Neonatal kidney injury: diagnosis, management, and long-term kidney health – the perspective of the European Neonatal Nephrology Working Group

Advances in perinatal and neonatal care have improved the survival of preterm and intrauterine growth-restricted (IUGR) infants, yet these achievements bring underlit challenges, including kidney development and long-term renal health. Because nephrogenesis occurs largely before birth, preterm birth interrupts this process, resulting in reduced and structurally immature nephrons. These infants, as well as those exposed to adverse intrauterine environments such as malnutrition or preeclampsia, are predisposed to kidney vulnerability that extends into later life, increasing their risk for chronic kidney disease (CKD). Paediatric nephrologists and neonatologists from the Neonatal Nephrology Working Group (WG) of the European Society for Paediatric Nephrology (ESPN) and the Special Interest Group of the European Society for Paediatric Research (ESPR) collaborated to synthesize current evidence on risk factors, mechanisms, and management of kidney injury in neonates. Key findings highlight that neonatal acute kidney injury (AKI) remains difficult to diagnose using adult-derived criteria, as creatinine-based definitions fail to account for postnatal adaptation and fluid dynamics. AKI in neonates commonly arises from multifactorial causes (i.e., perinatal asphyxia, sepsis, patent ductus arteriosus, and/or exposure to nephrotoxic drugs) and often manifests through systemic consequences like fluid overload. Management emphasizes fluid and electrolyte optimization, cautious use of nephrotoxic agents, and individualized nutrition to support growth while minimizing metabolic derangements. Emerging neonatal-specific kidney replacement therapy technologies, including miniaturized and continuous circuits, expand therapeutic options but require further evaluation. Follow-up is warranted; nevertheless, current evidence is unable to provide an evidence-based strategy. This evaluation underscores the urgent need for integrative research, neonatal-specific diagnostic criteria, and evidence-based guidelines tailored to this vulnerable population. By bridging neonatology and nephrology, the newly established WG aims to foster multidisciplinary strategies that improve both short- and long-term kidney outcomes in preterm and critically ill newborns. A higher resolution version of the Graphical abstract is available as Supplementary information