Kidney injury biomarkers 5?years after AKI due to pediatric cardiac surgery

摘要

Background We previously reported that children undergoing cardiac surgery are at high risk for long-term chronic kidney disease (CKD) and hypertension, although postoperative acute kidney injury (AKI) is not a risk factor for worse long-term kidney outcomes. We report here our evaluation of renal injury biomarkers 5?years after cardiac surgery to determine whether they are associated with postoperative AKI or long-term CKD and hypertension. Methods Children aged 1?month to 18?years old undergoing cardiopulmonary bypass were recruited to this prospective cohort study. At 5?years after cardiac surgery, we measured urine interleukin-18, kidney injury molecule-1, monocyte chemoattractant protein-1, YKL-40, and neutrophil gelatinase–associated lipocalin (NGAL). Biomarker levels were compared between patients with AKI and those without. We also performed a cross-sectional analysis of the association between these biomarkers with CKD and hypertension. Results Of the 305 subjects who survived hospitalization, four (1.3%) died after discharge, and 110 (36%) participated in the 5-year follow-up. Of these 110 patients, 49 (45%) had AKI. Patients with versus those without postoperative AKI did not have significantly different biomarker concentrations at 5?years after cardiac surgery. None of the biomarker concentrations were associated with CKD or hypertension at 5 years of follow-up, although CKD and hypertension were associated with a higher proportion of participants with abnormal NGAL levels. Conclusions Postoperative pediatric AKI is not associated with urinary kidney injury biomarkers 5?years after surgery. This may represent a lack of chronic renal injury after AKI, imprecise estimation of the glomerular filtration rate, the need for longer follow-up to detect chronic renal damage, or that our studied biomarkers are inadequate for evaluating subclinical chronic renal injury.