrations (partial correlation coefficient, -0.50; P < .001). Hypomagnesemia was observed in 12% (20/174) of cats, and independently associated with increased risk of death (adjusted hazard ratio, 2.74; 95% confidence interval [CI], 1.35-5.55; P = .005). The unadjusted associations of hypermagnesemia (prevalence, 6%; 11/174 cats) with survival (hazard ratio, 2.88; 95% CI, 1.54-5.38; P = .001), and hypomagnesemia with progressive CKD (odds ratio, 17.7; 95% CI, 2.04-154; P = .009) lost significance in multivariable analysis. CONCLUSIONS AND CLINICAL IMPORTANCE: Hypomagnesemia was associated with higher plasma FGF23 concentrations and increased risk of death. Measurement of plasma tMg augments prognostic information in cats with CKD, but whether these observations are associations or causations warrants further investigation

Ionized hypercalcemia in cats with azotemic chronic kidney disease (2012‐2018)

Abstract Background Hypercalcemia is associated with chronic kidney disease (CKD) in cats, but studies assessing the physiologically relevant ionized calcium fraction are lacking. Objectives To describe the prevalence and incidence rate of ionized hypercalcemia, and to explore predictor variables to identify cats at risk of ionized hypercalcemia in a cohort of cats diagnosed with azotemic CKD. Animals One hundred sixty‐four client‐owned cats with azotemic CKD. Methods Variables independently associated with ionized hypercalcemia at diagnosis of azotemic CKD were explored by binary logistic regression. Cats that were normocalcemic at diagnosis of azotemic CKD were followed over a 12‐month period or until ionized hypercalcemia occurred and baseline predictor variables for ionized hypercalcemia explored using Cox proportional hazards and receiver operating characteristic curve analysis. Results Ionized hypercalcemia (median, 1.41 mmol/L; range, 1.38‐1.68) was observed in 33/164 (20%) cats at diagnosis of azotemic CKD and was associated with male sex, higher plasma total calcium and potassium concentrations, and lower plasma parathyroid hormone concentrations. Twenty‐five of 96 initially normocalcemic (26%) cats followed for minimum 90 days developed ionized hypercalcemia (median, 1.46 mmol/L; range, 1.38‐1.80) at a median of 140 days after diagnosis of azotemic CKD (incidence rate, 0.48 per feline patient‐year). Only body condition score was independently associated with incident ionized hypercalcemia. Conclusions and Clinical Importance The occurrence of ionized hypercalcemia is high in cats with CKD. Continued monitoring of blood ionized calcium concentrations is advised

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<p>Blood pressure evaluation form</p

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<p>French version of the guidelines</p