Neonatal Acute Kidney Injury

Biomarker urinary neutrophil gelatinase-associated lipocalin as a predictor of acute kidney injury in neonates

AIM

To evaluate urinary Neutrophil Gelatinase-Associated Lipocalin (uNGAL) as a predictive biomarker for Acute Kidney Injury (AKI) in neonates undergoing gastrointestinal surgery.

MATERIALS & METHODS

A prospective cohort study included 45 neonates with gastrointestinal congenital malformations who underwent abdominal surgery within the first 28 days of life at two pediatric centers in Almaty, Kazakhstan. AKI was diagnosed using modified neonatal KDIGO criteria, dividing neonates into AKI[+] and AKI[-] groups. uNGAL levels were measured pre-surgery and on postoperative days 1, 3, and 7. Statistical analysis, including ROC curve analysis, was performed using SPSS to evaluate uNGAL's sensitivity and specificity as a biomarker.

RESULTS

AKI was diagnosed in 42.2% of neonates. Pre-surgery uNGAL levels were significantly higher in the AKI group (184.4 ng/ml vs. 56.5 ng/ml). Post-surgery, uNGAL peaked at 493.9 ng/ml on day 1, with sensitivities of 89.5% and 94.7% on days 1 and 7. Specificity was highest on days 1 and 3 (96.2% and 100%). The mortality rate among AKI-affected neonates was 31.5%.

CONCLUSION

uNGAL is a sensitive and specific biomarker for early AKI detection in neonates post-gastrointestinal surgery, enabling timely interventions and potentially reducing mortality.

Expanded discussion of kidney health monitoring for critically ill term and late preterm infants after acute kidney injury: a report from the Neonatal Kidney Health Consensus Workshop

BACKGROUND

Acute kidney injury (AKI) is common in the neonatal intensive care unit (NICU) and is associated with increased morbidity and mortality. Mounting evidence suggests infants with AKI in the NICU have higher risks of long-term kidney dysfunction, such as chronic kidney disease. However, guidelines for outpatient kidney-focused follow-up practices are lacking.

METHODS

As part of the National Institutes of Health-sponsored Consensus Workshop to Address Kidney Health in Neonatal Intensive Care Unit Graduates, a multidisciplinary workgroup within the US performed an in-depth review of the medical literature on term and late preterm (i.e. ≥ 34 weeks gestation) neonates admitted to the NICU with AKI to inform consensus recommendations for outpatient kidney health monitoring for high-risk and at-risk infants.

RESULTS

In this modified Delphi consensus statement, the workgroup developed three consensus recommendations and identified priority research gaps and opportunities for future study. Specific recommendations include completing a NICU discharge kidney health evaluation followed by a comprehensive kidney health assessment six months after discharge for high-risk infants and at two years of age for high-risk and at-risk infants.

CONCLUSIONS

Critically ill term and late preterm infants with AKI have an increased risk of long-term kidney dysfunction and merit evaluation at NICU discharge with subsequent comprehensive kidney health assessments based on risk factors. Current research gaps and opportunities for improved care include identifying optimal pre-discharge planning approaches, examining the impacts of different etiologies and severity of AKI on long-term kidney and overall health, exploring modification to current AKI diagnosis standards, and development of high-yield educational tools for families and providers.

Acute kidney injury and energy metabolism

Acute kidney injury (AKI) predominantly affects hospitalized patients, particularly those in intensive care units, and has emerged as a significant global public health concern. Several factors, including severe cardiovascular disease, surgery-induced renal ischemia, nephrotoxic drugs, and sepsis, contribute to the development of AKI. Despite the implementation of various clinical strategies to prevent or treat AKI, its morbidity and mortality remain high, and there are no clinically effective therapeutic agents available. The limitations of traditional renal function markers (such as urine output, serum creatinine, and urea nitrogen levels), including their delayed response and insensitivity, underscore the urgent need for novel early biomarkers to facilitate the timely diagnosis of AKI. The proximal tubular epithelial cells in the kidney play a central role in both the onset and progression of AKI. These cells are highly metabolically active and have a substantial energy demand, primarily relying on fatty acid oxidation to meet their energy needs. Acylcarnitines are crucial in transporting fatty acids from the cytoplasm into the mitochondrial matrix for β-oxidation, which generates energy essential for maintaining cellular function and viability. This review aims to summarize the current understanding of AKI, including its triggers, classification, underlying mechanisms, and potential biomarkers. Special emphasis is placed on the role of fatty acid and carnitine metabolism in AKI, with the goal of providing a theoretical foundation for future investigations into AKI mechanisms and the identification of early diagnostic biomarkers.

Review of Precision Medicine and Diagnosis of Neonatal Illness

Background/Objectives: Precision medicine is a state-of-the-art medicine tactic that tailors information about people's genes, environment, and lifestyle to aid the prevention, diagnosis, and treatment of various diseases to provide an overview of the currently available knowledge and applicability of precision medicine in the diagnosis of different cases admitted to the NICU, such as encephalopathies, respiratory distress syndrome of prematurity, hemodynamic instability, acute kidney injury, sepsis, and hyperbilirubinemia. Methods: The authors searched databases, such as PubMed and PubMed Central, for the terms neonatal "precision medicine", "personalized medicine", "genomics", and "metabolomics", all related to precision medicine in the diagnosis of neonatal illness. The related studies were collected. Results: The review highlights the diagnostic approach that serves to implement precision medicine in the NICU and provide precision diagnosis, monitoring, and treatment. Conclusions: In this review, we projected several diagnostic approaches that provide precision identification of health problems among sick neonates with complex illnesses in the NICU; some are noninvasive and available in ordinary healthcare settings, while others are invasive or not feasible or still in ongoing research as machine learning algorithms. Future studies are needed for the wide implementation of artificial intelligence tools in the diagnosis of neonatal illnesses.

Population Pharmacokinetics of Caffeine in Infants with Hypoxic-Ischemic Encephalopathy: A Phase I, Dose-Escalating Trial

The mainstay of treatment for infants with hypoxic-ischemic encephalopathy (HIE) is cooling. Caffeine may be an important adjunct to cooling and provide neuroprotection via its anti-inflammatory and anti-oxidative properties. This study aimed to characterize caffeine pharmacokinetics in term infants with HIE receiving cooling. In this phase 1, dose-escalating study, enrolled infants received IV caffeine 20 mg/kg followed by up to two daily doses of 5 or 10 mg/kg. A population pharmacokinetic analysis was performed using NONMEM (v7.5). The effects of clinical covariates, including cooling, on pharmacokinetic parameters were evaluated. Dosing simulations were performed to evaluate the percentage of plasma exposures in the reference range (15-25 mg/L). Seventeen infants were included in model development. A one-compartment model best fit the data. Population clearance was 0.445 L/h/70 kg and volume of distribution was 87.1 L/70 kg. Current dosing regimens (20 mg/kg followed by 5 mg/kg) resulted in 89.5% of infants having at least one simulated exposure below the reference range across the dosing interval. Dosing regimens of 30 mg/kg followed by 5 or 10 mg/kg were predicted to result in more than half of infants achieving simulated exposures in the reference range, with ≤20% of infants having simulated exposures in the toxic range (>46 mg/L). Term infants with HIE had similar weight-normalized clearance but higher weight-normalized volume of distribution compared to prior studies in preterm infants without HIE or cooling. While exposure targets for neuroprotection in HIE are unknown, this phase 1 study suggests alternate dosing strategies should be considered in future studies.

Vascular Access for Renal Replacement Therapy in Neonates and Infants: A Single Center Experience

INTRODUCTION

Neonatal renal replacement therapy (RRT) is a treatment modality used for severe kidney failure. Historically, its use has been limited in small infants due to circuits with large extra-corporeal volumes that require large double lumen vascular catheters. We sought to review our institution's experience with vascular access and overall survival in infants who receive RRT.

METHODS

A retrospective chart review of infants less than 5 kg (kg) was performed at our free-standing children's hospital from January 2016 to July 2023. We assessed the number of catheters used per patient, location of catheter placements, size of catheter, duration of treatment, reasons for line removal, and mortality.

RESULTS

A total of 93 neonatal patients were identified who underwent RRT. Thirty-two patients (34.4%) required more than one catheter, with a total of 145 catheters placed for this cohort. The median (IQR) weight at insertion was 3.3 kg (2.7-4.0). The most common location for placement was the right internal jugular vein (n = 114, 78.6%). Patients required catheters for RRT for a median (IQR) of 16 days (7-39). Six patients underwent catheter placement at a weight of less than 2 kg. Nineteen total patients went on to peritoneal dialysis (20.4%). Fifty-three patients died during their admission (57.0%).

CONCLUSION

To our knowledge this is the largest review of catheter use for RRT in infants within an intensive care unit and it reveals the success in treating renal failure in even the smallest infants.

LEVEL OF EVIDENCE

IV, Treatment Study.

Association between platelet count and neonatal acute kidney injury: a cohort study using the medical information mart for intensive care III database

OBJECTIVE

A decrease in platelet count has been reported to be associated with several neonatal inflammatory diseases, including sepsis and necrotizing enterocolitis; while its association with neonatal acute kidney injury (AKI) has not been reported. This study aims to explore the association between platelet count and neonatal AKI.

METHODS

This was a retrospective cohort study based on the Medical Information Mart for Intensive Care III (MIMIC-III) database. Data were extracted based on baseline characteristics, comorbidities, vital signs, laboratory parameters, and intervention measures. Logistic regression analysis was used to assess the association between platelet count and AKI, and results were shown as odds ratios (OR) with 95% confidence intervals (CI).

RESULTS

A total of 1,576 neonates were finally included in the analysis. After adjusting birth weight, sepsis, patent ductus arteriosus, hematocrit, percentage of neutrophils, and vasopressor use, we found that platelet count in the lowest quartile (Q1) was significantly associated with the higher odds of AKI than platelet count in the highest quartile (Q4) (OR = 1.70, 95% CI: 1.01-2.87).

CONCLUSIONS

Low platelet count was associated with the high odds of AKI in the neonatal intensive care unit (NICU), indicating that platelet count might be a biomarker for neonatal AKI. Large-scale multicenter studies should be performed to verify the results.

Evaluation of risk factors associated with acute kidney injury in a level IV regional NICU

BACKGROUND

Intervening on neonates at risk for developing acute kidney injury (AKI) improves safety and clinical outcomes. This study sought to evaluate risk factors associated with AKI in a level IV neonatal intensive care unit (NICU).

METHODS

Single-center, case-control study of patients with corrected gestational age (GA) ≤44 weeks from 2018 to 2022. Cases were those that developed AKI after day 4 of life. Controls were the next neonate admitted to the same NICU team that met inclusion criteria but did not develop AKI. Neonatal and maternal factors, nephrotoxic medication administration, and procedures were analyzed to identify risk factors associated with AKI using univariate and multivariate analyses.

RESULTS

A total of 94 patients were included: 47 cases and 47 controls. GA <27 weeks, birth weight <1500 grams, low APGAR score, intubation at birth, bronchopulmonary dysplasia (BPD), patent ductus arteriosus (PDA), necrotizing enterocolitis (NEC), and sepsis were associated with AKI on univariate analysis. Most cases (89.4%) had >4 risk factors, and this was associated with a 13.1-fold increase in the odds of developing AKI. Multivariate analysis identified GA <27 weeks (OR 7.7, 95% CI 1.7-34.4), vasopressor and/or inotrope administration (OR 4.4, 95% CI 1.2-23.8), and diagnosis of PDA (OR 6.9, 95% CI 1.5-31.3) as independent predictors of AKI.

CONCLUSIONS

Risk factors associated with AKI were identified, and a 13.1-fold increase in AKI was found when >4 risk factors were present. This information may be used to expand renal acuity surveillance programs focusing on high-risk medication evaluation, demographic, and clinical factors.

Total bilirubin level is associated with acute kidney injury in neonates admitted to the neonatal intensive care units: based on MIMIC-III database

OBJECTIVE

The objective of this study was to investigate the association between total bilirubin and acute kidney injury (AKI) in neonates admitted to neonatal intensive care units (NICU).

METHODS

All data utilized were extracted from Medical Information Mart for Intensive Care-III (MIMIC-III) in this retrospective cohort study. The primary outcome was the occurrence of AKI during hospitalization in the NICU, and the exposure was the initial measurement of total bilirubin levels within 24 h of neonatal admission to the NICU. The relationship between serum total bilirubin and AKI was evaluated by employing univariate and multivariate logistic regression models. Additionally, subgroup analyses were conducted based on birth weight, sepsis, and mechanical ventilation.

RESULTS

This retrospective cohort study included a population of 1,726 neonates, and 95 neonates developed AKI. Total bilirubin, as a continuous variable, was linked with decreased AKI risk among neonates admitted to the NICU [odds ratio (OR) = 0.77, 95% confidence interval (CI): 0.64-0.92]. Similarly, when total bilirubin levels were categorized by tertiles, tertiles 3 showed a significant association with decreased AKI risk (OR = 0.39, 95%CI: 0.19-0.83). The relationship of total bilirubin level and AKI was also existent among neonates admitted to the NICU who were underweight, had not sepsis, and received mechanical ventilation.

CONCLUSION

Total bilirubin level may be a protective factor for the risk of developing AKI.

Contrast-Enhanced Ultrasound (CEUS) and Ultra-Microangiography (UMA) in Critically Ill Children with Acute Kidney Injury

Acute kidney injury (AKI) is an acute condition of impaired kidney function with decreased glomerular filtration rate, which results in dysregulation in volume, electrolyte, and acid-base equilibrium. AKI can be a life-threatening condition and can also lead to chronic kidney disease. It is important to diagnose AKI early in the course of the disease or to predict its development, as this can influence therapeutic decisions, outcome, and, consequently, the prognosis. In clinical practice, an elevated serum creatinine concentration remains the most common laboratory indicator for diagnosing AKI. However, due to the delay in its rise, creatinine levels are often insensitive and inaccurate for early diagnosis. Novel biomarkers of kidney tubular injury and the renal angina index have shown promise in predicting AKI earlier and more accurately. Contrast-enhanced ultrasonography (CEUS) and ultra-microangiography (UMA) are radiological methods that can quantify renal microperfusion and may be able to predict the development of AKI. They have not yet been used for quantifying renal perfusion in children with risk factors for developing AKI. Further research is needed to compare these sonographic techniques with the renal angina index and emerging kidney injury biomarkers for predicting acute kidney injury (AKI) in both children and adults.

Risk factors for acute kidney injury in preterm neonates after noncardiac surgery: a single-center retrospective cohort study

Postoperative acute kidney injury (AKI) is a common complication that is associated with chronic kidney disease, early postsurgical mortality, and prolonged hospital stays. Preterm neonates who undergo surgery are at risk factors for AKI due to underdeveloped kidneys. To date, little is known about the incidence and perioperative risk factors for AKI in preterm neonates undergoing noncardiac surgery. Preterm neonates who underwent noncardiac surgery between January May 1, 2020, and February 28, 2023, were enrolled in the trial according to the inclusion criteria. Both multivariable and logistic regression analyses were used to analyze the associations between characteristic data and AKI. In total, 106 preterm neonates met the inclusion criteria, and 25 preterm neonates (23.6%) developed postoperative AKI. Multivariate analysis revealed that the factors associated with AKI were gestational age < 32 weeks [OR: 4.88; 95% CI (1.23-19.42)], preoperative sepsis [OR: 3.98; 95% CI (1.29-12.28)], and intraoperative hypotension [OR: 3.75; 95% CI (1.26-11.15)]. Preterm neonates who developed AKI were more likely to have longer hospital length of stays (38 [18,69] days vs. 21[12,46]) and higher medical costs (93,181.6 [620450.0,173,219.0] ￥ vs. 58,134.6 [31015.1,97,224,1) ￥ than neonates who did not develop AKI. Preterm neonates who underwent noncardiac surgery had a high incidence of AKI. Independent risk factors for AKI in preterm neonates who underwent noncardiac surgery were low gestational age, preoperative sepsis, and intraoperative hypotension. Preterm neonates who developed AKI were more likely to have longer hospital stays and higher medical costs.

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.

Acute Kidney Injury in Neonates Admitted to a Low-Resource Neonatal Intensive Care Unit in Lusaka, Zambia

Background

Neonatal acute kidney injury (nAKI) has been reported to be common among neonates admitted to the Neonatal Intensive Care Unit (NICU) and is associated with increased mortality and prolonged duration of hospital stay. However, data on this entity from sub-Saharan Africa are scanty.

Objectives

This study aimed to assess the burden, risk factors, and short-term outcomes of nAKI in neonates admitted to a low-resource NICU in Zambia.

Design

The design of the study is a prospective cohort study.

Setting

The setting of this study was the NICU at the Women and Newborn Hospital of the University Teaching Hospitals (WNBH-UTHs).

Patients

In total, 322 neonates who were admitted to the NICU between November 2021 and December 2022.

Methods

A serum creatinine was determined on all patients at admission (within 24 hours), at 72 hours and day 7. The modified neonatal Kidney Disease: Improving Global Outcome (KDIGO) Criteria were used to define nAKI. Data were extracted using a predesigned form and analyzed using SPSS. A P-value less than .05 was considered statistically significant.

Results

The prevalence of nAKI was 13.7% (44/322). On multivariable regression analysis, antepartum hemorrhage (adjusted odds ratio [AOR] 5.58; 95% confidence interval [CI]: [1.62-19.13], P = .007), vomiting in the neonate (AOR 5.76; 95% CI: [1.10-30.32], P = .04), history of use of unit second-line antibiotics, meropenem (AOR 4.37; 95% CI: [1.97-9.69], P < .001), and ciprofloxacin (AOR 4.53; 95% CI: [1.22-16.84], P = .02) were associated with increased risk of nAKI. Acute kidney injury (AKI) was significantly associated with longer length of hospital stay and higher mortality (P < .05).

Limitations

The study did not use the urine output criteria to define nAKI and this may have led to an underestimation of nAKI prevalence. Additionally, kidney, ureter, and bladder ultrasound was not performed on any of the study participants.

Conclusion

AKI is common in neonates admitted to the NICU at WNBH-UTHs, and it is associated with a higher risk of mortality and prolonged length of hospital stay. Further studies among the various NICU sub-populations are needed to better characterize risks and outcomes.

Incidence and predictors of acute kidney injury among asphyxiated neonates in comprehensive specialized hospitals, northwest Ethiopia, 2023

Acute kidney injury (AKI) is characterized by a sudden decline in the kidneys' abilities to remove waste products and maintain water and electrolyte homeostasis. This study aims to determine the incidence and predictors of acute kidney injury among neonates with perinatal asphyxia admitted at the neonatal intensive care unit of West Amhara Comprehensive Specialized Hospital, Northwest Ethiopia, 2023. Multicentred institution-based retrospective follow-up study was conducted from October 1, 2021, to September 30, 2023, among 421 perinatal asphyxia neonates. A simple random sampling technique was used. The data were collected using a data extraction checklist from the medical registry of neonates. The collected data were entered into EPI-DATA V.4.6.0.0. and analyzed using STATA V.14. The Kaplan-Meier failure curve and log-rank test were employed. Bivariable and multivariable Cox regression was carried out to identify predictors of Acute kidney injury. Statistical significance was declared at a p ≤ 0.05. The overall incidence of AKI was 54 (95% CI 47.07-62.51) per 100 neonate days. C/S delivery (AHR = 0.64; (95% CI 0.43-0.94), prolonged labor (AHR = 1.43; 95% CI 1.03-1.99) low-birth weight times (AHR = 1.49; (95% CI 1.01-2.20), stage three HIE(AHR: 1.68; (95% CI (1.02-2.77), No ANC follow up (AHR = 1.43; 95% CI 1.9 (1.07-3.43) and Hyperkalemia (AHR = 1.56; 95% CI 1.56 (1.05-2.29); 95% CI) were significant predictors. The incidence rate of acute kidney injury was higher than in other studies conducted on other groups of neonates. Cesarean section delivery, prolonged low birthweight, no Anc follow-up, stage 3 HIE, and neonatal hyperkalemia were predictors of acute kidney injury. However, it needs further prospective study. Therefore, the concerned stakeholders should give due attention and appropriate intervention to these predictors.

Acute Kidney Injury in Neonates: A Meta-Analysis

BACKGROUND AND OBJECTIVE

There is a paucity of pooled synthesized data on the epidemiology of neonatal acute kidney injury (AKI). Our objective with this study is to systematically assess the worldwide incidence of AKI in neonates.

METHODS

We searched 3 electronic databases (Embase, PubMed, Web of Sciences) from January 2004 to December 2022 without language restrictions. We included cohort and cross-sectional studies that reported the incidence of AKI or associated mortality in neonates. Eligible studies had at least 10 participants and used standard criteria (Acute Kidney Injury Network/Pediatric Risk, Injury, Failure, Loss, End Stage Renal Disease (pRIFLE)/ Kidney Disease Improving Global Outcomes) to define AKI. Two authors independently retrieved data on demographic characteristics, clinical setting, and outcomes (incidence and AKI-associated mortality) using a semi-structured proforma and assessed the risk of bias. We used a random-effects meta-analysis to calculate pooled estimates with 95% confidence intervals.

RESULTS

We included 201 studies (98 228 participants) from 45 countries. The incidence of any stage AKI was 30% (95% confidence interval 28-32), and that of severe AKI was 15% (14-16). Overall, AKI-associated mortality was 30% (27-33). The odds of mortality were higher (odds ratio 3.4; 2.9-4.0) in neonates with AKI compared with those without AKI. We found that perinatal asphyxia, sepsis, patent ductus arteriosus, necrotizing enterocolitis, and nephrotoxic medications were significant risk factors for AKI. Significant heterogeneity in the pooled estimates was a limitation of this study.

CONCLUSIONS

AKI was observed in one-third of the neonates and was associated with increased risk of mortality. The incidence of AKI was almost similar in neonates with perinatal asphyxia and sepsis, but mortality was higher in the former group.

Evaluation of pharmacokinetic pharmacodynamic target attainment of meropenem in pediatric patients

BACKGROUND

Meropenem is a widely used carbapenem for treating severe pediatric infections. However, few studies have assessed its pharmacokinetics/pharmacodynamics (PK/PD) in pediatric patients. This study aimed to evaluate the proportion of Saudi pediatric patients achieving the PK/PD target of meropenem.

METHODS

A prospective observational study was conducted at King Saud University Medical City from July to September 2022. Pediatric patients receiving meropenem for suspected or proven infections were included in the study. The primary outcome was the percentage of patients achieving the recommended PK/PD target for critically ill or non-critically ill pediatric patients.

RESULTS

The study included 30 patients (nine neonates and 21 older pediatric patients). All neonates were critically ill. Among them, 55 % achieved the PK/PD target of 100 % free time above the MIC. In older ICU pediatric patients, only 11 % attained this target, whereas 58 % of older pediatrics in the general wards achieved the PK/PD target of 50 % free time above the MIC. Augmented renal clearance (ARC) was identified in 57 % of our pediatric patient population, none of whom achieved the recommended PK/PD targets. The median trough concentrations in patients with and without ARC were 0.75 and 1.3 μg/mL, respectively (P < 0.05).

CONCLUSIONS

The majority of patients in our cohort did not achieve the PK/PD target for meropenem. ARC emerged as a major risk factor for target attainment failure in both critically ill and non-critically ill pediatric patients.

Sustained acute kidney injury as an independent risk factor for neurodevelopmental and growth outcomes in a single NICU center

PURPOSE

Acute kidney injury (AKI) is commonly seen in neonatal intensive care units (NICUs) and is potentially associated with adverse prognoses in later stages of life. Our study evaluated the impact of sustained AKI (SAKI) on both neurodevelopmental impairment (NDI) and early growth restriction (EGR) in neonates.

METHODS

This case-control study retrospectively analyzed the medical records of neonates diagnosed with SAKI in the NICU of a tertiary medical center during the period from January 2007 to December 2020. Cases without subsequent follow-up and those resulting in death were excluded. We analyzed demographic, biochemical, and clinical outcome data.

RESULTS

Of the 93 neonates with SAKI, 51 cases (54.8%) were included in this study, while 42 cases (45.2%) were excluded due to a lack of follow-up or death. An age-matched control group comprised 103 neonates, who had never experienced AKI or SAKI, were selected at random. In total, 59 (38.3%) cases were identified as NDI and 43 (27.9%) as EGR. Multivariate analysis revealed that patients with SAKI had significantly higher risks of developing NDI (odds ratio, [OR] = 4.013, p = 0.001) and EGR (OR = 4.894, p < 0.001). The AKI interval had an area under the receiver operating characteristic curve of 0.754 for NDI at 9.5 days and 0.772 for EGR at 12.5 days.

CONCLUSIONS

SAKI is an independent risk factor for both NDI and EGR in neonates. Consequently, regular monitoring, neurological development assessments, and appropriate nutritional advice are crucial to these infants who have experienced renal injury.

Low incidence of acute kidney injury in VLBW infants with restrictive use of mechanical ventilation

BACKGROUND

We assessed the incidence of and risk factors for acute kidney injury (AKI) in very low birthweight infants (VLBW) in a center with a specific neonatal management protocol focusing on avoidance of early mechanical ventilation (MV).

METHODS

This retrospective single center analysis includes 128 infants born in 2020 with a gestational age ≥ 22 weeks who were screened for AKI using the nKDIGO criteria.

RESULTS

AKI was identified in 25/128 patients (19.5%) with eight of them (6.3%) presenting with severe AKI. Low gestational age, birthweight and 10-minute Apgar score as well as high CRIB-1 score were all associated with incidence of AKI. Forty-five percent of the infants with MV developed AKI vs. 8.9% of those without MV (p < 0.001). Early onset of MV and administration of more than 3 dosages of NSAIDs for patent duct were identified as independent risk factors for AKI in a logistic regression analysis.

CONCLUSIONS

We report a substantially lower frequency of AKI in VLBW infants as compared to previous studies, along with a very low rate of MV. A neonatal protocol focusing on avoidance of MV within the first days of life may be a key factor to decrease the risk of AKI in immature infants.

Impact of preterm birth on kidney health and development

Preterm birth, defined as birth before the gestational age of 37 weeks, affects 11% of the newborns worldwide. While extensive research has focused on the immediate complications associated with prematurity, emerging evidence suggests a link between prematurity and the development of kidney disease later in life. It has been demonstrated that the normal course of kidney development is interrupted in infants born prematurely, causing an overall decrease in functional nephrons. Yet, the pathogenesis leading to the alterations in kidney development and the subsequent pathophysiological consequences causing kidney disease on the long-term are incompletely understood. In the present review, we discuss the current knowledge on nephrogenesis and how this process is affected in prematurity. We further discuss the epidemiological evidence and experimental data demonstrating the increased risk of kidney disease in these individuals and highlight important knowledge gaps. Importantly, understanding the intricate interplay between prematurity, abnormal kidney development, and the long-term risk of kidney disease is crucial for implementing effective preventive and therapeutic strategies.

Urinary Concentration of Renal Biomarkers in Healthy Term Neonates: Gender Differences in GST-pi Excretion

BACKGROUND Serum creatinine, the criterion standard in assessment of renal function, is not reliable for the neonatal period because of its dependence on renal immaturity and maternal creatinine levels. Thus, it is important to study other biomarkers of renal function in neonates. The present study aimed to measure the urinary concentration of renal biomarkers: calbindin, clusterin, GST-pi (glutathione-S-transferase-alpha), KIM-1 (kidney injury molecule 1), MCP-1 (monocyte chemoattractant protein-1), and B2M (beta 2-microglobulin) in healthy term neonates. MATERIAL AND METHODS In the study, we included 80 healthy term neonates - 40 females and 40 males. We collected the neonates' urine on their first day of life. Urinary concentrations of calbindin, clusterin, KIM-1, MCP-1, and B2M were assessed using an immunoassay for kidney toxicology research. Because dilution of the urine affects the concentrations of urinary biomarkers, we normalized them to the concentration of urinary creatinine (Cr) and present them as biomarker/Cr ratios. RESULTS We obtained the following values of the assessed biomarker/Cr ratios (median [Q1-Q3]): calbindin/Cr.: 197.04 (56.25-595.17), KIM-1/Cr: 0.09 (0.04-0.18), MCP-1/Cr: 0.05 (0.02-0.14), B2M/Cr: 126.12 (19.03-342.48), GST-pi/Cr in boys: 1.28 (0.46-3.77), GST-pi/Cr in girls: 8.66 (2.51-27.82), clusterin/Cr: 4.55 (1.79-12.97) ng/mg Cr. CONCLUSIONS We showed the urinary levels of calbindin, clusterin, GST-pi, KIM-1, MCP-1, B2M in white, West Slavic, healthy term neonates. We found that in there is an association between female sex and a higher urinary GST-pi excretion, but urinary excretion of calbindin, clusterin, KIM-1, MCP-1, and B2M is sex-independent. The urinary levels of the assessed biomarkers do not depend on the method of delivery.

Nutrition for critically ill children and neonates requiring dialysis: Application of clinical practice recommendations

Approximately 30% of all children and neonates admitted to the intensive care unit (ICU) experience acute kidney injury (AKI). Children with AKI are largely poorly fed and experience high rates of malnutrition. Nutrition prescription and provision are exceptionally challenging for critically ill neonates, infants, and children with AKI given the dynamic nature of AKI and its respective treatment modalities. Managing the nutrition prescription of critically ill neonates, infants, and children with AKI requires nutrition support clinicians to have a high-level understanding of the various treatment modalities for AKI, which can affect the patient's protein, fluid, electrolyte, and mineral needs. Accurate and timely nutrition assessment in critically ill neonates and children with AKI can be flawed owing to difficulty obtaining accurate anthropometric parameters. Recently, the Pediatric Renal Nutrition Taskforce introduced clinical practice recommendations for the nutrition management of children with AKI. In this review, we will discuss the practical implications of these recent guidelines and work to bridge the knowledge and practice gaps for pediatric and neonatal nutrition support clinicians providing nutrition therapy for patients with AKI in the ICU. We also appraise special nutrition-related considerations for neonates with AKI given newer available renal replacement treatment modalities.

Transient Hyperechogenic Medullary Pyramids in a Neonate With Acute Kidney Injury

A neonate with acute kidney injury can present with decreased urine output and signs of dehydration. Sonography is used to evaluate the kidneys for structural deformities. A normal sonographic image of a neonatal kidney would show hypoechoic pyramids of the medulla. However, less frequently occurring neonatal transient renal failure with renal medullary hyperechogenicity has been linked to severe perinatal renal damage, kidney abnormalities, or nephrocalcinosis. A simple conventional sonography in neonates can be helpful in predicting the severity of renal damage in such cases. Hyperechogenecity of the medulla in contrast to the normal hypoechogenic medulla of normal neonates can be due to multiple causes. However one must bear in mind that this finding of hyperechoic tips of renal pyramids is not indicative of intrinsic renal disease and subsides without intervention if physiologic or with rehydration if due to hypernatraemic dehydration. It is important for a physician to know about this physiological variant seen in neonates who present with dehydration.

An Exploratory Review on the Potential of Artificial Intelligence for Early Detection of Acute Kidney Injury in Preterm Neonates

A preterm birth is a live birth that occurs before 37 completed weeks of pregnancy. Approximately 15 million babies are born preterm annually worldwide, indicating a global preterm birth rate of about 11%. Up to 50% of premature neonates in the gestational age (GA) group of <29 weeks' gestation will develop acute kidney injury (AKI) in the neonatal period; this is associated with high mortality and morbidity. There are currently no proven treatments for established AKI, and no effective predictive tool exists. We propose that the development of advanced artificial intelligence algorithms with neural networks can assist clinicians in accurately predicting AKI. Clinicians can use pathology investigations in combination with the non-invasive monitoring of renal tissue oxygenation (rSO2) and renal fractional tissue oxygenation extraction (rFTOE) using near-infrared spectroscopy (NIRS) and the renal resistive index (RRI) to develop an effective prediction algorithm. This algorithm would potentially create a therapeutic window during which the treating clinicians can identify modifiable risk factors and implement the necessary steps to prevent the onset and reduce the duration of AKI.

Association of intrauterine growth restriction and low birth weight with acute kidney injury in preterm neonates

BACKGROUND

Preterm birth alters nephrogenesis and reduces the total nephron number. Intrauterine growth restriction (IUGR) seems to worsen nephron loss, but only a few studies have investigated its role in neonatal kidney impairment. We investigated whether IUGR, defined as reduced estimated fetal growth and/or placental flow alterations and low birth weight z-score, increases the risk of developing acute kidney injury (AKI) in very preterm infants.

METHODS

We performed a retrospective study including infants born with a birth weight (BW) ≤ 1500 g and/or gestational age (GA) ≤ 32 weeks admitted to our center between January 2016 and December 2021. Neonatal AKI was defined according to the neonatal KDIGO classification based on the decline of urine output and/or creatinine elevation. We used multivariable linear regressions to verify the association between AKI and GA, BW z-score, IUGR definition, and hemodynamically significant patent ductus arteriosus (PDA).

RESULTS

We included 282 infants in the analysis, with a median (IQR) GA = 29.4 (27.4, 31.3) weeks, BW = 1150 (870, 1360) g, and BW z-score =  - 0.57 (- 1.64, 0.25). AKI was diagnosed in 36 (13%) patients, and 58 (21%) had PDA. AKI was significantly associated with BW z-score (beta (std. error) =  - 0.08 (0.03), p = 0.008) and severe IUGR (beta (std. error) = 0.21 (0.08), p = 0.009), after adjusting for GA and PDA.

CONCLUSIONS

Our data suggest that low BW z-score and IUGR could represent adjunctive risk factors for kidney impairment in preterm babies. A higher resolution version of the Graphical abstract is available as Supplementary information.

Infections and Acute Kidney Injury: A Global Perspective

Globally, there are an estimated 13.3 million cases of acute kidney injury (AKI) annually. Although infections are a common cause of AKI globally, most infection-associated AKI occurs in low- and lower-middle-income countries. There are marked differences in the etiology of infection-associated AKI across age groups, populations at risk, and geographic location. This article provides a global overview of different infections that are associated commonly with AKI, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), human immunodeficiency virus, malaria, dengue, leptospirosis, tick-borne illnesses, and viral hemorrhagic fevers. Further discussion focuses on infectious conditions associated with AKI including sepsis, diarrheal diseases and pregnancy, peripartum and neonatal AKI. This article also discusses the future of infection-associated AKI in the framework of climate change. It explores how increased investment in achieving the sustainable development goals may contribute to the International Society of Nephrology's 0 by 25 objective to curtail avoidable AKI-related fatalities by 2025.

Sex differences in long-term kidney fibrosis following neonatal nephron loss during ongoing nephrogenesis

BACKGROUND

Clinical studies suggest that female sex plays a protective role in the development and progression of kidney disease. Recent experimental studies indicate that in male rats early nephron loss under ongoing nephrogenesis is accompanied by severe long-term sequelae. In humans, nephron formation occurs mainly in the third trimester, ceasing with 36 weeks of gestation. Due to perinatal complications, preterm infants delivered during this vulnerable period may undergo acute nephron loss. In rats nephrogenesis persists until postnatal day 10, reflecting the situation of human preterms with persisting nephrogenesis. In our animal model of neonatal uninephrectomy, female and male rats were uninephrectomized at day 1 of life. Hypothesizing sex-dependent differences, long-term renal outcome was assessed after 1 year.

RESULTS

In both sexes, neonatal uninephrectomy was not followed by arterial hypertension at 1 year of age. Compensatory weight gain and glomerular hypertrophy of the remaining kidney occurred in uninephrectomized female and male animals. Selected markers of interstitial inflammation and fibrosis were regulated sex-dependently. The expression of monocyte chemoattractant protein-1 was increased in females, while tubulointerstitial infiltration by M1 macrophages was significantly higher in males after neonatal uninephrectomy. Neonatally uninephrectomized male rats had more glomerulosclerosis and podocyte damage compared to females, which was assessed by a semiquantitative score and desmin staining. RT-PCR revealed that after neonatal uninephrectomy in the remaining contralateral kidney of female rats the expression of candidate genes of renal development and function, i.e., wt-1, nephrin, synaptopodin, gdnf, and itga8 was higher than in males.

CONCLUSIONS

Based on these observations we conclude that female sex is protective in the long-term response of the kidney to acute nephron loss under active nephrogenesis.

Nutrition and Intestinal Rehabilitation of Children With Short Bowel Syndrome: A Position Paper of the ESPGHAN Committee on Nutrition. Part 1: From Intestinal Resection to Home Discharge

Short bowel syndrome (SBS) is the leading cause of intestinal failure (IF) in children. The mainstay of treatment for IF is parenteral nutrition (PN). The aim of this position paper is to review the available evidence on managing SBS and to provide practical guidance to clinicians dealing with this condition. All members of the Nutrition Committee of the European Society for Paediatric Gastroenterology Hepatology and Nutrition (ESPGHAN) contributed to this position paper. Some renowned experts in the field joined the team to guide with their experience. A systematic literature search was performed from 2005 to May 2021 using PubMed, MEDLINE, and Cochrane Database of Systematic Reviews. In the absence of evidence, recommendations reflect the expert opinion of the authors. Literature on SBS mainly consists of retrospective single-center experience, thus most of the current papers and recommendations are based on expert opinion. All recommendations were voted on by the expert panel and reached >90% agreement. The first part of this position paper focuses on the physiological mechanism of intestinal adaptation after surgical resection. It subsequently provides some clinical practice recommendations for the primary management of children with SBS from surgical resection until discharged home on PN.

Developmental Pharmacokinetics of Antibiotics Used in Neonatal ICU: Focus on Preterm Infants

Neonatal Infections are among the most common reasons for admission to the intensive care unit. Neonatal sepsis (NS) significantly contributes to mortality rates. Empiric antibiotic therapy of NS recommended by current international guidelines includes benzylpenicillin, ampicillin/amoxicillin, and aminoglycosides (gentamicin). The rise of antibacterial resistance precipitates the growth of the use of antibiotics of the Watch (second, third, and fourth generations of cephalosporines, carbapenems, macrolides, glycopeptides, rifamycins, fluoroquinolones) and Reserve groups (fifth generation of cephalosporines, oxazolidinones, lipoglycopeptides, fosfomycin), which are associated with a less clinical experience and higher risks of toxic reactions. A proper dosing regimen is essential for effective and safe antibiotic therapy, but its choice in neonates is complicated with high variability in the maturation of organ systems affecting drug absorption, distribution, metabolism, and excretion. Changes in antibiotic pharmacokinetic parameters result in altered efficacy and safety. Population pharmacokinetics can help to prognosis outcomes of antibiotic therapy, but it should be considered that the neonatal population is heterogeneous, and this heterogeneity is mainly determined by gestational and postnatal age. Preterm neonates are common in clinical practice, and due to the different physiology compared to the full terms, constitute a specific neonatal subpopulation. The objective of this review is to summarize the evidence about the developmental changes (specific for preterm and full-term infants, separately) of pharmacokinetic parameters of antibiotics used in neonatal intensive care units.

Early urine output monitoring in very preterm infants to predict in-hospital neonatal outcomes: a bicentric retrospective cohort study

OBJECTIVE

To evaluate whether urine output (UO), rarely assessed in the literature, is associated with relevant neonatal outcomes in very preterm infants, and which UO threshold may be the most clinically relevant.

DESIGN

Retrospective cohort study.

SETTING

Two Level IV neonatal intensive care units.

PATIENTS

Very preterm infants born between 24^0/7 and 29^6/7 weeks of gestation documented with eight UO measurements per day between postnatal day 1 and day 7.

MAIN OUTCOME MEASURES

Composite outcome defined as death before discharge, or moderate to severe bronchopulmonary dysplasia, or severe brain lesions. The association between this outcome and UO was studied using several UO thresholds.

RESULTS

Among 532 infants studied, UO <1.0 mL/kg/hour for at least 24 consecutive hours was measured in 55/532 (10%) infants and the primary outcome was recorded in 25 patients. The association between a UO threshold <1.0 mL/kg/hour and the primary outcome was found marginally significant (crude OR 1.80, 95% CI 1.02 to 3.16, p=0.04). The primary outcome was recorded in 112/242 (46%) patients with a UO <2.0 mL/kg/hour and only 64/290 (22%) patients with a UO ≥2.0 mL/kg/hour (p<0.001). This UO threshold was found significantly associated with the primary outcome (crude OR 3.1, 95% CI 2.1 to 4.7, p<0.001), an association confirmed using a multivariate logistic regression model including baseline covariates (adjusted OR 3.7, 95% CI 2.2 to 6.4, p<0.001).

CONCLUSION

A UO <2 mL/kg/hour over 24 hours between postnatal day 1 and day 7 strongly predicts neonatal mortality or severe morbidities in very preterm infants.

Neonatal AKI: An update

Neonatal acute kidney injury (AKI) is a common complication, especially in the neonatal intensive care unit, that is associated with long term consequences and poor outcomes. Early detection and treatment is critical. Currently, neonatal AKI is defined with urinary markers and serum creatinine, with limitations on early detection and individual treatment. There have been numerous biomarkers and risk factor scores that have been studied for their ability to predict neonatal AKI. To move towards personalized medicine, neonatal AKI must be categorized into phenotypes and subphenotypes that fully encapsulate the diverse causes and specific treatments. This review aims to advance our understanding of neonatal AKI detection through the use of biomarkers, subphenotypes, and phenotypes to move towards personalized treatment strategies.

Case of iatrogenic neonatal acute kidney injury requiring dialysis and review of literature

A full-term male baby was administered furosemide and enalapril for treatment of cardiac failure secondary to a ventricular septal defect. He also received piperacillin-tazobactam and amikacin for 7 days for suspected early-onset neonatal sepsis. He developed anuria and raised creatinine and was referred with acute kidney injury (AKI)-neonatal KDIGO (Kidney Disease Improving Global Outcomes) stage 3 on day 20. Urine output and renal parameters improved after discontinuing drugs and peritoneal dialysis. This case report highlights the importance of serial monitoring of kidney function tests while using nephrotoxic drugs and ensuring correct dosage and titration. In the early stages, AKI can be treated with conservative therapy but once established, renal replacement therapy might be required. It can also lead to chronic kidney disease.

Frequency of Acute Kidney Injury and Association With Mortality Among Extremely Preterm Infants

IMPORTANCE

Neonatal acute kidney injury (AKI) is common and associated with morbidity and mortality. The temporal relationship between AKI and critical illness, as well as the frequency of AKI definition components (urine output and serum creatinine [sCr] concentration change), are unknown in extremely low-birth-weight (ELBW) (<1000 g), extremely preterm (<29 weeks' completed gestational age [GA]) infants.

OBJECTIVE

To measure the frequency of AKI from birth to death or discharge with attention to the definition components as well as the temporal relationship of AKI to critical illness and death.

DESIGN, SETTING, AND PARTICIPANTS

A single-center, multiyear, retrospective cohort study was conducted at an academic level IV neonatal intensive care unit between January 1, 2012, and January 1, 2020. Participants included inborn ELBW and infants at 22 to 28 weeks' completed GA with confirmed congenital anomalies who survived 12 hours or more.

EXPOSURES

Extremely preterm birth and ELBW.

MAIN OUTCOMES AND MEASURES

The primary outcome was AKI frequency. The timing, severity, and criteria for AKI were measured. The temporal relationship between AKI, organ dysfunction, and outcomes were quantified using odds ratios (ORs), logistic regression, and Shapley Additive Explanations. Acute kidney injury recognition, imaging, pediatric nephrology consultation, and follow-up were determined.

RESULTS

A total of 436 infants (52% male; 44% Black) met the inclusion criteria (median BW, 725 g; median GA, 25.7 wk). Acute kidney injury was common in the first week of life (44%), primarily based on the change in the sCr concentration criterion (88%), and negatively associated with GA (OR, 0.69; 95% CI, 0.60-0.78), but positively associated with antecedent critical illness (OR, 1.17; 95% CI, 1.12-1.23), severe intraventricular hemorrhage (OR, 1.86; 95% CI, 1.12-3.08), late-onset sepsis (OR, 1.03; 95% CI, 1.02-1.03), and mortality (OR, 2.77; 95% CI, 1.63-4.72). Acute kidney injury had negligible clinical contribution to death within the model (Shapley Additive Explanation, <0.5% change to outcome) relative to antecedent patient-concentration organ dysfunction (6%-15% change). Among infants with severe AKI, recognition (32%), nephrology inpatient consultation (16%), and outpatient follow-up (9%) were not common.

CONCLUSIONS AND RELEVANCE

In this cohort study of ELBW infants, AKI was common in the first week of life, inversely associated with GA, and followed organ (primarily cardiovascular) dysfunction. Acute kidney injury considered as the primary pathway to mortality was rare, and amelioration of AKI to modify death was not well supported.

Predictors of Death in Patients with Neonatal Sepsis in a Peruvian Hospital

Reducing neonatal mortality is a global challenge. This study’s objective was to determine the predictors of mortality in patients with neonatal sepsis. The study was a retrospective cohort study in a Peruvian hospital from January 2014 to April 2022. Neonates diagnosed with sepsis were included. To find predictors of mortality, we used Cox proportional regression models. We evaluated 288 neonates with sepsis; the median birth weight and hospitalization time were 3270 g and seven days, respectively. During follow-up, 18.4% did not survive, and the most common complications were jaundice (35.42%), respiratory distress syndrome (29.51%), and septic shock (12.5%). The most isolated bacteria were Klebsiella pneumoniae. The risk factors associated with higher mortality were prematurity (aHR = 13.92; 95% CI: 1.71−113.51), platelets <150,000 (aHR = 3.64; 1.22−10.88), creatinine greater than 1.10 (aHR = 3.03; 1.09−8.45), septic shock (aHR = 4.41; 2.23−8.74), and admission to IMV (aHR = 5.61; 1.86−16.88), On the other hand, breastfeeding was associated with a lower risk of death (aHR = 0.25; 0.13−0.48). In conclusion, we report a high incidence of death and identify clinical (prematurity, septic shock, admission to IMV) and laboratory characteristics (elevated creatinine and thrombocytopenia) associated with higher mortality in patients with neonatal sepsis. Breastfeeding was a factor associated with survival in these patients.