Neonatal Acute Kidney Injury

Abstract

In recent years, there have been significant advancements in our understanding of acute kidney injury (AKI) and its impact on outcomes across medicine. Research based on single-center cohorts suggests that neonatal AKI is very common and associated with poor outcomes. In this state-of-the-art review on neonatal AKI, we highlight the unique aspects of neonatal renal physiology, definition, risk factors, epidemiology, outcomes, evaluation, and management of AKI in neonates. The changes in renal function with gestational and chronologic age are described. We put forth and describe the neonatal modified Kidney Diseases: Improving Global Outcomes AKI criteria and provide the rationale for its use as the standardized definition of neonatal AKI. We discuss risk factors for neonatal AKI and suggest which patient populations may warrant closer surveillance, including neonates ,1500 g, infants who experience perinatal asphyxia, near term/ term infants with low Apgar scores, those treated with extracorporeal membrane oxygenation, and those requiring cardiac surgery. We provide recommendations for the evaluation and treatment of these patients, including medications and renal replacement therapies. We discuss the need for long-term follow-up of neonates with AKI to identify those children who will go on to develop chronic kidney disease. This review highlights the deficits in our understanding of neonatal AKI that require further investigation. In an effort to begin to address these needs, the Neonatal Kidney Collaborative was formed in 2014 with the goal of better understanding neonatal AKI, beginning to answer critical questions, and improving outcomes in these vulnerable populations.

Acute Kidney Injury Urine Biomarkers in Very Low-Birth-Weight Infants

“…SCr was measured once in four of 113 (3.5%), twice in six of 113 (5.3%), three times in ten of 113 (8.8%), and at least four times in 93 of 113 (82%) of the cohort during the 2 weeks of life (median, 5 [range, [1][2][3][4][5][6][7][8][9][10][11][12][13][14] days). Neonatal AKI was defined using the Kidney Disease Improving Global Outcomes AKI definition, in which stage 1 was defined as an increase of SCr $ 0.3 mg/dl or Figure 1.…”

“…AKI in premature infants is common and predicts poor clinical outcomes (1). Current identification of AKI relies on acute elevation of serum creatinine (SCr), but SCr-based definitions are hampered by numerous problems: most important, that SCr is a measure of function, not damage (2).…”

The Impact of Kidney Development on the Life Course: A Consensus Document for Action

“…AKI occurs in 16-70% of neonatal populations [136,137,138]. Some of this variability comes from reports of neonates and preterm infants with varying comorbidities (e.g., congenital diaphragmatic hernia, cardiac surgery, and asphyxia) but also reflects the challenge of diagnosing AKI in the neonate and the lack, until recently, of a uniform diagnostic classification [136].…”

Clinical Utility of Rapid Plasma Neutrophil Gelatinase-Associated Lipocalin Assays for Diagnosing Acute Kidney Injury in Critically Ill Newborn Infants

“…Further investigations with larger patient groups are also required to better assess the role of rapid plasma NGAL assay for AKI diagnosis in critically ill newborn infants at bedside. Third, to verify a better biomarker for AKI, simultaneous examination of other serum bio markers is desirable 24,32) . Recent studies have unveiled other AKI biomarkers including interleukin-18 14) and cystatin C 15) .…”

“…The diagnosis of AKI was based on serum Cr ≥1.5 mg/dL on the first week of life (normal renal function in the mother of the neonate) or on the neonatal modified Kidney Disease: Improving Global Outcome (KDIGO) Cr criteria during the first week of life 7,23,24) . The neonatal modified KDIGO Cr criteria are as follows:…”