Fig. 1: A tiered approach to incorporating short- and long-term kidney outcomes into neonatal studies.

This approach attempts to balance the costs associated with ascertainment of AKI and CKD with the knowledge gained. We have stratified studies into four categories with the short-term outcome of acute kidney injury and the long-term outcome being chronic kidney disease or hypertension. We have outlined our recommendations in the same color as the study and highlight the ideal or optimal extra studies in orange boxes. High risk events include, but are not limited to, acquired neonatal intestinal disease (necrotizing enterocolitis (NEC) and spontaneous intestinal perforation), hemodynamically significant patent ductus arteriosus (PDA), sepsis, shock, surgery, and exposure to multiple nephrotoxic medications. Definitions: HRE high risk event, sCr serum creatinine, UOP urine output.