Early prediction of pediatric acute kidney injury from the emergency department: A pilot study

The challenges for developing prognostic prediction models for acute kidney injury in hospitalized children: A systematic review

Importance

Acute kidney injury (AKI) is common in hospitalized children which could rapidly progress into chronic kidney disease if not timely diagnosed. Prognostic prediction models for AKI were established to identify AKI early and improve children's prognosis.

Objective

To appraise prognostic prediction models for pediatric AKI.

Methods

Four English and four Chinese databases were systematically searched from January 1, 2010, to June 6, 2022. Articles describing prognostic prediction models for pediatric AKI were included. The data extraction was based on the CHecklist for critical Appraisal and data extraction for systematic Reviews of prediction Modelling Studies checklist. The risk of bias (ROB) was assessed according to the Prediction model Risk of Bias Assessment Tool guideline. The quantitative synthesis of the models was not performed due to the lack of methods regarding the meta-analysis of prediction models.

Results

Eight studies with 16 models were included. There were significant deficiencies in reporting and all models were considered at high ROB. The area under the receiver operating characteristic curve to predict AKI ranged from 0.69 to 0.95. However, only about one-third of models have completed internal or external validation. The calibration was provided only in four models. Three models allowed easy bedside calculation or electronic automation, and two models were evaluated for their impacts on clinical practice.

Interpretation

Besides the modeling algorithm, the challenges for developing prediction models for pediatric AKI reflected by the reporting deficiencies included ways of handling baseline serum creatinine and age-dependent blood biochemical indexes. Moreover, few prediction models for pediatric AKI were performed for external validation, let alone the transformation in clinical practice. Further investigation should focus on the combination of prediction models and electronic automatic alerts.

Heart rate to identify non-febrile children with dehydration and acute kidney injury in emergency department: a prospective validation study

We previously developed and retrospectively validated the estimated percentage of heart rate variation (EHRV) as a predictor of the composite outcome of ≥ 5% dehydration and/or acute kidney injury (AKI) in non-febrile children. The current study aimed to prospectively validate EHRV as a predictor for dehydration or AKI in a different cohort of children attending the Pediatric Emergency Department. From July 2022 to August 2023, 256 pediatric patients aged 0-18 years attending the Pediatric Emergency Department were enrolled. EHRV was calculated as follows: [(HR at admission - 50th percentile of HR for age and sex)/HR at admission] × 100. Dehydration was categorized as < 5% or ≥ 5% fluid deficit. AKI was defined according to KDIGO creatinine criteria. Statistical analyses included receiver-operating characteristic (ROC) curves and logistic regression analysis. Among enrolled patients, 52 had ≥ 5% dehydration, 50 had AKI, and 16 had both conditions. EHRV demonstrated significant predictive ability for both ≥ 5% dehydration (AUROC = 0.71; 95% confidence interval (CI), 0.63-0.78; p < 0.001) and AKI (AUROC = 0.78; 95% CI, 0.71-0.84; p < 0.001). An EHRV > 24.5% was associated with an increased odds ratio (OR), adjusted for confounders, of ≥ 5% dehydration (OR = 3.5; 95% CI, 1.6-8.0; p = 0.003) and AKI (OR = 3.4; 95% CI, 1.6-7.3; p = 0.002). The sensitivity and specificity of this cut-off were 34% and 83% for ≥ 5% dehydration and 36% and 84% for AKI, respectively.

CONCLUSIONS

This study prospectively validates the clinical utility of EHRV in predicting dehydration and AKI in a pediatric emergency care setting. An EHRV > 24.5% could serve as a marker for suspecting dehydration or AKI. Further validation across diverse patient populations and settings is needed.

WHAT IS KNOWN

• An increased heart rate (HR) is a readily detectable sign of dehydration in children. • In a retrospective validation cohort, an estimated HR variation (EHRV) greater than 24.5% compared to the 50th percentile of HR was predictive of ≥ 5% dehydration and/or acute kidney injury (AKI) in non-febrile patients.

WHAT IS NEW

• We prospectively validated the clinical utility of EHRV in predicting dehydration and AKI in a pediatric emergency care setting. • We confirmed that an EHRV greater than 24.5% is associated with increased odds of ≥ 5% dehydration and AKI.

Sociodemographic Disparities in 1-Year Outcomes of Children With Community-Acquired Acute Kidney Injury

Importance

Racial disparities have been identified in pediatric community-acquired acute kidney injury (CA-AKI), and they are associated with increased risk of child mortality, morbidity, and progression of kidney disease.

Objective

To assess clinical outcomes at 1 year among children with CA-AKI, stratified by age, race, and ethnicity.

Design, Setting, and Participants

This retrospective cohort study is a population-based analysis of deidentified, aggregated electronic health record data collected by 61 large health care organizations from 2003 to 2023 and accessed through the TriNetX platform. Outcomes were assessed at 1 year after a CA-AKI episode. Participants included pediatric patients (aged <18 years) with AKI. Data were accessed in January 2024.

Exposure

A diagnosis of CA-AKI and sociodemographic factors such as race, ethnicity, and age, as reported in electronic health records.

Main Outcomes and Measures

The primary end point of this study was to assess differences in clinical outcomes within 1 year of an episode of CA-AKI, including all-cause emergency department (ED) visits, intensive care unit (ICU) admissions, mechanical intubation and ventilation, and mortality. Risk was compared between White children and Asian (including Asian, Native Hawaiian, and Other Pacific Islander), Black, and Hispanic children, stratified by age group. Measures of association, Cox proportional hazard analyses, and Kaplan-Meier survival curves were performed within the TriNetX Advanced Analytics Platform between racial and ethnic groups for each analysis.

Results

From the total sample of 18 152 children, those with hospital-acquired AKI, chronic kidney disease, end-stage kidney failure, or dialysis dependence were excluded, leaving a final cohort of 17 125 children (mean [SD] age, 11.2 [5.2] years; 9424 male [55.3%]). Eligible patients were divided into racial and ethnic groups as follows: non-Hispanic Asian, 1169 children (6.5%); non-Hispanic Black, 4636 children (27.3%); Hispanic, 1786 children (10.2%); and non-Hispanic White, 9534 children (55.9%). Patients were further subdivided into groups aged 0 to 9 years (546 Asian children, 1675 Black children, 689 Hispanic children, and 3340 White children) and 10 to 18 years (623 Asian children, 2961 Black children, 1091 Hispanic children, and 6104 White children). Within 1 year of CA-AKI diagnosis, compared with White children, Black children experienced greater rates of ED visits (hazard ratio [HR], 1.53; 95% CI, 1.40-1.67), ICU admissions (HR, 1.31; 95% CI, 1.16-1.47), mechanical ventilation (HR, 1.33; 95% CI, 1.13-1.56), and all-cause mortality (HR, 1.27; 95% CI, 1.09-1.48), as well as the greatest risk for composite outcomes (HR, 1.43; 95% CI, 1.33-1.53). Hispanic children experienced greater rates of ED visits (HR, 1.40; 95% CI, 1.21-1.62) and the greatest risk of all-cause mortality (HR, 1.66; 95% CI, 1.31-2.09), whereas Asian children experienced greater rates of mechanical ventilation (HR, 1.69; 95% CI, 1.26-2.27), compared with White children. Black and Hispanic children aged 0 to 9 years were at greatest risk of experiencing poor clinical outcomes. Black children had a 11.41% lower survival probability and Hispanic children had a 7.14% lower survival probability compared with White children after an initial ED encounter.

Conclusions and Relevance

Among children with an identified episode of CA-AKI diagnosed in an ED, within 1 year, Black and Hispanic children had a poorer survival probability compared with White children. Future studies are needed to understand these disparities and improve awareness and follow-up after emergency care.

A proposed framework for advancing acute kidney injury risk stratification and diagnosis in children: a report from the 26th Acute Disease Quality Initiative (ADQI) conference

Acute kidney injury (AKI) in children is associated with increased morbidity, reduced health-related quality of life, greater resource utilization, and higher mortality. Improvements in the timeliness and precision of AKI diagnosis in children are needed. In this report, we highlight existing, novel, and on-the-horizon diagnostic and risk-stratification tools for pediatric AKI, and outline opportunities for integration into clinical practice. We also summarize pediatric-specific high-risk diagnoses and exposures for AKI, as well as the potential role of real-time risk stratification and clinical decision support to improve outcomes. Lastly, the key characteristics of important pediatric AKI phenotypes will be outlined. Throughout, we identify key knowledge gaps, which represent prioritized areas of focus for future research that will facilitate a comprehensive, timely and personalized approach to pediatric AKI diagnosis and management.

Success of the acute renal angina index in the early prediction of acute kidney injury in the emergency department

INTRODUCTION

It is mentioned that the acute renal angina index (aRAI), a new concept, can be used in emergency departments to calculate and accurately predict the risk of developing acute kidney injury (AKI). The aims of the study included: to evaluate the predictive performance of the aRAI (AKI risk classification tool) in predicting AKI in the pediatric emergency department.

METHOD

Patients who met the criteria for systemic inflammatory response syndrome were examined. AKI was defined with creatinine N1.5× baseline 24-72 hours after hospitalization. aRAI and original RAI scores were calculated for patients and were shown as renal angina positive (RA+) above a population-derived threshold. The performance of aRAI in predicting AKI compared to changes in creatinine and original RAI was evaluated.

RESULTS

In total, 241 eligible subjects were enrolled. The median age of the patients was 17 months (min-max 1-192). AKI developed in 60 (24.8%) of the patients. According to the aRAI, 76 (31.5%) of 241 patients were RA(+). The aRAI had an NPV of 1.00 and an AUC of 0.948 (0.914-0.983) for the prediction of AKI. Sensitivity was 95% for the aRAI as compared to 48% for an elevation in SCr noted to be at least two times greater than the baseline while in the PED and 61% for original RAI.

CONCLUSIONS

The aRAI is easily computable, does not depend on complex computational or derivation methods, and is universally accessible. We confirm and extend the findings of previous study reporting the performance of RAI for early prediction of AKI.

Update on Pediatric Acute Kidney Injury

Acute kidney injury (AKI) is common in children and is associated with significant morbidity and mortality. In the last decade our understanding of AKI has improved significantly, and it is now considered a systemic disorder that affects other organs including heart, lung, and brain. In spite of its limitations, serum creatinine remains the mainstay in the diagnosis of AKI. However, newer approaches such as urinary biomarkers, furosemide stress test, and clinical decision support are being increasingly used and have the potential to improve the accuracy and timeliness of AKI diagnosis.

Diagnostic accuracy of renal angina index alone or in combination with biomarkers for predicting acute kidney injury in children

Early recognition of patients at risk for severe acute kidney injury (AKI) by renal angina index (RAI) may help in the early institution of preventive measures. Objective was to evaluate performance of RAI alone or in combination with biomarkers in predicting severe AKI (KDIGO stage 2 and 3 or equivalent) and receipt of kidney replacement therapy (KRT) in critically ill children. We searched PubMed, EMBASE, Web of Sciences, and CENTRAL for studies published till May 2021. Search terms included acute kidney injury, pediatrics, adolescent, renal angina index, and biomarker. Proceedings of relevant conferences and references of included studies were also scrutinized. Two reviewers independently assessed the study eligibility. Cohort and cross-sectional studies evaluating the diagnostic performance of RAI in predicting AKI or receipt of KRT in children were included. Eligible participants were the children less than 18 years with RAI assessment on day 0 ofadmission. We followed PRISMA-DTA guidelines and used the QUADAS-2 tool for quality assessment. A bivariate model for meta-analysis was used to calculate the summary estimates of diagnostic parameters. Major outcomes were the diagnostic accuracy of RAI (≥ 8) alone or with biomarkers in predicting severe AKI and KRT receipt. Diagnostic accuracy was reported using summary sensitivity, specificity, and area under the curve (AUC). Overall, 22 studies (24 reports, 14,001 participants) were included. RAI ≥ 8 on day 0 has summary sensitivity, specificity, and AUC of 0.86 (95% CI, 0.77-0.92), 0.77 (0.68-0.83), and 0.88 (0.85-0.91) respectively for prediction of severe AKI on day 3. In comparison, a combination of RAI and urinary neutrophil gelatinase-associated lipocalin (NGAL) showed summary sensitivity, specificity, and AUC of 0.76 (0.62-0.85), 0.89 (0.74-0.96), and 0.87 (0.84-0.90) respectively for predicting severe AKI. The sensitivity, specificity, and AUC of RAI for predicting receipt of KRT were 0.82 (0.71-0.90), 0.74 (0.66-0.81), and 0.85 (0.81-0.88) respectively. In meta-regression, only the study setting (sepsis vs. heterogenous) was associated with heterogeneity. We observed substantial heterogeneity among eligible studies. Five studies had concerns in patient selection, and seven studies also had applicability concerns in patient selection for this review. Moderate certainty evidence showed that RAI ≥ 8 has good predicting ability in recognizing children at risk of severe AKI and receipt of KRT. The combination of urinary NGAL and RAI further improves the predicting ability (low-certainty evidence). Further studies are required on the context-driven assessment of novel biomarkers in the early prediction of AKI in RAI-positive children. Systematic review registration number: CRD4202122268. A higher resolution version of the Graphical abstract is available as Supplementary information.

Re-evaluating Renal Angina Index: An Authentic, Evidence-Based Instrument for Acute Kidney Injury Assessment: Critical Appraisal

Background/Introduction: Renal angina index (RAI) used to calculate and accurately predict risk for the development of acute kidney injury (AKI) has been heavily explored. AKI is traditionally diagnosed by an increase in serum creatinine (SCr) concentration or oliguria, both of which are neither specific nor sensitive, especially among children. An RAI score may be calculated by combining objective signs of kidney dysfunction (such as SCr) and patient context, such as AKI risk factors, thus potentially serving as a more accurate indicator for AKI. Objective: Due to the propitious and novel nature of RAI, this editorial commentary aims to analyze the current literature on RAI and determine how well RAI serves as a predictor of AKI outcomes. Method: A comprehensive literature search was conducted in PubMed/Medline and Google Scholar between January 2012 and July 2020. Literature included the prognostic aspect of early prediction of AKI in the pediatric and adult population via RAI. Results: The initial literature search included 149 studies, and a total of 10 studies reporting the outcomes of interest were included. The overall sample size across these studies was 11,026. The predictive ability of RAI had a pooled (95% CI) sensitivity of 79.21%, specificity of 73.22%, and negative predictive value of 94.83%. Conclusion: RAI shows benefit in the prediction of AKI among adult and pediatric populations. However, there is a lack of sufficient data, and further prospective studies are needed in pediatric populations to use RAI as a principal AKI indicator among clinicians.

Assessment of early renal angina index for prediction of subsequent severe acute kidney injury during septic shock in children

Background

Acute kidney injury (AKI) is independently related to the adverse outcome of septic shock, but it lacks effective early predictors. Renal anginal index (RAI) was used to predict subsequent severe AKI (AKIs) in critically ill patients. The application of RAI in children with septic shock has not been reported. This study aims to evaluate the efficacy of early RAI in predicting subsequent AKIs within 3 days after PICU admission in children with septic shock by comparing with early fluid overload (FO) and early creatinine elevation.

Methods

Sixty-six children admitted to PICU aged 1 month to 16 years old, with septic shock from January 2016 to December 2019 were analyzed retrospectively. According to the 2012 Kidney Disease Improving Global outcomes (KDIGO) criteria, AKIs was defined by the KDIGO stage ≥2 within 3 days after PICU admission. Early RAI positive (RAI+) was defined as RAI ≥ 8 within 12 h of PICU admission. Any elevation of serum creatinine (SCr) over baseline within 12 h after PICU admission was denoted as “Early SCr > base”. Early FO positive (FO+) was defined as FO > 10% within 24 h of PICU admission.

Results

Of 66 eligible cases, the ratio of early RAI+, early SCr > base, early FO+ was 57.57, 59.09 and 16.67% respectively. The incidence of AKIs in early RAI+ group (78.94%) was higher than that in early RAI- group (21.42%) (p = 0.04), and there was no significant difference compared with the early FO+ group (71.79%) and early SCr > base group (81.82%) (P > 0.05). After adjustment for confounders, early RAI+ was independently associated with the occurrence of AKIs within 3 days (OR 10.04, 95%CI 2.39–42.21, p < 0.01). The value of early RAI+ (AUC = 0.78) to identify patients at high risk of AKIs was superior to that of early SCr > base (AUC = 0.70) and early FO+ (AUC = 0.58). A combination of serum lactate with early RAI+ improved the predictive performance for assessing AKIs (AUC = 0.83).

Conclusions

Early RAI could be used as a more convenient and effective index to predict the risk of AKIs in children with septic shock within 3 days. Early RAI+ combined with serum lactate improved the predictive performance for assessing AKIs.