Recovery From Acute Kidney Injury and CKD Following Heart Transplantation in Children, Adolescents, and Young Adults: A Retrospective Cohort Study

Background Acute kidney injury (AKI) is common in children following surgery for congenital heart disease and has been associated with poor long-term kidney outcomes. Children undergoing heart transplantation may be at increased risk for the development of both AKI and chronic kidney disease (CKD). This study examines AKI rates in children, adolescents, and young adults after heart transplantation and analyzes the relationship between AKI and CKD in this population. Study Design Retrospective cohort study. Setting & Participants 88 young patients who underwent heart transplantation at Lucile Packard Children’s Hospital, Stanford, CA, September 1, 2007, to November 30, 2013. Predictor The primary independent variable was AKI within the first 7 postoperative days, ascertained according to the KDIGO (Kidney Disease: Improving Global Outcomes) creatinine criteria (increase in serum creatinine ≥ 1.5 times baseline within 7 days). Outcomes Recovery from AKI at 3 months, ascertained as serum creatinine level < 1.5 times baseline; and development of CKD at 6 and 12 months, ascertained as estimated glomerular filtration rate < 60 mL/min/1.73 m2 for more than 3 months. Results 63 (72%) patients developed AKI; 57% had moderate (stage 2 or severe stage 3) disease. Recovery occurred in 39 of 63 (62%), 50% for stage 2 or 3 versus 78% for stage 1 (P = 0.04). At 6 and 12 months, 3 of 82 (4%) and 4 of 76 (5%) developed CKD, respectively. At both time points, CKD was more common in those without recovery (3/22 [14%] vs 0/38 (0%); P = 0.04, and 3/17 (18%) vs (0/34) 0%; P = 0.03, respectively). Limitations Retrospective design, small sample size, and single-center nature of the study. Conclusions AKI is common after heart transplantation in children, adolescents, and young adults. Nonrecovery from AKI is more common in patients with more severe AKI and is associated with the development of CKD during the first year. Acute kidney injury (AKI) is common in children following surgery for congenital heart disease and has been associated with poor long-term kidney outcomes. Children undergoing heart transplantation may be at increased risk for the development of both AKI and chronic kidney disease (CKD). This study examines AKI rates in children, adolescents, and young adults after heart transplantation and analyzes the relationship between AKI and CKD in this population. Retrospective cohort study. 88 young patients who underwent heart transplantation at Lucile Packard Children’s Hospital, Stanford, CA, September 1, 2007, to November 30, 2013. The primary independent variable was AKI within the first 7 postoperative days, ascertained according to the KDIGO (Kidney Disease: Improving Global Outcomes) creatinine criteria (increase in serum creatinine ≥ 1.5 times baseline within 7 days). Recovery from AKI at 3 months, ascertained as serum creatinine level < 1.5 times baseline; and development of CKD at 6 and 12 months, ascertained as estimated glomerular filtration rate < 60 mL/min/1.73 m2 for more than 3 months. 63 (72%) patients developed AKI; 57% had moderate (stage 2 or severe stage 3) disease. Recovery occurred in 39 of 63 (62%), 50% for stage 2 or 3 versus 78% for stage 1 (P = 0.04). At 6 and 12 months, 3 of 82 (4%) and 4 of 76 (5%) developed CKD, respectively. At both time points, CKD was more common in those without recovery (3/22 [14%] vs 0/38 (0%); P = 0.04, and 3/17 (18%) vs (0/34) 0%; P = 0.03, respectively). Retrospective design, small sample size, and single-center nature of the study. AKI is common after heart transplantation in children, adolescents, and young adults. Nonrecovery from AKI is more common in patients with more severe AKI and is associated with the development of CKD during the first year.