Serum NGAL and copeptin levels as predictors of acute kidney injury in asphyxiated neonates

Artificial intelligence in early detection and prediction of pediatric/neonatal acute kidney injury: current status and future directions

Acute kidney injury (AKI) has a significant impact on the short-term and long-term clinical outcomes of pediatric and neonatal patients, and it is imperative in these populations to mitigate the pathways leading to AKI and be prepared for early diagnosis and treatment intervention of established AKI. Recently, artificial intelligence (AI) has provided more advent predictive models for early detection/prediction of AKI utilizing machine learning (ML). By providing strong detail and evidence from risk scores and electronic alerts, this review outlines a comprehensive and holistic insight into the current state of AI in AKI in pediatric/neonatal patients. In the pediatric population, AI models including XGBoost, logistic regression, support vector machines, decision trees, naïve Bayes, and risk stratification scores (Renal Angina Index (RAI), Nephrotoxic Injury Negated by Just-in-time Action (NINJA)) have shown success in predicting AKI using variables like serum creatinine, urine output, and electronic health record (EHR) alerts. Similarly, in the neonatal population, using the "Baby NINJA" model showed a decrease in nephrotoxic medication exposure by 42%, the rate of AKI by 78%, and the number of days with AKI by 68%. Furthermore, the "STARZ" risk stratification AI model showed a predictive ability of AKI within 7 days of NICU admission of AUC 0.93 and AUC of 0.96 in the validation and derivation cohorts, respectively. Many studies have reported the superiority of using biomarkers to predict AKI in pediatric patients and neonates as well. Future directions include the application of AI along with biomarkers (NGAL, CysC, OPN, IL-18, B2M, etc.) in a Labelbox configuration to create a more robust and accurate model for predicting and detecting pediatric/neonatal AKI.

Iron homeostasis and post-hemorrhagic hydrocephalus: a review

Iron physiology is regulated by a complex interplay of extracellular transport systems, coordinated transcriptional responses, and iron efflux mechanisms. Dysregulation of iron metabolism can result in defects in myelination, neurotransmitter synthesis, and neuronal maturation. In neonates, germinal matrix-intraventricular hemorrhage (GMH-IVH) causes iron overload as a result of blood breakdown in the ventricles and brain parenchyma which can lead to post-hemorrhagic hydrocephalus (PHH). However, the precise mechanisms by which GMH-IVH results in PHH remain elusive. Understanding the molecular determinants of iron homeostasis in the developing brain may lead to improved therapies. This manuscript reviews the various roles iron has in brain development, characterizes our understanding of iron transport in the developing brain, and describes potential mechanisms by which iron overload may cause PHH and brain injury. We also review novel preclinical treatments for IVH that specifically target iron. Understanding iron handling within the brain and central nervous system may provide a basis for preventative, targeted treatments for iron-mediated pathogenesis of GMH-IVH and PHH.

Predictive ability of 2-h serum neutrophil gelatinase-associated lipocalin for perinatal asphyxia-induced acute kidney injury

BACKGROUND

Acute kidney injury (AKI) is a common cause of mortality and morbidity in asphyxiated newborns. Recent research suggests serum neutrophil gelatinase-associated lipocalin (sNGAL) as an early biomarker of AKI in newborns with perinatal asphyxia. The prospect of sNGAL is yet to be studied in Nigeria, with a huge burden of asphyxia-related neonatal deaths.

METHODS

A cross-sectional analytic study was conducted on 53 asphyxiated term newborns and 53 healthy babies at the newborn unit of the Wesley Guild Hospital Ilesa, Nigeria. sNGAL was assessed in all neonates with perinatal asphyxia at baseline (within 30 min of delivery), 2 h, and 48 h of life.

RESULTS

Mean sNGAL was significantly higher in asphyxiated newborns than in the control group, 81.4 (45.9) vs. 53.7 (29.2), p < 0.001. However, the mean 2-h sNGAL levels were similar in asphyxiated babies with and without AKI 100.5 (36.7) ng/ml vs. 85.3 (31.4) ng/ml, p = 0.115. The 2-h sNGAL with an AUC of 0.61 at an 83.0 ng/ml cut-off had an acceptable discriminating capability of predicting AKI. The sensitivity, specificity, positive predictive value, and negative predictive value were 80%, 51.5%, 50%, and 81%, respectively.

CONCLUSION

This study shows that sNGAL levels were significantly elevated in newborns with perinatal asphyxia compared to healthy neonates, but the 2-h sNGAL is less predictive of AKI in newborns with perinatal asphyxia. The negative predictive value is high, and this may find some relevance in the attempts at early exclusion of asphyxiated babies prone to AKI. A higher resolution version of the Graphical abstract is available as Supplementary information.

Potential Adjuncts to Therapeutic Hypothermia to Mitigate Multiorgan Injury in Perinatal Hypoxia-Ischemia

Over the last 2 decades, therapeutic hypothermia has become the standard of care to reduce morbidity and mortality in neonates affected by moderate-to-severe hypoxic-ischemic encephalopathy (HIE). There is a significant interest in improving the neurologic outcomes of neonatal HIE, ranging from adjunctive therapy to therapeutic hypothermia. Importantly, the pathophysiologic mechanisms underlying HIE also affect multiple other organs, contributing to high morbidity and mortality in this patient population. This review focuses on the adjunct therapies currently under investigation to mitigate the impact of hypoxic-ischemic injury on the brain, kidneys, liver, heart, and gastrointestinal system.

Gut microbiota and neonatal acute kidney injury biomarkers

One of the most frequent issues in newborns is acute kidney injury (AKI), which can lengthen their hospital stay or potentially raise their chance of dying. The gut-kidney axis establishes a bidirectional interplay between gut microbiota and kidney illness, particularly AKI, and demonstrates the importance of gut microbiota to host health. Since the ability to predict neonatal AKI using blood creatinine and urine output as evaluation parameters is somewhat constrained, a number of interesting biomarkers have been developed. There are few in-depth studies on the relationships between these neonatal AKI indicators and gut microbiota. In order to gain fresh insights into the gut-kidney axis of neonatal AKI, this review is based on the gut-kidney axis and describes relationships between gut microbiota and neonatal AKI biomarkers.

LncRNA NEAT1 accelerates renal fibrosis progression via targeting miR-31 and modulating RhoA/ROCK signal pathway

Renal fibrosis is the final pathway for chronic kidney disease to end-stage renal failure. Noncoding RNAs have been reported to play a crucial role in renal fibrosis. Here, the effects of long noncoding RNA (lncRNA) nuclear-enriched abundant transcript 1 (NEAT1) and miR-31 on renal fibrosis and their regulatory mechanism were evaluated. RT-qPCR was used to assess NEAT1, miR-31, and RhoA levels. Western blot was performed to analyze the expression of fibrosis markers, RhoA, rho-related kinase (ROCK1), and connective tissue growth factor (CTGF). RNA immunoprecipitation (RIP), fluorescence in situ hybridization (FISH), and luciferase reporter assays verified the interaction between miR-31 and NEAT1 or RhoA. Renal fibrosis and injury were observed by Masson and hematoxylin and eosin (H&E) staining. The expression level of inflammatory cytokines was detected by ELISA. Immunohistochemistry (IHC) was performed to examine the expression levels of α-smooth muscle actin (α-SMA) and RhoA in renal tissues. We showed that NEAT1 was highly expressed, whereas miR-31 was decreased in renal fibrosis. NEAT1 was found to directly bind miR-31 to positively regulate RhoA expression. Furthermore, NEAT1 silencing inhibited renal fibrosis and inflammation and suppressed the RhoA/ROCK1 signaling pathway. However, knockdown of miR-31 could reverse these effects. NEAT1 silencing or overexpression of miR-31 alleviated renal fibrosis in vivo. In conclusion, NEAT1 accelerates renal fibrosis progression via negative regulation of miR-31 and the activation of RhoA/ROCK1 pathway, thereby upregulating the expression level of CTGF, providing a theoretical basis for treatment and prognostic evaluation of renal fibrosis.

Predictive value of neutrophil gelatinase-associated lipocalin in children with acute kidney injury: A systematic review and meta-analysis

Purpose

Neutrophil gelatin lipase carrier protein (NGAL) has been used as an early biomarker to predict acute kidney injury (AKI). However, the predictive value of NGAL in urine and blood in children with acute kidney injury in different backgrounds remains unclear. Therefore, we conducted this systematic review and meta-analysis to explore the clinical value of NGAL in predicting AKI in children.

Methods

Computerized databases were searched for relevant the studies published through August 4th, 2022, which included PUBMED, EMBASE, COCHRANE and Web of science. The risk of bias of the original included studies was assessed by using the Quality Assessment of Studies for Diagnostic Accuracy (QUADA-2). At the same time, subgroup analysis of these data was carried out.

Results

Fifty-three studies were included in this meta-analysis, involving 5,049 patients, 1,861 of whom were AKI patients. The sensitivity and specificity of blood NGAL for predicting AKI were 0.79 (95% CI: 0.69-0.86) and 0.85 (95% CI: 0.75-0.91), respectively, and SROC was 0.89 (95% CI: 0.86-0.91). The sensitivity and specificity of urine NGAL for predicting AKI were 0.83 (95% CI: 0.78-0.87) and 0.81 (95% CI: 0.77-0.85), respectively, and SROC was 0.89 (95% CI: 0.86-0.91). Meanwhile, the sensitivity and specificity of overall NGAL (urine and blood NGAL) for predicting AKI in children were 0.82 (95% CI: 0.77-0.86) and 0.82 (95% CI: 0.78-0.86), respectively, and SROC was 0.89 (95% CI: 0.86-0.91).

Conclusion

NGAL is a valuable predictor for AKI in children under different backgrounds. There is no significant difference in the prediction accuracy between urine NGAL and blood NGAL, and there is also no significant difference in different measurement methods of NGAL. Hence, NGAL is a non-invasive option in clinical practice. Based on the current evidence, the accuracy of NGAL measurement is the best at 2 h after cardiopulmonary bypass (CPB) and 24 h after birth in asphyxiated newborns.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier: CRD42022360157.

Effects of aminophylline on the levels of neutrophil gelatinase-associated lipocalin (NGAL) in asphyxiated term neonates

OBJECTIVE

Our study evaluates the effects of aminophylline in the reduction of NGAL levels in perinatal asphyxia.

METHODS

Term neonates with hypoxic ischaemic encephalopathy who were divided into two groups, the treatment and placebo. Urine NGAL levels were measured on day one and four of the treatment using BIOPORTO kits in both the groups.

RESULTS

Day 1 NGAL levels were not statistically different in either group irrespective of the age, gender and the mode of delivery. on 4^th day, NGAL in treatment group significantly decreased as compared to day 1 levels and placebo day-4 levels. significant differences were seen between first and fourth day NGAL levels among children with normal and caesarean birth and among female and male neonates.

CONCLUSIONS

Following the treatment with aminophylline, NGAL levels in asphyxiated neonates are likely to reduce. Further studies based on other kidney dysfunction parameters can lead to the better and accurate conclusions.

Copeptin Concentrations in Plasma of Healthy Neonates in Relation to Water–Electrolyte Homeostasis in the Early Adaptation Period

Copeptin (CTproAVP) is a stable by-product of arginine–vasopressin synthesis and reflects its secretion by the pituitary gland, considered as a potential new marker of dehydration. The objective of the study was to investigate CTproAVP measured after the first 48 h of postnatal life in relation to serum effective osmolality, urine osmolality, and vessels filling according to the following variables: delivery mode, postnatal weight loss, fluids administered intravenously to the mother, and fluids given orally to the neonate. A prospective observational study was conducted with 200 healthy term infants (53% male) enrolled. Serum CTproAVP concentrations were measured using the ELISA kit; haematocrit, urine osmolality, serum effective osmolality were assessed after 48 h of life. Sonographic measurements of inferior vena cava (IVC) and aorta (Ao) were performed and IVC/Ao ratios were calculated. No correlations were found between CTproAVP concentrations and both serum effective osmolality and urine osmolality. There was also no association between CTproAVP concentrations and vessel filling represented by IVC/Ao index at 48 h of life.

Malondialdehyde and Neutrophil Gelatinase-Associated Lipocalin as Markers of Oxidative Stress in Small for Gestational Age Newborns from Hypertensive and Preeclamptic Pregnancies

Introduction. It is speculated that preeclampsia and hypertension during pregnancy are associated with an imbalance of the placental antioxidant defence, which results in the overproduction of reactive oxygen species and fetal growth restriction. Many research implied that oxidant stress in utero may be an important determinant of mortality and morbidity in neonates. Moreover, the authors demonstrated the reduced number of nephrons and a higher prevalence of renal injury in neonates with growth restriction, including small for gestational age (SGA) neonates. Alas, it remains unclear whether basal antioxidant status is altered in the kidneys of SGA newborns. Materials and Methods. In this study, we assessed neutrophil gelatinase-associated lipocalin (NGAL) and malondialdehyde (MDA) levels in samples collected from umbilical blood and 12 hours after delivery in neonates born by mothers suffering from preeclampsia or hypertension during pregnancy and those from physiological pregnancies. Additionally, the authors evaluated levels of the aforementioned biomarkers regarding the occurrence of growth restriction in newborns. For this study, we enrolled 27 newborns, which fulfilled inclusion criteria for SGA diagnosis (SGA group), while 21 were appropriate for gestational age neonates, as the AGA group. Results. In the presented study, we have found significant differences in umbilical cord MDA and NGAL concentration between the SGA and AGA groups. Such dependencies were not found in blood samples from neonates collected in the first 12 hours of life for MDA and NGAL concentrations. Additionally, we have observed differences in umbilical MDA and NGAL levels between newborns of preeclamptic or hypertensive mothers compared to healthy ones. A significant correlation between the occurrence of hypertension during pregnancy and umbilical MDA and NGAL concentrations was also found. Conclusions. Small for gestational age newborns or those born by preeclamptic and hypertensive mothers had significantly higher MDA and NGAL levels as compared to healthy ones. Further investigation is needed to understand the pathophysiologic influence of hypertension in pregnancy and oxidative stress injury in newborns with growth restriction.

Fluid management, electrolytes imbalance and renal management in neonates with neonatal encephalopathy treated with hypothermia

Kidney dysfunction and acute kidney injury (AKI) frequently accompanies neonatal encephalopathy and contributes to neonatal morbidity and mortality. While there are currently no proven therapies for the treatment of AKI, understanding the pathophysiology along with early recognition and treatment of alterations in fluid, electrolyte and metabolic homeostasis that accompany AKI offer opportunity to reduce associated morbidity. Promising new tests and technologies, including urine and serum biomarkers and renal near-infrared spectroscopy offer opportunities to improve diagnosis and monitoring of neonates at risk for kidney injury. Furthermore, recent advances in neonatal kidney supportive therapies such as hemofiltration and hemodialysis may further improve outcomes in this population. This chapter provides an overview of disorders of fluid balance, electrolyte homeostasis and kidney function associated with neonatal encephalopathy and therapeutic hypothermia. Recommendations for fluid and electrolyte management based upon published literature and authors' opinions are provided.

Perinatal Nutritional and Metabolic Pathways: Early Origins of Chronic Lung Diseases

Lung development is not completed at birth, but expands beyond infancy, rendering the lung highly susceptible to injury. Exposure to various influences during a critical window of organ growth can interfere with the finely-tuned process of development and induce pathological processes with aberrant alveolarization and long-term structural and functional sequelae. This concept of developmental origins of chronic disease has been coined as perinatal programming. Some adverse perinatal factors, including prematurity along with respiratory support, are well-recognized to induce bronchopulmonary dysplasia (BPD), a neonatal chronic lung disease that is characterized by arrest of alveolar and microvascular formation as well as lung matrix remodeling. While the pathogenesis of various experimental models focus on oxygen toxicity, mechanical ventilation and inflammation, the role of nutrition before and after birth remain poorly investigated. There is accumulating clinical and experimental evidence that intrauterine growth restriction (IUGR) as a consequence of limited nutritive supply due to placental insufficiency or maternal malnutrition is a major risk factor for BPD and impaired lung function later in life. In contrast, a surplus of nutrition with perinatal maternal obesity, accelerated postnatal weight gain and early childhood obesity is associated with wheezing and adverse clinical course of chronic lung diseases, such as asthma. While the link between perinatal nutrition and lung health has been described, the underlying mechanisms remain poorly understood. There are initial data showing that inflammatory and nutrient sensing processes are involved in programming of alveolarization, pulmonary angiogenesis, and composition of extracellular matrix. Here, we provide a comprehensive overview of the current knowledge regarding the impact of perinatal metabolism and nutrition on the lung and beyond the cardiopulmonary system as well as possible mechanisms determining the individual susceptibility to CLD early in life. We aim to emphasize the importance of unraveling the mechanisms of perinatal metabolic programming to develop novel preventive and therapeutic avenues.

Value of urinary kidney injury molecule-1 levels in predicting acute kidney injury in very low birth weight preterm infants

Objective

This study aimed to evaluate the significance of urinary kidney injury molecule-1 (uKIM-1) levels in predicting acute kidney injury (AKI) and mortality in very low birth weight (VLBW) preterm infants.

Methods

This prospective, observational cohort study was conducted on 39 VLBW preterm infants. Serum creatinine (SCr) and uKIM-1 levels were measured in the first 24 and 48 to 72 hours of life. The estimated glomerular filtration rate (eGFR) was calculated. Levels of uKIM-1 were measured with an enzyme-linked immunosorbent assay.

Results

Among 39 VLBW infants, 9 (23%) developed AKI. The mortality rate was 17.9% (n = 7 neonates). There was no significant difference in SCr levels, uKIM-1 levels, or the eGFR obtained in the first 24 hours in the AKI group compared with controls. However, significant differences were found in SCr and uKIM-1 levels, and the eGFR rate at 48 to 72 hours between the groups. Levels of uKIM-1 were significantly higher in non-survivors than in survivors in the first 24 and 48 to 72 hours of life.

Conclusion

The level of uKIM-1 can be used as a simple noninvasive diagnostic method for predicting AKI and mortality, especially within 48 to 72 hours of life.

Clinical trial registration: We do not have a clinical trial registration ID. In Turkey, clinical trial registration is not required for non-drug, noninvasive, clinical studies.

Tubular and Glomerular Biomarkers of Acute Kidney Injury in Newborns

BACKGROUND

Acute Kidney Injury (AKI) is a sudden decrease in kidney function. In the early period, the highest percentage of AKI occurs among newborns hospitalized in the neonatal intensive care units, especially premature neonates. The prognosis of AKI depends on the type and severity of the cause of an injury, the accuracy and the time of diagnosis and treatment. The concentration of serum creatinine is still the main diagnostic test, although it changes in the course of AKI later than glomerular filtration rate GFR. In addition, the reliability of the determination of creatinine level is limited because it depends on many factors. New studies have presented other, more useful laboratory markers of renal function that can be measured in serum and/or in urine.

OBJECTIVE

The aim of the work was to present the latest data about tubular and glomerular biomarkers of acute kidney injury in newborns.

METHODS

We undertook a structured search of bibliographic databases for peer-reviewed research literature by using focused review topics. According to the conceptual framework, the main idea of research literature has been summarized and presented in this study.

RESULTS

The concentrations of some novel biomarkers are higher in serum and/or urine of term and preterm newborns with AKI, especially in the course of perinatal asphyxia.

CONCLUSION

In this systematic review of the literature, we have highlighted the usefulness of biomarkers in predicting tubular and/or glomerular injury in newborns. However, novel biomarkers need to prove their clinical applicability, accuracy, and cost-effectiveness prior to their implementation in clinical practice.

Selective head cooling and acute kidney injury in neonates with hypoxic ischemic encephalopathy

BACKGROUND

The reno-protective effect of therapeutic hypothermia in infants with hypoxic ischemic encephalopathy (HIE) is still debatable. We aimed to study the effect of therapeutic hypothermia on the development and progress of acute kidney injury (AKI) in neonates with HIE.

METHODS

Thirty full term infants with HIE were equally distributed between cooling group (selective head cooling) or non-cooling group (late presentation after 6 hours of birth). Serum creatinine, urine output (UOP), serum neutrophil gelatinase-associated lipocalin (NGAL), and serum cystatin C were measured at baseline, day 4 and day 10 of life.

RESULTS

The incidence of AKI as per Acute Kidney Injury Network (AKIN) criteria was comparable in cooling and non-cooling groups (40% versus 53%, respectively). Serum creatinine and UOP were significantly improved on day-4 and day-10 samples compared to base-line samples in both groups regardless of cooling. Therapeutic hypothermia was associated with a significant reduction in serum NGAL, but not cystatin C, level in day-4 and day-10 samples compared to the non-cooling group. Serum NGAL and cystatin C did not show a significant decline in day-4 and day-10 samples compared to baseline samples in both the cooled and non-cooled groups indicating an ongoing AKI.

CONCLUSIONS

Therapeutic hypothermia was associated with less renal impairment when compared to infants with HIE who were not cooled. Continuing kidney injury may persist in asphyxiated newborns despite improvement in serum creatinine and UOP.

TRIAL REGISTRATION NUMBER

NCT02683915.

Neutrophil gelatinase-associated lipocalin as predictor of acute kidney injury in neonates with perinatal asphyxia: a systematic review and meta-analysis

There is growing evidence that neutrophil gelatinase-associated lipocalin (NGAL) is a promising biomarker of acute kidney injury. The objective of this meta-analysis is to determine the accuracy of serum and urinary NGAL in the detection of acute kidney injury in neonates with perinatal asphyxia. Medline (1966-2018), Scopus (2004-2018), EMBASE (1980-2018), Clinicaltrials.gov (2008-2018), and Google Scholar (2004-2018) databases, along with the reference lists of the electronically retrieved articles, were systematically searched. Eleven studies were included, with a total number of 652 neonates. The summary sensitivity of serum NGAL was 0.818 (95% CI [0.668, 0.909]), the specificity 0.870 (95% CI [0.754, 0.936]), and the area under the curve 0.912. Regarding urinary NGAL, pooled sensitivity was calculated at 0.897 (95% CI [0.829, 0.940]), specificity at 0.729 (95% CI [0.561, 0.850]), and area under the curve at 0.899.

CONCLUSION

Serum and urinary NGAL represent candidate biomarkers with high performance in the prediction of acute kidney injury in newborns with perinatal asphyxia. Before NGAL can be widely used in clinical practice, future large prospective studies are needed to define the optimal cutoffs and accurately determine which levels are suggestive of post-asphyxial acute kidney injury. What is Known: • Acute kidney injury is a major cause of morbidity and mortality in perinatal asphyxia. • Current markers are insufficient in predicting post-asphyxial acute kidney injury. What is New: • Area under the curve for serum and urinary neutrophil gelatinase-associated lipocalin is 0.818 and 0.899, respectively. • Neutrophil gelatinase-associated lipocalin is a useful marker for detecting asphyxiated neonates at risk of developing acute kidney injury.

Copeptin level in the early prediction of cardiorenal syndrome in rats

Copeptin (CPP) has been considered as a useful marker for prediction of prognosis in heart diseases. However, CPP has not been investigated sufficiently in cardiorenal syndrome (CRS). The present study aimed to investigate the value of CPP level in predicting CRS in rats with partial nephrectomy combined with myocardial infarction (SNX + MI). A total of 60 male Sprague-Dawley rats were used to establish the CRS model by partial nephrectomy combined with MI. The rats were randomly divided into blank control (CK), SNX, MI and CRS groups. Changes in serum and urine CPP concentrations, hemodynamics, blood pressure, and renal function were examined 1-5 weeks after modeling. The predictive values of CPP in the occurrence of CRS in rats were evaluated using receiver operating characteristic (ROC) curve. The results showed that serum CPP in the CRS group in 1-5 weeks and urine CPP in 3 weeks after modeling increased significantly compared with the CK group. Also, serum B-type natriuretic peptide (BNP) in 1 and 3 weeks and urine BNP in 4-5 weeks after modeling increased significantly. No correlation was found between serum or urine CPP, BNP and BUN levels 1 week after modeling in the CRS group. The ROC curve analysis showed that the area under the curve of CRS predicted by serum CPP at 1 week was 0.908 with 56.59 pg/ml as the cutoff point, and its diagnostic sensitivity and specificity were 87.5 and 80.0%, respectively. To conclude, SNX + MI may be used to establish CRS rat model with cardiac and renal damage. Serum CPP may serve as a specific biomarker for the early prediction of CRS.