Baby NINJA (Nephrotoxic Injury Negated by Just-in-Time Action): Reduction of Nephrotoxic Medication-Associated Acute Kidney Injury in the Neonatal Intensive Care Unit

Use of urine neutrophil gelatinase-associated lipocalin for nephrotoxic medication acute kidney injury screening in neonates

BACKGROUND

Daily serum creatinine monitoring protocols for acute kidney injury (AKI) are invasive and may lead to surveillance resistance. We aimed to understand if use of urine neutrophil gelatinase-associated lipocalin (uNGAL) could increase high-risk nephrotoxic medication (NTMx) associated AKI screening adherence in neonates.

METHODS

Statistical process control methods prior to and post implementation were trended. The primary outcome, screening adherence, was defined as either daily serum creatinine or uNGAL assessment through 2 days post high-risk NTMx exposure.

RESULTS

1291 monitoring days from the pre-implementation era (4/2020-6/2021) were compared to1377 monitoring days from the post-era (6/2021-10/2022). AKI screening adherence increased (81 to 92%) following implementation of optional uNGAL screening. Urine NGAL accounted for 35% of screening obtained. Use of uNGAL resulted in a 40% reduction in blood sampling for serum creatinine.

CONCLUSIONS

Incorporation of uNGAL as a complementary screening tool to serum creatinine demonstrated sustained increased AKI surveillance in our Baby NINJA monitoring program.

Advocating for the inclusion of kidney health outcomes in neonatal research: best practice recommendations by the Neonatal Kidney Collaborative

Acute kidney injury (AKI) occurs in nearly 30% of sick neonates. Chronic kidney disease (CKD) can be detected in certain populations of sick neonates as early as 2 years. AKI is often part of a multisystem syndrome that negatively impacts developing organs resulting in short- and long-term pulmonary, neurodevelopmental, and cardiovascular morbidities. It is critical to incorporate kidney-related data into neonatal clinical trials in a uniform manner to better understand how neonatal AKI or CKD could affect an outcome of interest. Here, we provide expert opinion recommendations and rationales to support the inclusion of short- and long-term neonatal kidney outcomes using a tiered approach based on study design: (1) observational studies (prospective or retrospective) limited to data available within a center's standard practice, (2) observational studies involving prospective data collection where prespecified kidney outcomes are included in the design, (3) interventional studies with non-nephrotoxic agents, and (4) interventional studies with known nephrotoxic agents. We also provide recommendations for biospecimen collection to facilitate ancillary kidney specific research initiatives. This approach balances the costs of AKI and CKD ascertainment with knowledge gained. We advocate that kidney outcomes be included routinely in neonatal clinical study design. Consistent incorporation of kidney outcomes across studies will increase our knowledge of neonatal morbidity.

Post-natal steroid exposure in very low birthweight neonates and associations with acute kidney injury

OBJECTIVE

The relationship between adrenal insufficiency (AI), post-natal steroids (PNS) and neonatal acute kidney injury (AKI) remains understudied. We investigated associations between PNS and AKI in very low birthweight (VLBW) neonates, hypothesizing PNS is associated with reduced AKI.

STUDY DESIGN

We conducted a single-center retrospective review of VLBW infants comparing those with and without PNS exposure. Associations between PNS exposure and AKI were evaluated using generalized linear mixed-modeling adjusted for confounders.

RESULT

Of 567 neonates, 97 (17.1%) were exposed to PNS and 130 (22.9%) experienced AKI. Infants with PNS had lower gestational age, birthweight, Apgar scores, and experienced more AI versus those without PNS (all p < 0.05). PNS was associated with AKI (aRR 1.72, 95% CI 1.09-2.72) though hydrocortisone alone was not.

CONCLUSION

PNS exposure, but not hydrocortisone alone, is associated with increased AKI in VLBW neonates. Further analysis is needed to investigate the role of AI and AKI.

Contrast Media in Children: Ten Important Concepts on Administration, Applications, Complications, and Environmental Considerations, From the AJR Special Series on Contrast Media

Contrast media are an indispensable adjunct to pediatric imaging. The most common include iodine-based contrast media for CT and fluoroscopy, gadolinium-based contrast media and iron-oxide nanoparticles for MRI, and microbubbles for ultrasound. Although many of the considerations in the routine use of contrast media in infants and children (relating for example to renal function, allergic-like reactions, GBCM deposition, and extravasations) are similar to considerations in adult patients, some important differences exist. These variances are often age-dependent and require an appreciation of pediatric physiology for safe and effective clinical practice. This article highlights ten concepts relating to contrast media administration for diagnostic imaging in children that are important for radiologists and pediatricians to recognize and understand. We present contrast media classes and their use in children, discuss safety concerns and complications, and explore environmental impacts.

Preterm Birth and Kidney Health: From the Womb to the Rest of Life

Chronic kidney disease (CKD) is a widespread condition often resulting from multiple factors, including maternal influences. These risk factors not only heighten the likelihood of developing CKD but increase the risk of a preterm birth. Adverse events during nephrogenesis can disrupt kidney development, leading to a reduced number of nephrons. As survival rates for preterm infants improve, more individuals are living into adulthood, thereby elevating their risk of CKD later in life. This review aims to explore the connections between preterm birth, kidney development, and the increased risk of CKD, while proposing practical solutions for the future through a multidisciplinary approach. We examine human studies linking preterm birth to negative kidney outcomes, summarize animal models demonstrating kidney programming and reduced nephron numbers, and consolidate knowledge on common mechanisms driving kidney programming. Additionally, we discuss factors in the postnatal care environment that may act as secondary insults contributing to CKD risk, such as acute kidney injury (AKI), the use of nephrotoxic drugs, preterm nutrition, and catch-up growth. Finally, we outline recommendations for action, emphasizing the importance of avoiding modifiable risk factors and implementing early CKD screening for children born preterm. Together, we can ensure that advancements in kidney health keep pace with improvements in preterm care.

Urine Output and Acute Kidney Injury in Neonates/Younger Children: A Prospective Study of Cardiac Surgery Patients with Indwelling Urinary Catheters

Key Points

Using indwelling urinary catheters, urine output (UO) shows good performance in neonates and younger children. Using higher UO thresholds in neonates post-cardiac surgery improves discriminatory capacity for outcomes compared to neonatal Kidney Disease Improving Global Outcomes. In younger children (1–24 months), higher UO thresholds were not better than the adult Kidney Disease Improving Global Outcomes criteria.

Background

Pediatric AKI is associated with significant morbidity and mortality, yet a precise definition, especially concerning urine output (UO) thresholds, remains unproven. We evaluate UO thresholds for AKI in neonates and children aged 1–24 months with indwelling urinary catheters undergoing cardiac surgery.

Methods

A 6-year prospective cohort study (2018–2023) after cardiac surgery was conducted at a reference center in Brazil. All patients had indwelling urinary catheters up to 48 hours after surgery and at least two serum creatinine measurements, including one before surgery. The main objective of this study was to determine the optimal UO thresholds for AKI definition and staging in neonates and younger children compared with the currently used criteria—neonatal and adult Kidney Disease Improving Global Outcomes (KDIGO) definitions. The outcome was a composite of severe AKI (stage 3 AKI diagnosed by the serum creatinine criterion only), KRT, or hospital mortality.

Results

The study included 1024 patients: 253 in the neonatal group and 772 in the younger children group. In both groups, the lowest UO at 24 hours as a continuous variable had good discriminatory capacity for the composite outcome (area under the curve-receiver operating characteristic 0.75 [95% confidence interval, 0.70 to 0.81] and 0.74 [95% confidence interval, 0.68 to 0.79]). In neonates, the best thresholds were 3.0, 2.0, and 1.0 ml/kg per hour, and in younger children, the thresholds were 1.8, 1.0, and 0.5 ml/kg per hour. These values were used for modified AKI staging for each age group. In neonates, this modified criterion was associated with the best discriminatory capacity (area under the curve-receiver operating characteristic 0.74 [0.67 to 0.80] versus 0.68 [0.61 to 0.75], P < 0.05) and net reclassification improvement in comparison with the neonatal KDIGO criteria. In younger children, the modified criteria had good discriminatory capacity but were comparable with the adult KDIGO criteria, and the net reclassification improvement was near zero.

Conclusions

Using indwelling catheters for UO measurements, our study reinforced that the current KDIGO criteria may require adjustments to better serve the neonate population. In addition, using the UO criteria, we validated the adult KDIGO criteria in children aged 1–24 months.

Drug related adverse event assessment in neonates in clinical trials and clinical care

INTRODUCTION

Assessment of drug-related adverse events is essential to fully understand the benefit-risk balance of any drug exposure, weighing efficacy versus safety. This is needed for both drug labeling and clinical decision-making. Assessment is based on seriousness, severity and causality, be it more difficult to apply in neonates. Adverse event detection or prevention in the neonatal clinical setting is also more complicated because of polypharmacy, and off-label or unlicensed pharmacotherapy.

AREAS COVERED

Tools became available to assess severity and causality of adverse events in neonates recruited in clinical trials. The first version of the Neonatal Adverse Event severity score (NAESS) reduced the inter-observer variability. Causality tools like the Naranjo score were also tailored to neonates. These tools are also instrumental to support proactive pharmacovigilance in clinical care, while multidisciplinary care teams and computerized pharmacovigilance using advanced data analysis, like machine learning are emerging approaches to develop effective decision strategies.

EXPERT OPINION

All stakeholders involved in development of medicines or its clinical use should be aware of the limitations of the currently available assessment tools. Extension and optimization of these tools, advanced data analysis approaches, and capturing the variability in time-dependent physiology are warranted to improve pharmacovigilance in neonates.

ADVANCE: a biomedical informatics approach to investigate acute kidney injury in infants

BACKGROUND

Acute kidney injury (AKI) occurs in up to half of infants admitted to the neonatal intensive care unit (NICU) and is associated with increased risks of death and more days of mechanical ventilation, hospitalization, and vasopressor drug support. Our objective was to build a granular relational database to study the impact that AKI has on infants admitted to Level-IV NICUs.

METHODS

A relational database was created by linking data from the Children's Hospitals Neonatal Database with AKI-focused data from electronic health records from 9 centers.

RESULTS

The current cohort consists of 24,870 infants with a median (IQR) gestational age of birth of 37 weeks (32 weeks, 39 weeks), and a median birth weight of 2.720 kg (1.750 kg, 3.310 kg). There was a male predominance with 14,214 (57%) males. In all, 2434 (9.8%) of the mothers were of Hispanic ethnicity. The maternal race breakdown of the cohort was as follows: 741 (3.0%) Asian, 5911 (24%) Black, and 14,945 (60%) White. Overall mortality was 5.8%.

CONCLUSION

The ADVANCE relational database is an innovative research tool to rigorously study the epidemiology of AKI in a large national cohort of infants admitted to Level-IV NICUs involved in the Children's Hospital Neonatal Consortium.

IMPACT

We used a biomedical informatics approach to build a relational database to study acute kidney injury in infants. We highlight our methodology linking Children's Hospital Neonatal Consortium and electronic health record data from nine neonatal intensive care units. The ADVANCE relational database is a granular and innovative research tool to study risk factors and in-hospital outcomes of acute kidney injury and mortality in a vulnerable patient population.

Utilizing electronic medical records alert to improve documentation of neonatal acute kidney injury

BACKGROUND

Neonatal acute kidney injury (AKI) is a common yet underdiagnosed condition in neonates with significant implications for long-term kidney health. Lack of timely recognition and documentation of AKI contributes to missed opportunities for nephrology consultation and follow-up, potentially leading to adverse outcomes.

METHODS

We conducted a quality improvement (QI) project to address this by incorporating an automated real-time electronic medical record (EMR)-AKI alert system in the Neonatal Intensive Care Unit (NICU) at Le Bonheur Children's Hospital. Our primary objective was to improve documentation of neonatal AKI (defined as serum creatinine (SCr) > 1.5 mg/dL) by 25% compared to baseline levels. The secondary goal was to increase nephrology consultations and referrals to the neonatal nephrology clinic. We designed an EMR-AKI alert system to trigger for neonates with SCr > 1.5 mg/dL, automatically adding AKI diagnosis to the problem list. This prompted physicians to consult nephrology, refer neonates to the nephrology clinic, and consider medication adjustments.

RESULTS

Our results demonstrated a significant improvement in AKI documentation after implementing the EMR-AKI alert, reaching 100% compared with 7% at baseline (p < 0.001) for neonates with SCr > 1.5 mg/dL. Although the increase in nephrology consultations was not statistically significant (p = 0.5), there was a significant increase in referrals to neonatal nephrology clinics (p = 0.005).

CONCLUSIONS

Integration of an EMR alert system with automated documentation offers an efficient and economical solution for improving neonatal AKI diagnosis and documentation. This approach enhances healthcare provider engagement, streamlines workflows, and supports QI. Widespread adoption of similar approaches can lead to improved patient outcomes and documentation accuracy in neonatal AKI care.

Pharmacovigilance of nephrotoxic drugs in neonates: the Pottel method for acute kidney injury detection in ELBW neonates

BACKGROUND

Extremely low birth weight (ELBW) neonates (birth weight ≤ 1000 g) are at high risk to develop drug-induced acute kidney injury (AKI). However, we lack a pragmatic detection tool to capture their time-dependent (patho)physiologic serum creatinine (Scr) patterns. Pottel et al. suggested rescaling Scr by dividing Scr with the mean Scr value of the age- and sex-specific reference population. We explored if this Pottel method can detect drug-related nephrotoxicity in ELBW neonates.

METHODS

A previously reported dataset on Scr changes in ELBW neonates exposed to ibuprofen, amikacin, or vancomycin was updated to calculate Pottel scores for every available Scr value in the first 28 postnatal days. We hereby used previously published postnatal age-specific 50th centile values in an ELBW population. Linear mixed models were applied, analyzing Pottel scores as response variable and continuous time (day), drug exposure, and interaction thereof in the explanatory model.

RESULTS

Serum creatinine (n = 3231) observations in 201 ELBW neonates were collected. A statistically significant rise of Pottel scores was observed with ibuprofen starting from postnatal day 4. In addition, a cumulative effect of treatment with mean Pottel scores on day 0 of 1.020 and on day 3 during treatment of 1.106 (95% CI 1.068-1.145, p < 0.001) was observed, corrected for effect of antibiotics. Antibiotic administrations showed a small but statistically significant difference up to postnatal day 5.

CONCLUSIONS

As rescaled Scr biomarker, the Pottel method showed a clear association with ibuprofen-exposed ELBW neonates, suggesting its applicability as a pragmatic bedside alternative tool to assess nephrotoxicity.

A pilot clinical risk model to predict polymyxin-induced nephrotoxicity: a real-world, retrospective cohort study

OBJECTIVES

Polymyxin-induced nephrotoxicity (PIN) is a major safety concern and challenge in clinical practice, which limits the clinical use of polymyxins. This study aims to investigate the risk factors and to develop a scoring tool for the early prediction of PIN.

METHODS

Data on critically ill patients who received intravenous polymyxin B or colistin sulfate for over 24 h were collected. Logistic regression with the least absolute shrinkage and selection operator (LASSO) was used to identify variables that are associated with outcomes. The eXtreme Gradient Boosting (XGB) classifier algorithm was used to further visualize factors with significant differences. A prediction model for PIN was developed through binary logistic regression analysis and the model was assessed by temporal validation and external validation. Finally, a risk-scoring system was developed based on the prediction model.

RESULTS

Of 508 patients, 161 (31.6%) patients developed PIN. Polymyxin type, loading dose, septic shock, concomitant vasopressors and baseline blood urea nitrogen (BUN) level were identified as significant predictors of PIN. All validation exhibited great discrimination, with the AUC of 0.742 (95% CI: 0.696-0.787) for internal validation, of 0.708 (95% CI: 0.605-0.810) for temporal validation and of 0.874 (95% CI: 0.759-0.989) for external validation, respectively. A simple risk-scoring tool was developed with a total risk score ranging from -3 to 4, corresponding to a risk of PIN from 0.79% to 81.24%.

CONCLUSIONS

This study established a prediction model for PIN. Before using polymyxins, the simple risk-scoring tool can effectively identify patients at risk of developing PIN within a range of 7% to 65%.

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 Neonatal Intensive Care Unit: Epidemiology, Diagnosis and Risk Factors

Acute kidney injury (AKI) is associated with long-term consequences and poor outcomes in the neonatal intensive care unit. Its precocious diagnosis represents one of the hardest challenges in clinical practice due to the lack of sensitive and specific biomarkers. Currently, neonatal AKI is defined with urinary markers and serum creatinine (sCr), with limitations in early detection and individual treatment. Biomarkers and risk factor scores were studied to predict neonatal AKI, to early identify the stage of injury and not the damage and to anticipate late increases in sCr levels, which occurred when the renal function already began to decline. Sepsis is the leading cause of AKI, and sepsis-related AKI is one of the main causes of high mortality. Moreover, preterm neonates, as well as patients with post-neonatal asphyxia or after cardiac surgery, are at a high risk for AKI. Critical patients are frequently exposed to nephrotoxic medications, representing a potentially preventable cause of AKI. This review highlights the definition of neonatal AKI, its diagnosis and new biomarkers available in clinical practice and in the near future. We analyze the risk factors involving patients with AKI, their outcomes and the risk for the transition from acute damage to chronic kidney disease.

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.

Acute kidney injury surveillance in the high-risk neonatal population following implementation of creatinine screening protocol

AIM

Acute kidney injury (AKI) in neonates is associated with longer hospital stays and higher mortality rates. However, there is significant variability in prevalence rates of AKI and the true burden is incompletely understood. In November 2020, the University of Iowa Stead Family Children's Hospital Neonatal Intensive Care Unit implemented a creatinine screening protocol to enhance kidney function monitoring. We sought to evaluate adherence to the protocol to determine if increased surveillance led to increased detection of AKI events.

METHODS

A retrospective chart review was conducted for neonates born at <30 weeks' gestation admitted between 2015 and 2020. We reviewed 100 charts in both the pre (2015-2016) and post (2020-2021) implementation era of the AKI surveillance protocol. AKI was defined according to neonatal modified KDIGO criteria.

RESULTS

Following implementation of the protocol, neonates were significantly more likely to have creatinine checked (p < 0.001). Serum creatinine was drawn according to protocol guidelines 68% of the time, and 42% of patients (34/82) had an 80% or higher adherence to the protocol. There was a significant increase in detection of AKI in the post-protocol cohort (13/82, incidence of 16%) compared to the pre-protocol cohort (5/83, incidence of 6%), (p = 0.047).

CONCLUSION

The implementation of a serum creatinine screening protocol increased the frequency of creatinine draws and detection of AKI.

Fluid and electrolyte management in the neonate and what can go wrong

PURPOSE OF REVIEW

This review highlights recent advances in understanding fluid and electrolyte homeostasis during the newborn period, including heightened recognition of fluid overload and acute kidney injury contributing to poor clinical outcomes. Particular attention is given towards the care of extremely preterm infants.

RECENT FINDINGS

Emerging data demonstrate (i) disproportionally large transepidermal water loss in the extremely preterm population, (ii) the relationship between postnatal weight loss (negative fluid balance) and improved outcomes, (iii) the frequency and negative effects of dysnatremias early in life, (iv) the role of sodium homeostasis in optimizing postnatal growth, and (v) the deleterious effects of fluid overload and acute kidney injury.

SUMMARY

As clinicians care for an increasing number of preterm infants, understanding progress in approaches to fluid and electrolyte management and avoidance of fluid overload states will improve the care and outcomes of this vulnerable population. Further translational and clinical studies are needed to address remaining knowledge gaps and improve current approaches to fluid and electrolyte management.

Recent Advances in Kidney Replacement Therapy in Infants: A Review

Kidney replacement therapy (KRT) is used to treat children and adults with acute kidney injury (AKI), fluid overload, kidney failure, inborn errors of metabolism, and severe electrolyte abnormalities. Peritoneal dialysis and extracorporeal hemodialysis/filtration can be performed for different durations (intermittent, prolonged intermittent, and continuous) through either adaptation of adult devices or use of infant-specific devices. Each of these modalities have advantages and disadvantages, and often multiple modalities are used depending on the scenario and patient-specific needs. Traditionally, these therapies have been challenging to deliver in infants due the lack of infant-specific devices, small patient size, required extracorporeal volumes, and the risk of hemodynamic stability during the initiation of KRT. In this review, we discuss challenges, recent advancements, and optimal approaches to provide KRT in hospitalized infants, including a discussion of peritoneal dialysis and extracorporeal therapies. We discuss each specific KRT modality, review newer infant-specific devices, and highlight the benefits and limitations of each modality. We also discuss the ethical implications for the care of infants who need KRT and areas for future research.

Recurrent neonatal acute kidney injury: incidence, predictors, and outcomes in the neonatal intensive care unit

OBJECTIVE

Determine recurrent neonatal acute kidney injury (rAKI) incidence, risk factors, and associated outcomes.

STUDY DESIGN

Single-center retrospective cohort of neonates admitted to the NICU 1/1/20-6/30/21. Comparisons were made between those with no AKI, single AKI episode (sAKI), and rAKI. Multivariable linear and logistic regression models were used to assess associations between rAKI and length of mechanical ventilation (LMV), length of hospitalization stay (LOS), mortality, and hypertension (HTN) at discharge.

RESULTS

The incidence of AKI in the cohort of 869 infants was 19%: 705 (81%) no AKI, 100 (12%) sAKI, 64 (7%) rAKI. Both sAKI and rAKI were independently associated with longer LMV and LOS. sAKI was independently associated with almost 4x higher odds of mortality than rAKI.

CONCLUSION

In this single center cohort of neonates, sAKI independently predicts mortality, however rAKI is independently associated with increased LMV and LOS suggesting rAKI is clinically important and warrants further study.

Advances in pediatric acute kidney injury pharmacology and nutrition: a report from the 26th Acute Disease Quality Initiative (ADQI) consensus conference

BACKGROUND

In the past decade, there have been substantial advances in our understanding of pediatric AKI. Despite this progress, large gaps remain in our understanding of pharmacology and nutritional therapy in pediatric AKI.

METHODS

During the 26th Acute Disease Quality Initiative (ADQI) Consensus Conference, a multidisciplinary group of experts reviewed the evidence and used a modified Delphi process to achieve consensus on recommendations for gaps and advances in care for pharmacologic and nutritional management of pediatric AKI. The current evidence as well as gaps and opportunities were discussed, and recommendations were summarized.

RESULTS

Two consensus statements were developed. (1) High-value, kidney-eliminated medications should be selected for a detailed characterization of their pharmacokinetics, pharmacodynamics, and pharmaco-"omics" in sick children across the developmental continuum. This will allow for the optimization of real-time modeling with the goal of improving patient care. Nephrotoxin stewardship will be identified as an organizational priority and supported with necessary resources and infrastructure. (2) Patient-centered outcomes (functional status, quality of life, and optimal growth and development) must drive targeted nutritional interventions to optimize short- and long-term nutrition. Measures of acute and chronic changes of anthropometrics, body composition, physical function, and metabolic control should be incorporated into nutritional assessments.

CONCLUSIONS

Neonates and children have unique metabolic and growth parameters compared to adult patients. Strategic investments in multidisciplinary translational research efforts are required to fill the knowledge gaps in nutritional requirements and pharmacological best practices for children with or at risk for AKI.

Duration of Simultaneous Exposure to High-Risk and Lower-Risk Nephrotoxic Antimicrobials in the Neonatal Intensive Care Unit (NICU) and Future Adolescent Kidney Health

OBJECTIVE

To determine whether greater duration of simultaneous exposure to antimicrobials with high nephrotoxicity risk combined with lower-risk antimicrobials (simultaneous exposure) in the neonatal intensive care unit (NICU) is associated with worse later kidney health in adolescents born preterm with very low birth weight (VLBW).

STUDY DESIGN

Prospective cohort study of participants born preterm with VLBW (<1500 g) as singletons between January 1, 1992, and June 30, 1996. We defined simultaneous exposure as a high-risk antimicrobial, such as vancomycin, administered with a lower-risk antimicrobial on the same date in the NICU. Outcomes were serum creatinine, estimated glomerular filtration rate (eGFR), and first-morning urine albumin-creatinine ratio (ACR) at age 14 years. We fit multivariable linear regression models with days of simultaneous exposure and days of nonsimultaneous exposure as main effects, adjusting for gestational age, birth weight, and birth weight z-score.

RESULTS

Of the 147 out of 177 participants who had exposure data, 97% received simultaneous antimicrobials for mean duration 7.2 days (SD 5.6). No participant had eGFR <90 ml/min/1.73 m2. The mean ACR was 15.2 mg/g (SD 38.7) and 7% had albuminuria (ACR >30 mg/g). Each day of simultaneous exposure was associated only with a 1.04-mg/g higher ACR (95% CI 1.01 to 1.06).

CONCLUSIONS

Despite frequent simultaneous exposure to high-risk combined with lower-risk nephrotoxic antimicrobials in the NICU, there were no clinically relevant associations with worse kidney health identified in adolescence. Although future studies are needed, these findings may provide reassurance in a population thought to be at increased risk of chronic kidney disease.

The Utility of Urinary NGAL as an Alternative for Serum Creatinine to Detect Acute Kidney Injury in Infants Exposed to Nephrotoxic Medications in the Neonatal Intensive Care Unit

INTRODUCTION

Nephrotoxic medication (NTM) exposure is commonly associated with acute kidney injury (AKI) in the neonatal intensive care unit (NICU). Baby Nephrotoxic Injury Negated by Just-in-Time Action (NINJA) is a quality improvement program that assesses for AKI in those exposed to NTM with daily serum creatinine (SCr) levels. However, blood draws for SCr are invasive and have clinical disadvantages. Urinary neutrophil gelatinase-associated lipocalin (uNGAL) is a promising indicator of AKI. We tested the hypothesis that uNGAL could reliably screen for NTM-AKI in the Baby NINJA program.

METHODS

This two-center prospective study screened 174 NICU subjects, of whom 148 met screening criteria from January 29, 2019, to September 18, 2020. Daily SCr and urine samples were obtained for up to 7 days of NTM exposure plus 2 days after exposure ended or end of AKI. AKI was defined by a SCr rise of 50% from baseline. The highest uNGAL obtained was evaluated to determine its relationship to the diagnosis of AKI. Logistic regression models were used to determine optimal uNGAL cutoffs.

RESULTS

The negative predictive value of a uNGAL value ≥250 ng/mL was 96.8% (95% CI = 93.3-100%). Urine NGAL ≥400 ng/mL demonstrated the highest ROC-AUC value of 0.72 with a positive likelihood risk for AKI of 2.76 (1.39-4.13).

DISCUSSION/CONCLUSION

We propose that uNGAL could be used to screen for NTM-AKI and thus replace many blood draws needed in those exposed to NTM. The ideal uNGAL threshold requires further investigation in infants.

Preceding risks and mortality outcomes of different neonatal acute kidney injury in preterm infants

BACKGROUND

The aim of the study was to examine preceding risks and mortality outcomes of oliguric and non-oliguric acute kidney injury (AKI) in very preterm infants.

METHODS

Infants born ≤30 weeks' gestation were included. AKI was diagnosed based on neonatal Kidney Disease: Improving Global Outcomes criteria and was classified as oliguric and non-oliguric according to the urine-output criteria. We used modified Poisson and Cox proportional-hazards models for statistical comparisons.

RESULTS

Of 865 enrolled infants (gestational age 27.2 ± 2.2 weeks and birth weight 983 ± 288 gm), 204 (23.6%) developed AKI. Before AKI, the oliguric AKI group had significantly higher prevalence of small-for-gestational age (p = 0.008), lower 5-min Apgar score (p = 0.009) and acidosis (p = 0.009) on admission, and hypotension (p = 0.008) and sepsis (p = 0.001) during admission than the non-oliguric AKI group. Oliguric (adjusted risk ratio 3.58, 95% CI 2.33-5.51; adjusted hazard ratio 4.93, 95% CI 3.14-7.72) instead of non-oliguric AKI had significantly higher mortality risks than no AKI. Oliguric AKI showed significantly higher mortality risks than non-oliguric AKI, irrespective of serum creatinine and severity of AKI.

CONCLUSIONS

Categorizing AKI as oliguric and non-oliguric was crucial because of the distinct preceding risks and mortality outcomes of these two types of AKI in very preterm neonates.

IMPACT

The differences of the underlying risks and prognosis between oliguric and non-oliguric AKI in very preterm infants remain unclear. We found that oliguric AKI, but not non-oliguric AKI, carries higher mortality risks than infants without AKI. Oliguric AKI possessed higher mortality risks than non-oliguric AKI, irrespective of concomitant serum creatinine elevation and severe AKI. Oliguric AKI is more associated with prenatal small-for-the-gestational age and perinatal and postnatal adverse events, while non-oliguric AKI is associated with nephrotoxins exposures. Our finding highlighted the importance of oliguric AKI and is helpful in developing future protocol in neonatal critical care.

Acute kidney injury in children: incidence, awareness and outcome-a retrospective cohort study

The primary objective was to determine the epidemiologic influence of AKI awareness among physicians in a mixt paediatric population, including neonates. This single-centre, multiyear, observational retrospective study included all admitted patients between first of July 2014 and 31 December 2021. AKI was identified in 2194 patients out of the 128,036 hospital admissions with 129,936 serum creatinine measurements. Matching comparisons were used between AKI aware and AKI non-aware patients. The overall incidence of AKI was 1.65%. Stage 1 was identified in 24.24% of the AKI cases, stage 2 in 31.03% and stage 3 in 44.71%. The most prevalent cause of AKI was represented by prerenal AKI in 85.64% of the cases, followed by 12.16% renal causes respectively 2.18% postrenal causes. Exposure to sepsis, critical illness, hypovolemic shock and mechanical ventilation increased mortality by 2.09, 4.69, 4.64- and 4.93-times (p = 0.001). Cancer and heart failure increased mortality by 4.22 (p < 0.001) respectively 2.17 times (p = 0.001). The presence of AKI increased mortality by 79.11 times while only half of the AKI associated deaths were recognized by physicians. AKI increased hospitalization more than 4 times the average stay. AKI awareness was dependent of lower age and severity. Also, awareness increased mortality and prolonged hospitalization. 1 in 3 neonates and 1 in 4 children were AKI aware. The physician's awareness of AKI diagnosis is in general low due to lack of appliance of current guidelines in exploring exposures and susceptibilities for AKI screening.

Early recognition and prevention of acute kidney injury in hospitalised children

Acute kidney injury is common in hospitalised children and is associated with poor patient outcomes. Once acute kidney injury occurs, effective therapies to improve patient outcomes or kidney recovery are scarce. Early identification of children at risk of acute kidney injury or at an early injury stage is essential to prevent progression and mitigate complications. Paediatric acute kidney injury is under-recognised by clinicians, which is a barrier to optimisation of inpatient care and follow-up. Acute kidney injury definitions rely on functional biomarkers (ie, serum creatinine and urine output) that are inadequate, since they do not account for biological variability, analytical issues, or physiological responses to volume depletion. Improved predictive tools and diagnostic biomarkers of kidney injury are needed for earlier detection. Novel strategies, including biomarker-guided care algorithms, machine-learning methods, and electronic alerts tied to clinical decision support tools, could improve paediatric acute kidney injury care. Clinical prediction models should be studied in different paediatric populations and acute kidney injury phenotypes. Research is needed to develop and test prevention strategies for acute kidney injury in hospitalised children, including care bundles and therapeutics.

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.

Implementation Strategies for Baby NINJA (Nephrotoxic Injury Negated by Just-in-Time Action) to Prevent Neonatal Medication-Induced Kidney Injury

Acute kidney injury (AKI) is a common complication among patients admitted to the neonatal intensive care unit. Nephrotoxic medications (NTMs) are known to increase the incidence of AKI, but the use of these -medications is often unavoidable. Baby NINJA (Nephrotoxic Injury Negated by Just-in-Time Action) is a -quality improvement (QI) project that may be implemented at individual institutions and aims to systematically identify AKI in neonates and infants receiving NTMs. The purpose of this review is to describe nephrotoxic AKI in the neonatal population, introduce the Baby NINJA QI project and its potential to reduce neonatal AKI, and outline strategies for effective implementation of Baby NINJA.

Neonatal nephrotoxic medication exposure and early acute kidney injury: results from the AWAKEN study

BACKGROUND

We aimed to describe nephrotoxic medication exposure and investigate associations between exposure and acute kidney injury (AKI) in the neonatal intensive care unit during the first postnatal week.

DESIGN/METHODS

Secondary analysis of the AWAKEN cohort. We evaluated nephrotoxic medication exposure during the first postnatal week and associations with AKI using time-varying Cox proportional hazard regressions models. Nephrotoxic medication exposure categories were defined as: no nephrotoxic medication, nephrotoxic medications excluding aminoglycosides, aminoglycoside alone, and aminoglycoside and another nephrotoxic medication.

RESULTS

Of 2162 neonates, 1616 (74.7%) received ≥1 nephrotoxic medication. Aminoglycoside receipt was most common (72%). AKI developed in 211(9.8%) neonates and was associated with a nephrotoxic medication exposure (p < 0.01). Nephrotoxic medication exposures including a nephrotoxic medication excluding aminoglycoside (aHR 3.14, 95% CI 1.31-7.55) and aminoglycoside and  another nephrotoxic medication (aHR 4.79, 95% CI 2.19-10.50) were independently associated with AKI and severe AKI (stage 2/3), respectively.

CONCLUSIONS

Nephrotoxic medication exposure in critically ill infants is common during the first postnatal week. Specific nephrotoxic medication exposure, principally aminoglycosides with another nephrotoxic medication, are independently associated with early AKI.

Pharmacokinetics in Critically Ill Children with Acute Kidney Injury

Acute kidney injury (AKI) is a commonly encountered comorbidity in critically ill children. The coexistence of AKI disturbs drug pharmacokinetics and pharmacodynamics, leading to clinically significant consequences. This can complicate an already critical clinical scenario by causing potential underdosing or overdosing giving way to possible therapeutic failures and adverse reactions. Current available studies offer little guidance to help maneuver such complex dosing regimens and decision-making in pediatric patients as most of them are done on heterogeneous groups of adult populations. Though there are some studies on drug dosing during continuous renal replacement therapy (CRRT), their utility is in question because of the recent advances in CRRT technology. Our review aims to discuss the principles of pharmacokinetics pertinent for honing the existing practices of drug dosing in critically ill children with AKI, and the various complexities and intricate challenges involved. This in turn will provide a framework to help enable caretakers to tailor dosing regimens in complex clinical setups with further ease and precision.

Neonatal acute kidney injury during indomethacin therapy: does it predict ductal closure?

BACKGROUND

Preterm newborns are at risk for patent ductus arteriosus, and non-steroidal anti-inflammatory drugs are often used to facilitate patent ductus arteriosus closure. Acute kidney injury is common in critically ill neonates and may be caused by non-steroidal anti-inflammatory drugs. We sought to describe the incidence of acute kidney injury among preterm infants receiving indomethacin and determine whether acute kidney injury during indomethacin therapy is associated with subsequent patent ductus arteriosus closure.

METHODS

Retrospective cohort including neonates < 33 weeks gestational age, admitted to two level IIIb neonatal intensive care units between November 2016 and November 2019, who received indomethacin in the first 2 weeks of life. Acute kidney injury in the 7-day period after treatment was defined by neonatal modified Kidney Disease Improving Global Outcomes (KDIGO) criteria. Patent ductus arteriosus closure was defined clinically and/or via echocardiogram. Clinical characteristics were extracted from medical records. Association between acute kidney injury during treatment and successful closure of patent ductus arteriosus was evaluated using chi-square tests and logistic regression.

RESULTS

One hundred fifty preterm infants were included; acute kidney injury occurred in 8% (all KDIGO Stage 1). Patent ductus arteriosus closed in 52.9% of the non-acute kidney injury group and 66.7% of the acute kidney injury group (p = 0.55). Serum creatinine was checked a mean of 3.1 times in the acute kidney injury group and 2.2 times in the non-acute kidney injury group. There was no difference in survival.

CONCLUSION

We found no association between acute kidney injury during indomethacin therapy and patent ductus arteriosus closure. Paucity of serum creatinine values likely underdiagnosed acute kidney injury. Surveillance of kidney function during indomethacin therapy using more sensitive renal biomarkers may better identify infants who develop acute kidney injury in the context of non-steroidal anti-inflammatory drug use.

Nephrotoxin Exposure and Acute Kidney Injury in Adults

BACKGROUND

Rates of nephrotoxic AKI are not well described in adults due to lack of a clear definition, debate over which drugs should be considered nephrotoxins, and illness-related confounding. Nephrotoxic Injury Negated by Just-in Time Action (NINJA), a program that reduces rates of nephrotoxic AKI in pediatric populations, may be able to address these concerns, but whether NINJA can be effectively applied to adults remains unclear.

METHODS

In this retrospective cohort study conducted at the University of Iowa Hospital, we included adult patients admitted to a general hospital floor for ≥48 hours during 2019. The NINJA algorithm screened charts for high nephrotoxin exposure and AKI. After propensity score matching, Cox proportional hazard modeling was used to evaluate the relationship between nephrotoxic exposure and all-stage AKI, stage 2-3 AKI, or death. Additional analyses evaluated the most frequent nephrotoxins used in this population.

RESULTS

Of 11,311 patients, 1527 (16%) had ≥1 day of high nephrotoxin exposure. Patients with nephrotoxic exposures subsequently developed AKI in 29% of cases, and 22% of all inpatient AKI events met nephrotoxic AKI criteria. Common nephrotoxins were vancomycin, iodinated contrast dye, piperacillin-tazobactam, acyclovir, and lisinopril. After propensity score matching, Cox proportional hazard models for high nephrotoxin exposure were significantly associated with all AKI (hazard ratio [HR] 1.43, 1.19-1.72, P<0.001), stage 2-3 AKI (HR 1.78, 1.18-2.67, P=0.006), and mortality (HR 2.12, 1.09-4.11, P=0.03).

CONCLUSIONS

Nephrotoxin exposure in adults is common and is significantly associated with AKI development, including stage 2-3 AKI.

Acute Kidney Injury in Very Low Birth Weight Infants: A Major Morbidity and Mortality Risk Factor

BACKGROUND AND OBJECTIVES

Very low birth weight (VLBW) infants are at high risk of developing acute kidney injury (AKI), presumably secondary to low kidney reserves, stressful postnatal events, and drug exposures. Our study aimed to identify the prevalence, risk factors, and outcomes associated with AKI in VLBW infants.

STUDY DESIGN

Records of all VLBW infants admitted to two medical campuses between January 2019 and June 2020 were retrospectively reviewed. AKI was classified using the modified KDIGO definition to include only serum creatinine. Risk factors and composite outcomes were compared between infants with and without AKI. We evaluated the main predictors of AKI and death with forward stepwise regression analysis.

RESULTS

152 VLBW infants were enrolled. 21% of them developed AKI. Based on the multivariable analysis, the most significant predictors of AKI were the use of vasopressors, patent ductus arteriosus, and bloodstream infection. AKI had a strong and independent association with neonatal mortality.

CONCLUSIONS

AKI is common in VLBW infants and is a significant risk factor for mortality. Efforts to prevent AKI are necessary to prevent its harmful effects.

Blood pressure and kidney function in neonates and young infants with intrauterine growth restriction

BACKGROUND

Intrauterine growth restriction (IUGR) has been associated with changes in kidney anatomy, nephrogenesis and the vascular system, resulting in secondary arterial hypertension and kidney damage in adulthood. Here, we compare routine clinical and metabolic parameters between IUGR and non-IUGR study participants in the neonatal and early infant period.

METHODS

A total of 39 IUGR and 60 non-IUGR neonates were included during an 18-month study period. We compared blood pressure, serum creatinine (SCr), urea nitrogen (BUN), urinary albumin, α-1-microglobulin, transferrin, immunoglobulin G and total protein excretion in spontaneous urine normalized by urine creatinine level during the hospital stay.

RESULTS

There were no significant differences in mean values of blood pressure and urinary protein excretion between cases and controls. SCr and BUN levels were lower in the IUGR group compared to the non-IUGR group.

CONCLUSIONS

The lower levels of SCr and BUN may be attributed to lower liver and muscle mass in IUGR neonates and young infants. Biomarkers currently used in routine clinical care do not allow early postnatal prediction of higher blood pressure or worse kidney function due to IUGR, so further studies are needed. A higher resolution version of the Graphical abstract is available as Supplementary information.

Acute kidney injury post-abdominal surgery in infants: implications for prevention and management

Acute kidney injury (AKI) is common in critically ill infants and is associated with long-term sequelae including hypertension and chronic kidney disease. The etiology of AKI in infants is multifactorial. There is robust literature highlighting the risk of AKI after cardiothoracic surgery in infants. However, risk factors and outcomes for AKI in infants after abdominal surgery remains limited. This article reviews the epidemiology and association of abdominal surgery with postoperative AKI and suggests methods for AKI management and prevention. Postoperative AKI may result from hemodynamic shifts, hypoxia, exposure to nephrotoxic medications, and inflammation. Infants in the intensive care unit after intraabdominal surgeries have a unique set of risk factors that predispose them to AKI development. Prematurity, sepsis, prolonged operation time, emergent nature of the procedure, and diagnosis of necrotizing enterocolitis increase risk of AKI after intrabdominal surgeries. Prevention, early diagnosis, and management of AKI post-abdominal surgery is imperative to clinical practice. Close monitoring of urine output, serum creatinine, and fluid status is necessary in infants after abdominal surgery. A recent study suggests elevated levels of a urinary biomarker, neutrophil gelatinase-associated lipocalin (NGAL), 24 h after an abdominal procedure may improve early prediction of AKI. Identification of risk factors, avoidance of nephrotoxic medications, careful fluid balance, early detection of AKI, and maintenance of hemodynamic stability is imperative to potentially prevent and/or mitigate AKI.

Acute kidney injury and early fluid load in a retrospective cohort of neonatal sepsis

BACKGROUND

Sepsis and acute kidney injury (AKI) are associated with mortality in the newborn intensive care unit (NICU). There is a paucity of studies that describe AKI and fluid overload in neonatal sepsis and their association with mortality.

METHODS

Retrospective study of neonates with culture positive sepsis admitted to the NICU between June 2020 and June 2021 was conducted. Primary outcome was in-hospital mortality according to AKI as defined by the neonatal modified Kidney Diseases Improving Outcomes criteria. Secondary outcomes were early fluid overload and vasopressor use.

RESULTS

Thirty-three percent of neonates had AKI with sepsis, and 57% of cases were severe AKI. AKI was associated with mortality after adjusting for variables that were different between survivors and non-survivors (aOR 5.7 [95% CI 1.1-36], p = 0.04). Early fluid overload occurred in 27% of neonates who were at higher risk of having AKI with sepsis (OR 7.4 [95% CI 1.6-26.0], p = 0.01) and higher risk of mortality (aOR 17.8 [95% CI 2-7545], p = 0.02).

CONCLUSIONS

AKI and early fluid overload are associated with mortality in sepsis in our retrospective cohort. Mitigating AKI and early fluid overload in sepsis might be a fruitful strategy in reducing mortality with sepsis. A higher resolution version of the Graphical abstract is available as Supplementary information.

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.

Subphenotypes of acute kidney injury in children

PURPOSE OF REVIEW

The purpose of this review is to describe acute kidney injury (AKI) phenotypes in children.

RECENT FINDINGS

AKI is a heterogenous disease that imposes significant morbidity and mortality on critically ill and noncritically ill patients across the age spectrum. As our understanding of AKI and its association with outcomes has improved, it is becoming increasingly apparent that there are distinct AKI subphenotypes that vary by cause or associated conditions. We have also learned that severity, duration, and repeated episodes of AKI impact outcomes, and that integration of novel urinary biomarkers of tubular injury can also reveal unique subphenotypes of AKI that may not be otherwise readily apparent.

SUMMARY

Studies that further delineate these unique AKI subphenotypes are needed to better understand the impact of AKI in children. Further delineation of these phenotypes has both prognostic and therapeutic implications.

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.

Decreases in Nephrotoxic Pain Medications Are Not Associated With Increased Opioid Utilization in Critically Ill Children

OBJECTIVES

Quality improvement initiatives to decrease rates of nephrotoxic medication exposure have reduced rates of acute kidney injury (AKI) in noncritically ill children. The objective of our study was to analyze the implementation of a similar program in critically ill children and to measure important balancing measures including opioid and benzodiazepine exposure.

DESIGN

Prospective quality improvement study.

SETTING

PICU at Children's Hospital Colorado between 2018 and 2020.

PATIENTS

All children admitted to PICU.

INTERVENTIONS

Quality improvement initiative called Nephrotoxic Injury Negated by Just-In-Time Action (NINJA).

MEASUREMENT AND MAIN RESULTS

Eight thousand eight hundred thirty-three PICU patient admissions were included. Mean rates of nephrotoxic medication exposure/1,000 PICU patient days decreased from 46 to 26, whereas rates of nephrotoxic AKI/1,000 PICU patient days did not change. Nonsteroidal anti-inflammatory drug dispenses per 1,000 patient days were reduced from 521 to 456. Similarly, opioid and benzodiazepine exposures per 1,000 patient days were reduced from 812 to 524 and 441 to 227, respectively, during the study observation period.

CONCLUSIONS

The NINJA intervention was efficaciously implemented in our single-center PICU. Nephrotoxic exposure is a modifiable factor that did not inadvertently increase exposure to opioids and benzodiazepines.

Low birth weight, nephron number and chronic kidney disease

Chronic kidney diseases have a significant impact on morbidity and mortality worldwide. Low birth weight, fetal growth restriction and prematurity are indicators of fetal growth and development disorders associated with a congenital reduction in nephron number, which predisposes to an increased risk for chronic kidney disease. On an individual basis, a small nephron number at birth is not always enough to determine the onset of chronic kidney disease, but it decreases the ability of the kidneys to resist any insults to renal tissue that may occur later in life, such as exposure to nephrotoxic drugs or episodes of acute kidney injury. The high incidence of low birth weight and preterm birth globally suggests that, at the population level, the impact of alterations in fetal development on the subsequent onset of chronic kidney disease could be significant. The implementation of strategies aimed at reducing the incidence of prematurity, fetal growth restriction, as well as other conditions that lead to low birth weight and a reduced nephron number at birth, provides an opportunity to prevent the development of chronic kidney disease in adulthood. For these purposes the coordinated intervention of several specialists, including obstetricians, gynecologists, neonatologists, nephrologists, and family doctors, is necessary. Such strategies can be particularly useful in resource-poor countries, which are simultaneously burdened by maternal, fetal and child malnutrition; poor health; epidemics caused by communicable diseases; and little access to screening and primary care.

Acute kidney injury among preterm infants receiving nonsteroidal anti-inflammatory drugs: A pilot study

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs) are a frequently prescribed class of medications in the neonatal intensive care unit (NICU). We aimed to reveal acute kidney injury (AKI) epidemiology in NSAID-exposed premature infants admitted to the NICU using a standardized definition and determine the percentage of NSAID-exposed patients with adequate serum creatinine (SCr) monitoring.

METHODS

This retrospective study compared infants born at ≤34 weeks gestational age who received NSAID for intraventricular hemorrhage prophylaxis (prophylaxis group) or symptomatic treatment for patent ductus arteriosus (PDA; treatment group) between January and December 2014 at a tertiary NICU. All available SCr and 12-h urine output (UO) values were recorded from admission until day seven post-NSAID exposure. AKI incidence was determined using the neonatal modified Kidney Disease Improving Global Outcomes classification, defined as an increase in SCr (i.e., 1.5 fold rise from previous SCr measurement within seven days or 26.5 mmol/L increase within 48 h) or UO < 1 mL/kg/hour, excluding the first 24 h of life.

RESULTS

We identified 70 eligible subjects; 32 received prophylactic NSAIDs, and 38 received indomethacin or ibuprofen for treating symptomatic PDA. AKI incidence for the entire cohort was 23% (16/70). The prophylaxis group had a significantly lower AKI rate than the treatment group (9% vs. 34%; p = 0.014). The treatment group had a higher proportion of infants with adequate SCr monitoring during NSAID treatment than the prophylaxis group (87% vs. 13%, p < 0.001).

CONCLUSION

NSAID-associated AKI occurred in approximately one-quarter of premature infants overall, and the AKI incidence was higher in infants treated with NSAIDs for the symptomatic treatment of PDA than in those receiving prophylactic treatment during the first day of life. Standardized protocols for monitoring daily SCr and UO after exposure should be implemented for all neonates with NSAID exposure to improve early AKI recognition and management.

Nephrotoxic Exposures and Acute Kidney Injury in Noncritically Ill Children Stratified by Service

OBJECTIVE

The Nephrotoxic Injury Negated by Just-in-Time Action (NINJA) program is a multicenter, quality improvement initiative that identifies patients at risk for nephrotoxic medication-associated acute kidney injury (NTMx-AKI). The purpose of this study was to (1) evaluate the prevalence and types of NTMx exposures and (2) determine the prevalence of NTMx-AKI categorized by service. Exploratory analysis evaluated potential associations between hospital measures and NTMx-AKI.

METHODS

This is a single-center, retrospective chart review of NTMx exposures from January 2019 to June 2020 in noncritically ill children. High NTMx exposures were defined as ≥3 simultaneous nephrotoxins or ≥3 days of either intravenous vancomycin or aminoglycoside. Prevalence of high NTMx and NTMx-AKI rate were normalized to 1000 patient days. A retrospective case-control analysis assessed for potential associations with development of NTMx-AKI.

RESULTS

There were 609 NTMx exposures in 565 patients and 44 (7.2%) episodes of NTMx-AKI. The NTMx prevalence rate per 1000 patient days was highest among liver, neurosurgery, and gastroenterology services. The most commonly used NTMx were vancomycin, intravenous contrast, and nonsteroidal antiinflammatory drugs. The NTMx-AKI rate in exposed patients ranged from 0% to 14% across service lines. AKI was most often attributable to vancomycin. Univariable analyses suggest type and duration of NTMx exposure are associated with development of NTMx-AKI but not with severity.

CONCLUSIONS

NTMx exposures and NTMx-AKI are variable across services. Partnerships with antimicrobial stewardship and multicenter studies are needed to modify NTMx-AKI risk. Ongoing surveillance is needed in patients who do not have normalization of creatinine before discharge.

Acute kidney injury in pediatrics: an overview focusing on pathophysiology

Acute kidney injury (AKI) is defined as an abrupt decline in glomerular filtration rate, with increased serum creatinine and nitrogenous waste products due to several possible etiologies. Incidence in the pediatric population is estimated to be 3.9 per 1,000 hospitalizations, and prevalence among children admitted to intensive care units is 26.9%. Despite being a condition with important incidence and morbimortality, further evidence on pathophysiology and management among the pediatric population is still lacking. This narrative review aimed to summarize and discuss current data on AKI pathophysiology in the pediatric population, considering all the physiological particularities of this age range and common etiologies. Additionally, we reported current diagnostic tools, novel biomarkers, and newly proposed medications that have been studied with the aim of early diagnosis and appropriate treatment of AKI in the future.

Recurrent acute kidney injury in preterm neonates is common and associated with worse outcomes and higher mortality

BACKGROUND

Acute kidney injury (AKI) in preterm neonates is associated with poor outcomes that may worsen in the setting of recurrent episodes of AKI. This study defines and studies the incidence, risk factors, and outcomes of recurrent AKI (rAKI).

METHODS

Retrospective chart review of the neonates born at a gestational age of ≤28 weeks admitted to the neonatal intensive care unit (NICU) between January 2014 and December 2018. We identified AKI based on the serum creatinine (Scr) concentrations using the Kidney Disease: Improving Global Outcomes (KDIGO) criteria. rAKI was defined as the occurrence of AKI after Scr from the prior AKI had returned to baseline.

RESULTS

Forty-nine of the 205 (24%) preterm neonates developed rAKI. An earlier diagnosis (<7 days old) and a higher KDIGO stage (stage 3) at the initial episode of AKI was associated with rAKI (p = 0.03). Preterm neonates with rAKI had higher mortality as compared to those with a single episode of AKI (sAKI) (adjusted odds ratio (aOR) 4.55, 95% confidence interval (CI), 1.12-18.51). Length of stay (LOS) was longer among neonates with rAKI as compared to those with sAKI by 36 days (95% CI 24.9-47.1).

CONCLUSIONS

Recurrent AKI in preterm neonates was associated with earlier episodes and higher KDIGO stage of the initial AKI episode. Neonates with rAKI had higher mortality and longer LOS compared to those with sAKI.

IMPACT

Definition and study of the incidence of rAKI and its associated outcomes among preterm neonates. Recurrent AKI is common among preterm neonates and may contribute to worse outcomes for premature neonates in the NICU. Early recognition of the risk factors for AKI, and effective management of initial AKI and early phase of recurrent AKI may improve outcomes of these preterm neonates.

Impact of nephrotoxic drugs on urinary biomarkers of renal function in very preterm infants

BACKGROUND

Following preterm birth, the immature kidney is exposed to several harmful conditions, with an increased risk of renal impairment. We aimed to assess urinary biomarkers of renal function in very preterm infants during early nephrotoxic treatments.

METHODS

Infants ≤32 weeks' gestation and ≤1500 g were enrolled in this observational prospective study. Urine samples were collected on day 1(T1), 2-4(T2), 5-7(T3), 8-10(T4), 11-13(T5). The following urinary biomarkers were determined: osteopontin (uOPN), epidermal growth factor (uEGF), neutrophil gelatinase-associated lipocalin (uNGAL), cystatin C (uCysC). The infants were grouped according to their exposure to amikacin or ibuprofen during the study period and a between-group comparison of urinary biomarkers at each time point was performed.

RESULTS

Thirty-six infants were included. Urinary CysC, uOPN, and uNGAL rose significantly during ibuprofen or amikacin treatment, while no difference was observed for uEGF. After adjustment for possible influencing factors, amikacin administration was associated with higher uCysC at T1 (p = 0.007) and T2 (p = 0.016), whereas ibuprofen increased uOPN (p = 0.001) and uNGAL concentration (p = 0.009) at T3.

CONCLUSION

Nephrotoxic therapies induce molecule-specific change patterns of renal function biomarkers in treated preterm infants. Serial assessments of these biomarkers may aid to identify neonates at risk of renal impairment and to develop tailored therapeutic approaches.

IMPACT

Despite the wide use of nephrotoxic therapies in neonatal settings, little is known on their effect on renal function biomarkers in preterm infants. This study describes molecule-specific change patterns of urinary biomarkers during ibuprofen and amikacin administration, suggesting underlying pathophysiological effects on renal function. Given their low analytical costs and non-invasive collection, the urinary biomarkers investigated in this study represent a promising strategy for serial monitoring of renal function in at-risk neonates and may aid the early detection of renal function impairment at different kidney levels during nephrotoxic treatments.

Improving acute kidney injury diagnostic precision using biomarkers

Acute kidney injury (AKI) is common in hospitalized patients of all ages and is associated with significant morbidity and mortality. Accurate prediction and early identification of AKI is of utmost importance because no therapy exists to mitigate AKI once it has occurred. Yet, serum creatinine lacks adequate sensitivity and specificity, and quantification of urine output is challenging in incontinent children without indwelling bladder catheters. Integration of clinically available biomarkers have the potential to delineate unique AKI phenotypes that could have important prognostic and therapeutic implications. Plasma Cystatin C, urine neutrophil gelatinase associated lipocalin (NGAL) and the urinary product of tissue inhibitor metalloproteinase (TIMP-2) and insulin growth factor binding protein-7 (IGFBP7) are clinically available. These biomarkers have been studied in heterogenous populations across the age spectrum and in a variety of clinical settings for prediction of AKI. The purpose of this review is to describe and discuss the clinically available AKI biomarkers including how they have been used to delineate AKI phenotypes.