Nephron loss detected by MRI following neonatal acute kidney injury in rabbits.
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ABSTRACT:
SUBMITTER: Charlton JR
PROVIDER: S-EPMC7255918 | biostudies-literature | 2020 Jun
REPOSITORIES: biostudies-literature
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Nephron loss detected by MRI following neonatal acute kidney injury in rabbits.
Charlton Jennifer R JR Baldelomar Edwin J EJ deRonde Kimberly A KA Cathro Helen P HP Charlton Nathan P NP Criswell Stacey J SJ Hyatt Dylan M DM Nam Sejin S Pearl Valeria V Bennett Kevin M KM
Pediatric research 20191205 7
<h4>Background</h4>Acute kidney injury affects nearly 30% of preterm neonates in the intensive care unit. We aimed to determine whether nephrotoxin-induced AKI disrupted renal development assessed by imaging (CFE-MRI).<h4>Methods</h4>Neonatal New Zealand rabbits received indomethacin and gentamicin (AKI) or saline (control) for four days followed by cationic ferritin (CF) at six weeks. Ex vivo images were acquired using a gradient echo pulse sequence on 7 T MRI. Glomerular number (N<sub>glom</su ...[more]
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Project description:BackgroundAcute kidney injury (AKI) is common in the kidney transplant population.ObjectiveTo derive a multivariable survival model that predicts time to graft loss following AKI.DesignRetrospective cohort study using health care administrative and laboratory databases.SettingSouthwestern Ontario (1999-2013) and Ottawa, Ontario, Canada (1996-2013).PatientsWe included first-time kidney only transplant recipients who had a hospitalization with AKI 6 months or greater following transplant.MeasurementsAKI was defined using the Acute Kidney Injury Network criteria (stage 1 or greater). The first episode of AKI was included in the analysis. Graft loss was defined by return to dialysis or repeat kidney transplant.MethodsWe performed a competing risk survival regression analysis using the Fine and Gray method and modified the model into a simple point system. Graft loss with death as a competing event was the primary outcome of interest.ResultsA total of 315 kidney transplant recipients who had a hospitalization with AKI 6 months or greater following transplant were included. The median (interquartile range) follow-up time was 6.7 (3.3-10.3) years. Graft loss occurred in 27.6% of the cohort. The final model included 6 variables associated with an increased risk of graft loss: younger age, increased severity of AKI, failure to recover from AKI, lower baseline estimated glomerular filtration rate, increased time from kidney transplant to AKI admission, and receipt of a kidney from a deceased donor. The risk score had a concordance probability of 0.75 (95% confidence interval [CI], 0.69-0.82). The predicted 5-year risk of graft loss fell within the 95% CI of the observed risk more than 95% of the time.LimitationsThe CIs of the estimates were wide, and model overfitting is possible due to the limited sample size; the risk score requires validation to determine its clinical utility.ConclusionsOur prognostic risk score uses commonly available information to predict the risk of graft loss in kidney transplant patients hospitalized with AKI. If validated, this predictive model will allow clinicians to identify high-risk patients who may benefit from closer follow-up or targeted enrollment in future intervention trials designed to improve outcomes.
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Project description:BackgroundAcute kidney injury (AKI) is associated with a dismal prognosis in Transcatheter Aortic Valve replacement (TAVR). Acute kidney recovery (AKR), a phenomenon reverse to AKI has recently been associated with better outcomes.MethodsBetween November 2012 to May 2018, we explored consecutive patients referred to our Heart Valve Center for TAVR. AKI was defined according to the VARC-2 definition. Mirroring the VARC-2 definition of AKI, AKR was defined as a decrease in serum creatinine (≥50%) or ≥25% improvement in GFR up to 72 hours after TAVR.ResultsAKI and AKR were respectively observed in 8.3 and 15.7% of the 574 patients included. AKI and AKR patients were associated to more advanced kidney disease at baseline. At a median follow-up of 608 days (range 355-893), AKI and AKR patients experienced an increased cardiovascular mortality compared to unchanged renal function patients (14.6% and 17.8% respectively, vs. 8.1%, CI 95%, p<0.022). Chronic kidney disease, (HR: 3.9; 95% CI 1.7-9.2; p < 0.001) was the strongest independent factor associated with AKI similarly to baseline creatinine level (HR: 1; 95% CI 1 to 1.1 p < 0.001) for AKR. 72-hours post procedural AKR (HR: 2.26; 95% CI 1.14 to 4.88; p = 0.021) was the strongest independent predictor of CV mortality.ConclusionsBoth AKR and AKI negatively impact long term clinical outcomes of patients undergoing TAVR.
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