Acute Kidney Injury Incidence in Noncritically Ill Hospitalized Children, Adolescents, and Young Adults: A Retrospective Observational Study

Fifteen-year temporal changes in rates of acute kidney injury among children in Denmark

BACKGROUND

We aimed to examine temporal changes in the annual rate of acute kidney injury (AKI) in Danish children and associated changes in patient characteristics including potential underlying risk factors.

METHODS

In this population-based cohort study, we used plasma creatinine measurements from Danish laboratory databases to identify AKI episodes in children aged 0-17 years from 2007 to 2021. For each child, the first AKI episode per calendar year was included. We estimated the annual crude and sex- and age-standardized AKI rate as the number of children with an AKI episode divided by the total number of children as reported by census numbers. Using Danish medical databases, we assessed patient characteristics including potential risk factors for AKI, such as use of nephrotoxic medication, surgery, sepsis, and perinatal factors.

RESULTS

In total, 14,200 children contributed with 16,345 AKI episodes over 15 years. The mean annual AKI rate was 148 (95% CI: 141-155) per 100,000 children. From 2007 to 2021, the annual AKI rate demonstrated minor year-to-year variability without any discernible overall trend. The highest AKI rate was recorded in 2007 at 174 (95% CI: 161-187) per 100,000 children, while the lowest rate occurred in 2012 at 129 (95% CI: 118-140) per 100,000 children. In 2021, the AKI rate was 148 (95% CI: 141-155) per 100,000 children. Characteristics of children with AKI were similar throughout the study period.

CONCLUSION

The rate of AKI among Danish children was stable from 2007 to 2021 with little variation in patient characteristics over time.

Pediatric AKI in the real world: changing outcomes through education and advocacy-a report from the 26th Acute Disease Quality Initiative (ADQI) consensus conference

BACKGROUND

Acute kidney injury (AKI) is independently associated with increased morbidity and mortality across the life course, yet care for AKI remains mostly supportive. Raising awareness of this life-threatening clinical syndrome through education and advocacy efforts is the key to improving patient outcomes. Here, we describe the unique roles education and advocacy play in the care of children with AKI, discuss the importance of customizing educational outreach efforts to individual groups and contexts, and highlight the opportunities created through innovations and partnerships to optimize lifelong health outcomes.

METHODS

During the 26th Acute Disease Quality Initiative (ADQI) consensus conference, a multidisciplinary group of experts discussed the evidence and used a modified Delphi process to achieve consensus on recommendations on AKI research, education, practice, and advocacy in children.

RESULTS

The consensus statements developed in response to three critical questions about the role of education and advocacy in pediatric AKI care are presented here along with a summary of available evidence and recommendations for both clinical care and research.

CONCLUSIONS

These consensus statements emphasize that high-quality care for patients with AKI begins in the community with education and awareness campaigns to identify those at risk for AKI. Education is the key across all healthcare and non-healthcare settings to enhance early diagnosis and develop mitigation strategies, thereby improving outcomes for children with AKI. Strong advocacy efforts are essential for implementing these programs and building critical collaborations across all stakeholders and settings.

Epidemiology of acute kidney injury in children: a report from the 26th Acute Disease Quality Initiative (ADQI) consensus conference

The nephrology and critical care communities have seen an increase in studies exploring acute kidney injury (AKI) epidemiology in children. As a result, we now know that AKI is highly prevalent in critically ill neonates, children, and young adults. Furthermore, children who develop AKI experience greater morbidity and higher mortality. Yet knowledge gaps still exist that suggest a more comprehensive understanding of AKI will form the foundation for future efforts designed to improve outcomes. In particular, the areas of community acquired AKI, AKI in non-critically ill children, and cohorts from low-middle income countries have not been well studied. Longer-term functional outcomes and patient-centric metrics including social determinants of health, quality of life, and healthcare utilization should be the foci of the next phase of scholarship. Current definitions identify AKI-based upon evidence of dysfunction which serves as a proxy for injury; biomarkers capable of identifying injury as it occurs are likely to more accurately define populations with AKI. Despite the strength of the association, the causal and mechanistic relationships between AKI and poorer outcomes remain inadequately examined. A more robust understanding of the relationship represents a potential to identify therapeutic targets. Once established, a more comprehensive understanding of AKI epidemiology in children will allow investigation of preventive, therapeutic, and quality improvement interventions more effectively.

Drugs in treating paediatric acute kidney injury

Acute kidney injury (AKI) is a complex syndrome which affects a significant proportion of hospitalized children. The breadth and impact of AKI on health outcomes in both adults and children have come to the fore in recent years with increasing awareness encouraging research advancement. Despite this, management strategies for most types of AKI remain heavily reliant on fluid and electrolyte management, hemodynamic optimization, nephrotoxin avoidance and appropriate initiation of kidney replacement therapy. Specific drugs targeting the mechanisms involved in AKI remain elusive. Recent improvement in appreciation of the complexity of AKI pathophysiology has allowed for greater opportunity to consider novel therapeutic agents. A number of drugs specifically targeting AKI are in various stages of development. This review will consider some novel and repurposed agents; interrogate the plausibility of the proposed mechanisms of action, as they relate to what we know about the pathophysiology of AKI; and review the level of existing literature supporting their efficacy. The evidence base, particularly in children, is limited.

Blood analysis for screening of electrolyte and kidney function alterations in patients with febrile urinary tract infection

AIM

To describe the prevalence, severity, risk factors, and clinical relevance of electrolyte disturbances and acute kidney injury (AKI) during febrile urinary tract infection (fUTI).

METHODS

Retrospective observational study of well/fair-appearing patients between 2 months and 16 years, with no previous relevant medical history, diagnosed with fUTI in the paediatric emergency department (PED) with subsequent microbiological confirmation. Analytical alteration (AA) data were considered: AKI (creatinine elevation × 1.5 the median for age), plasma sodium alteration (≤130 or ≥150 mEq/L), and potassium alteration (≤3 or ≥6 mEq/L).

RESULTS

We included 590 patients, 17.8% presented AA (13 hyponatremia, 7 hyperkalaemia, and 87 AKI). No patient presented severe analytic alterations or a higher frequency of symptoms potentially attributable to these alterations (seizures, irritability, or lethargy). Risk factors associated with these AA were clinical dehydration (OR = 3.5 95% CI: 1.04-11.7; p = 0.044) and presenting a temperature >39°C (OR = 1.9 95% CI: 1.14-3.1; p = 0.013).

CONCLUSIONS

Electrolyte and renal function disturbances are infrequent in the previously healthy paediatric population with a fUTI. If present, they are asymptomatic and not severe. Based on our results, performing systematic blood analysis to rule out AA appears no longer justified, especially in the absence of risk factors.

Patient level factors increase risk of acute kidney disease in hospitalized children with acute kidney injury

BACKGROUND

Studies in adults have shown that persistent kidney dysfunction ≥7-90 days following acute kidney injury (AKI), termed acute kidney disease (AKD), increases chronic kidney disease (CKD) and mortality risk. Little is known about the factors associated with the transition of AKI to AKD and the impact of AKD on outcomes in children. The aim of this study is to evaluate risk factors for progression of AKI to AKD in hospitalized children and to determine if AKD is a risk factor for CKD.

METHODS

Retrospective cohort study of children age ≤18 years admitted with AKI to all pediatric units at a single tertiary-care children's hospital between 2015 and 2019. Exclusion criteria included insufficient serum creatinine values to evaluate for AKD, chronic dialysis, or previous kidney transplant.

RESULTS

A total of 528 children with AKI were included in the study. There were 297 (56.3%) hospitalized AKI survivors who developed AKD. Among children with AKD, 45.5% developed CKD compared to 18.7% in the group without AKD (OR 4.0, 95% CI 2.1-7.4, p-value <0.001 using multivariable logistic regression analysis including other covariates). Multivariable logistic regression model identified age at AKI diagnosis, PCICU and NICU admission, prematurity, malignancy, bone marrow transplant, previous AKI, mechanical ventilation, AKI stage, duration of kidney injury, and need for kidney replacement therapy during day 1-7 as risk factors for AKD after AKI.

CONCLUSIONS

AKD is common among hospitalized children with AKI and multiple risk factors are associated with AKD. Children that progress from AKI to AKD are at higher risk of developing CKD. A higher resolution version of the Graphical abstract is available as Supplementary information.

Epidemiology of childhood acute kidney injury in England using e-alerts

Background

Few studies describe the epidemiology of childhood acute kidney injury (AKI) nationally. Laboratories in England are required to issue electronic (e-)alerts for AKI based on serum creatinine changes. This study describes a national cohort of children who received an AKI alert and their clinical course.

Methods

A cross-section of AKI episodes from 2017 are described. Hospital record linkage enabled description of AKI-associated hospitalizations including length of stay (LOS) and critical care requirement. Risk associations with critical care (hospitalized cohort) and 30-day mortality (total cohort) were examined using multivariable logistic regression.

Results

In 2017, 7788 children (52% male, median age 4.4 years, interquartile range 0.9-11.5 years) experienced 8927 AKI episodes; 8% occurred during birth admissions. Of 5582 children with hospitalized AKI, 25% required critical care. In children experiencing an AKI episode unrelated to their birth admission, Asian ethnicity, young (<1 year) or old (16-<18 years) age (reference 1-<5 years), and high peak AKI stage had higher odds of critical care. LOS was higher with peak AKI stage, irrespective of critical care admission. Overall, 30-day mortality rate was 3% (n = 251); youngest and oldest age groups, hospital-acquired AKI, higher peak stage and critical care requirement had higher odds of death. For children experiencing AKI alerts during their birth admission, no association was seen between higher peak AKI stage and critical care admission.

Conclusions

Risk associations for adverse AKI outcomes differed among children according to AKI type and whether hospitalization was related to birth. Understanding the factors driving AKI development and progression may help inform interventions to minimize morbidity.

Acute Kidney Injury: Gaps and Opportunities for Knowledge and Growth

Acute kidney injury (AKI) occurs frequently in hospitalized patients, regardless of age or prior medical history. Increasing awareness of the epidemiologic problem of AKI has directly led to increased study of global recognition, diagnostic tools, both reactive and proactive management, and analysis of long-term sequelae. Many gaps remain, however, and in this article we highlight opportunities to add significantly to the increasing bodies of evidence surrounding AKI. Practical considerations related to initiation, prescription, anticoagulation, and monitoring are discussed. In addition, the importance of AKI follow-up evaluation, particularly for those surviving the receipt of renal replacement therapy, is highlighted as a push for global equity in the realm of critical care nephrology is broached. Addressing these gaps presents an opportunity to impact patient care directly and improve patient outcomes.

Long-term outcomes of acute kidney injury in children

PURPOSE OF REVIEW

Acute kidney injury (AKI) affects up to 35% of all critically ill children and is associated with substantial short-term morbidity and mortality. However, the link between paediatric AKI and long-term adverse outcomes remains incompletely understood. This review highlights the most recent clinical data supporting the role of paediatric AKI as a risk factor for long-term kidney and cardiovascular consequences. In addition, it stresses the need for long-term surveillance of paediatric AKI survivors.

RECENT FINDINGS

Recent large-scale studies have led to an increasing understanding that paediatric AKI is a significant risk factor for adverse outcomes such as hypertension, cardiovascular disease and chronic kidney disease (CKD) over time. These long-term sequelae of paediatric AKI are most often observed in vulnerable populations, such as critically ill children, paediatric cardiac surgery patients, children who suffer from severe infections and paediatric cancer patients.

SUMMARY

A growing body of research has shown that paediatric AKI is associated with long-term adverse outcomes such as CKD, hypertension and cardiovascular disease. Although therapeutic pathways tailored to individual paediatric AKI patients are yet to be validated, we provide a framework to guide monitoring and prevention in children at the highest risk for developing long-term kidney dysfunction.

Comparative Analysis of Intensive Care Prognosis Scoring Systems and Acute Kidney Injury Scores (AKIN and pRIFLE) in Critically Ill Children

The development of AKI (acute kidney injury) in critically ill patients in pediatric intensive care units (PICUs) is one of the most important factors affecting mortality. There are scoring modalities used to predict mortality in PICUs. We compared the AKIN (Acute Kidney Injury Network) and pRIFLE (pediatric risk, injury, failure, loss, and end stage) AKI classifications and PICU scoring modalities in this study. Methods: A total of 716 children, whose serum creatinine levels were within the normal limits at the time of admission to the PICU between January 2018 and December 2020, were included. Along with the demographic and clinical variables, AKIN and pRIFLE classifications were recorded at the most advanced stage of AKI. Along with the PIM-2, PRISM III, and PELOD-2 scores, the highest value of the pSOFA score was recorded. Results: According to the pRIFLE and AKIN classifications, 62 (8.7%) patients developed kidney injury, which had a statistically significant effect on mortality. The occurrence of renal injury was found to be statistically strongly and significantly correlated with high PRISM III, PELOD-2, and pSOFA scores. When the stages of kidney injury according to the AKIN criteria were compared with the PRISM III, PELOD 2, and pSOFA scores, a significant difference was found between the patients who did not develop AKI and those who developed stage 1, stage 2, and stage 3 kidney injury. For the PRISM III, PELOD 2, and pSOFA scores, there were no significant differences between the stages according to the AKIN criteria. A substantial difference was discovered between the patients who did not develop AKI and those who were in the risk, injury, and failure plus loss stages according to the pRIFLE criteria. According to the PIM-2 ratio and pRIFLE criteria, there was a statistically significant difference between patients in the injury and failure plus loss stages and those who did not develop AKI. Conclusions: Our study is the first pediatric study to show a substantial correlation between the variables associated with the PICU scoring modalities in critically ill children with AKI. Identifying the risk factors for the development of AKI and planning antimicrobial regimens for patients with favorable prognoses at the time of PICU admission could lower mortality rates.

Comparison of diagnostic criteria for acute kidney injury in critically ill children: a multicenter cohort study

Background

Substantial interstudy heterogeneity exists in defining acute kidney injury (AKI) and baseline serum creatinine (SCr). This study assessed AKI incidence and its association with pediatric intensive care unit (PICU) mortality under different AKI and baseline SCr definitions to determine the preferable approach for diagnosing pediatric AKI.

Methods

In this multicenter prospective observational cohort study, AKI was defined and staged according to the Kidney Disease: Improving Global Outcome (KDIGO), modified KDIGO, and pediatric reference change value optimized for AKI (pROCK) definitions. The baseline SCr was calculated based on the Schwartz formula or estimated as the upper normative value (NormsMax), admission SCr (AdmSCr) and modified AdmSCr. The impacts of different AKI definitions and baseline SCr estimation methods on AKI incidence, severity distribution and AKI outcome were evaluated.

Results

Different AKI definitions and baseline SCr estimates led to differences in AKI incidence, from 6.8 to 25.7%; patients with AKI across all definitions had higher PICU mortality ranged from 19.0 to 35.4%. A higher AKI incidence (25.7%) but lower mortality (19.0%) was observed based on the Schwartz according to the KDIGO definition, which however was overcome by modified KDIGO (AKI incidence: 16.3%, PICU mortality: 26.1%). Furthermore, for the modified KDIGO, the consistencies of AKI stages between different baseline SCr estimation methods were all strong with the concordance rates > 90.0% and weighted kappa values > 0.8, and PICU mortality increased pursuant to staging based on the Schwartz. When the NormsMax was used, the KDIGO and modified KDIGO led to an identical AKI incidence (13.6%), but PICU mortality did not differ among AKI stages. For the pROCK, PICU mortality did not increase pursuant to staging and AKI stage 3 was not associated with mortality after adjustment for confounders.

Conclusions

The AKI incidence and staging vary depending on the definition and baseline SCr estimation method used. The modified KDIGO definition based on the Schwartz method leads AKI to be highly relevant to PICU mortality, suggesting that it may be the preferable approach for diagnosing AKI in critically ill children and provides promise for improving clinicians’ ability to diagnose pediatric AKI.

Vancomycin-associated acute kidney injury epidemiology in children: a systematic review

INTRODUCTION

Vancomycin is a recognised cause of drug-induced acute kidney injury (AKI).

OBJECTIVE

The aim of this systematic review was to summarise the incidence of, and the risk factors for, vancomycin-associated AKI (v-AKI) in children.

DESIGN

A systematic search was performed in November 2020 on the search engines PubMed, Web of Science and Medline, using predefined search terms. The inclusion criteria were primary paediatric studies, intervention with vancomycin and studies that included AKI as an outcome. Study quality was assessed using the relevant Critical Appraisal Skills Programme checklist. The data are reported using descriptive statistics.

RESULTS

890 studies were identified and screened with 25 studies suitable for inclusion. A cohort of 12 730 patients with v-AKI were included and the incidence of v-AKI in children was found to be 11.8% (1.6%-27.2%). The median age of the cohort was 2.5 years (range 0-23) and 57% were male patients. Risk factors that increased the likelihood of v-AKI were concomitant use of nephrotoxic medications, increased trough concentrations and, to a lesser extent, increased dose, longer duration of treatment, impaired renal function and if the patient required paediatric intensive care.

CONCLUSIONS

The incidence of v-AKI in children is significant and methods to reduce this risk should be considered. Further prospective interventional studies to understand the mechanisms of nephrotoxicity from vancomycin are needed and targeting risk factors may make vancomycin administration safer.

Acute kidney injury in critically ill children: predictive value of renal arterial Doppler assessment

BACKGROUND

Renal resistive index (RRI) and renal pulsatility index (RPI) are Doppler-based variables proposed to assess renal perfusion at the bedside in critically ill patients. This study aimed to assess the accuracy of such variables to predict acute kidney injury (AKI) in mechanically ventilated children.

METHODS

Consecutive children aged <14 years underwent kidney Doppler ultrasound examination within 24 h of invasive mechanical ventilation. Renal resistive index (RRI) and renal pulsatility index (RPI) were measured. The primary outcome was severe AKI (KDIGO stage 2 or 3) on day 3.

RESULTS

On day 3, 22 patients were classified as having AKI, of which 12 were severe. RRI could effectively predict severe AKI (area under the ROC curve [AUC] = 0.94) as well as RPI (AUC = 0.86). The optimal cut-off for RRI was 0.85 (sensitivity, 91.7%; specificity, 84.7%; PPV, 50.0%; and NPV, 98.4%). Similar results were obtained when the accuracy to predict AKI on day 5 was assessed. Significant correlations were observed between RRI and estimated glomerular filtration rate at enrollment (ρ = -0.495) and on day 3 (ρ = -0.467).

CONCLUSIONS

Renal Doppler ultrasound may be a promising tool to predict AKI in critically ill children under invasive mechanical ventilation.

IMPACT

Early recognition of acute kidney injury (AKI) is essential to promptly initiate supportive care aimed at restoring renal perfusion, which may prevent or attenuate acute tubular necrosis. Renal arterial Doppler-based parameters are rapid, noninvasive, and repeatable variables that may be promising for the prediction of AKI in children. To the best of our knowledge, this is the first study to evaluate the use of renal Doppler-based variables to predict AKI in critically ill children. The present study found that Doppler-based variables could accurately predict the occurrence of severe AKI and were correlated with urinary output and diuretic use.

Consensus-Based Recommendations on Priority Activities to Address Acute Kidney Injury in Children: A Modified Delphi Consensus Statement

IMPORTANCE

Increasing evidence indicates that acute kidney injury (AKI) occurs frequently in children and young adults and is associated with poor short-term and long-term outcomes. Guidance is required to focus efforts related to expansion of pediatric AKI knowledge.

OBJECTIVE

To develop expert-driven pediatric specific recommendations on needed AKI research, education, practice, and advocacy.

EVIDENCE REVIEW

At the 26th Acute Disease Quality Initiative meeting conducted in November 2021 by 47 multiprofessional international experts in general pediatrics, nephrology, and critical care, the panel focused on 6 areas: (1) epidemiology; (2) diagnostics; (3) fluid overload; (4) kidney support therapies; (5) biology, pharmacology, and nutrition; and (6) education and advocacy. An objective scientific review and distillation of literature through September 2021 was performed of (1) epidemiology, (2) risk assessment and diagnosis, (3) fluid assessment, (4) kidney support and extracorporeal therapies, (5) pathobiology, nutrition, and pharmacology, and (6) education and advocacy. Using an established modified Delphi process based on existing data, workgroups derived consensus statements with recommendations.

FINDINGS

The meeting developed 12 consensus statements and 29 research recommendations. Principal suggestions were to address gaps of knowledge by including data from varying socioeconomic groups, broadening definition of AKI phenotypes, adjudicating fluid balance by disease severity, integrating biopathology of child growth and development, and partnering with families and communities in AKI advocacy.

CONCLUSIONS AND RELEVANCE

Existing evidence across observational study supports further efforts to increase knowledge related to AKI in childhood. Significant gaps of knowledge may be addressed by focused efforts.

Outcome prediction for acute kidney injury among hospitalized children via eXtreme Gradient Boosting algorithm

Acute kidney injury (AKI) is common among hospitalized children and is associated with a poor prognosis. The study sought to develop machine learning-based models for predicting adverse outcomes among hospitalized AKI children. We performed a retrospective study of hospitalized AKI patients aged 1 month to 18 years in the Second Xiangya Hospital of Central South University in China from 2015 to 2020. The primary outcomes included major adverse kidney events within 30 days (MAKE30) (death, new renal replacement therapy, and persistent renal dysfunction) and 90-day adverse outcomes (chronic dialysis and death). The state-of-the-art machine learning algorithm, eXtreme Gradient Boosting (XGBoost), and the traditional logistic regression were used to establish prediction models for MAKE30 and 90-day adverse outcomes. The models’ performance was evaluated by split-set test. A total of 1394 pediatric AKI patients were included in the study. The incidence of MAKE30 and 90-day adverse outcomes was 24.1% and 8.1%, respectively. In the test set, the area under the receiver operating characteristic curve (AUC) of the XGBoost model was 0.810 (95% CI 0.763–0.857) for MAKE30 and 0.851 (95% CI 0.785–0.916) for 90-day adverse outcomes, The AUC of the logistic regression model was 0.786 (95% CI 0.731–0.841) for MAKE30 and 0.759 (95% CI 0.654–0.864) for 90-day adverse outcomes. A web-based risk calculator can facilitate the application of the XGBoost models in daily clinical practice. In conclusion, XGBoost showed good performance in predicting MAKE30 and 90-day adverse outcomes, which provided clinicians with useful tools for prognostic assessment in hospitalized AKI children.

Combining adult with pediatric patient data to develop a clinical decision support tool intended for children: leveraging machine learning to model heterogeneity

Background

Clinical decision support (CDS) tools built using adult data do not typically perform well for children. We explored how best to leverage adult data to improve the performance of such tools. This study assesses whether it is better to build CDS tools for children using data from children alone or to use combined data from both adults and children.

Methods

Retrospective cohort using data from 2017 to 2020. Participants include all individuals (adults and children) receiving an elective surgery at a large academic medical center that provides adult and pediatric services. We predicted need for mechanical ventilation or admission to the intensive care unit (ICU). Predictor variables included demographic, clinical, and service utilization factors known prior to surgery. We compared predictive models built using machine learning to regression-based methods that used a pediatric or combined adult-pediatric cohort. We compared model performance based on Area Under the Receiver Operator Characteristic.

Results

While we found that adults and children have different risk factors, machine learning methods are able to appropriately model the underlying heterogeneity of each population and produce equally accurate predictive models whether using data only from pediatric patients or combined data from both children and adults. Results from regression-based methods were improved by the use of pediatric-specific data.

Conclusions

CDS tools for children can successfully use combined data from adults and children if the model accounts for underlying heterogeneity, as in machine learning models.

Update on prognosis driven classification of pediatric AKI

Acute kidney injury (AKI) affects a large proportion of hospitalized children and increases morbidity and mortality in this population. Initially thought to be a self-limiting condition with uniformly good prognosis, we now know that AKI can persist and progress to acute kidney disease (AKD) and chronic kidney disease (CKD). AKI is presently categorized by stage of injury defined by increase in creatinine, decrease in eGFR, or decrease in urine output. These commonly used biomarkers of acute kidney injury do not change until the injury is well established and are unable to detect early stage of the disease when intervention is likely to reverse injury. The kidneys have the ability to compensate and return serum creatinine to a normal or baseline level despite nephron loss in the setting of AKI possibly masking persistent dysfunction. Though these definitions are important, classifying children by their propensity for progression to AKD and CKD and defining these risk strata by other factors besides creatinine may allow for better prognosis driven discussion, expectation setting, and care for our patients. In order to develop a classification strategy, we must first be able to recognize children who are at risk for AKD and CKD based on modifiable and non-modifiable factors as well as early biomarkers that identify their risk of persistent injury. Prevention of initial injury, prompt evaluation and treatment if injury occurs, and mitigating further injury during the recovery period may be important factors in decreasing risk of AKD and CKD after AKI. This review will cover presently used definitions of AKI, AKD, and CKD, recent findings in epidemiology and risk factors for AKI to AKD to CKD progression, novel biomarkers for early identification of AKI and AKI that may progress to CKD and future directions for improving outcome in children with AKI.

Efficacy and Safety of NSAIDs in Infants: A Comprehensive Review of the Literature of the Past 20 Years

Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly used in infants, children, and adolescents worldwide; however, despite sufficient evidence of the beneficial effects of NSAIDs in children and adolescents, there is a lack of comprehensive data in infants. The present review summarizes the current knowledge on the safety and efficacy of various NSAIDs used in infants for which data are available, and includes ibuprofen, dexibuprofen, ketoprofen, flurbiprofen, naproxen, diclofenac, ketorolac, indomethacin, niflumic acid, meloxicam, celecoxib, parecoxib, rofecoxib, acetylsalicylic acid, and nimesulide. The efficacy of NSAIDs has been documented for a variety of conditions, such as fever and pain. NSAIDs are also the main pillars of anti-inflammatory treatment, such as in pediatric inflammatory rheumatic diseases. Limited data are available on the safety of most NSAIDs in infants. Adverse drug reactions may be renal, gastrointestinal, hematological, or immunologic. Since NSAIDs are among the most frequently used drugs in the pediatric population, safety and efficacy studies can be performed as part of normal clinical routine, even in young infants. Available data sources, such as (electronic) medical records, should be used for safety and efficacy analyses. On a larger scale, existing data sources, e.g. adverse drug reaction programs/networks, spontaneous national reporting systems, and electronic medical records should be assessed with child-specific methods in order to detect safety signals pertinent to certain pediatric age groups or disease entities. To improve the safety of NSAIDs in infants, treatment needs to be initiated with the lowest age-appropriate or weight-based dose. Duration of treatment and amount of drug used should be regularly evaluated and maximum dose limits and other recommendations by the manufacturer or expert committees should be followed. Treatment for non-chronic conditions such as fever and acute (postoperative) pain should be kept as short as possible. Patients with chronic conditions should be regularly monitored for possible adverse effects of NSAIDs.

Frequency of Drug Induced Acute Kidney Injury in Pediatric Intensive Care Unit

Background: Acute kidney injury (AKI) is known to complicate one-third of cases in pediatric intensive care units (PICU), and almost one-fourth of these are due to nephrotoxic drugs (NTDs). Although stopping NTDs seems the most obvious option, it is not practically applicable. Many NTDs are the only existing option, and their potential benefits outweigh the risk of drug-induced AKI.

Objectives: To assess the proportion of children receiving NTDs in the PICU and highlight the children who developed AKI.

Methods: A prospective observational study was conducted in the PICU of the National Institute of Child Health, Karachi. All children admitted to the PICU for at least 72 hours not diagnosed with any acute or chronic kidney disease were included. Serum creatinine (SCr) was done at admission and then after 72 hours. Data was entered and analyzed using IBM Corp. Released 2013. IBM SPSS Statistics for Windows, Version 22.0. Armonk, NY: IBM Corp.

Results: Of 99 children, 53 (53.5%) were male. NTD exposure was positive in 97 (97.9%), and 72 (72.7%) had high exposure (≥3 NTDs). Drug-induced AKI was diagnosed in 46 (46.5%). It was significantly related to high SCr even at admission and high NTDs exposure. The mortality rate in the AKI group was 17% compared to 4% in the non-AKI (p=0.02).

Conclusion: Almost half of all PICU admissions were infants. Almost all patients were exposed to NTDs, and three-fourth experienced high exposure. AKI developed in 46% of patients and may be predicted by raised creatinine at the time of admission. Children exposed to ≥3 NTDs had a higher chance of drug-induced AKI.

Controversies in paediatric acute kidney injury and continuous renal replacement therapy: can paediatric care lead the way to precision acute kidney injury medicine?

PURPOSE OF REVIEW

Paediatric patients represent a unique challenge for providers managing acute kidney injury (AKI). Critical care for these children requires a precise approach to assessment, diagnostics and management.

RECENT FINDINGS

Primarily based on observational data, large epidemiologic datasets have demonstrated a strong association between AKI prevalence (one in four critically ill children) and poor patient outcome. Drivers of AKI itself are multifactorial and the causal links between AKI and host injury remain incompletely defined, creating a management paradigm primarily supportive in nature. The previous decades of research have focused primarily on elucidating the population-level epidemiologic signal of AKI and use of renal replacement therapy (RRT), but in order to reverse the course of the AKI 'epidemic', future decades will require more attention to the individual patient. A patient-level approach to AKI in children will require sophisticated approaches to risk stratification, diagnostics and targeted utilization of therapies (both supportive and targeted towards drivers of injury).

SUMMARY

In this review, we will summarize the past, present and future of AKI care in children, discussing the ongoing work and future goals of a personalized approach to AKI medicine.

Acute pediatric kidney replacement therapies in Europe: demographic results from the EurAKId Registry

BACKGROUND

Acute kidney injury (AKI), particularly that requiring dialysis, is a severe complication in hospitalized children associated with high morbidity and mortality. A prospective European AKI registry (EurAKId registry, NCT02960867) was created to describe the epidemiology and outcomes of pediatric patients treated with acute dialysis.

METHODS

Children were recruited who were between 0 and 18 years of age and were treated both in and outside the Pediatric Intensive Care Unit (PICU) with peritoneal dialysis (PD), hemodialysis (HD) or continuous kidney replacement therapy (CKRT) for AKI or metabolic derangement, fluid overload (FO), sepsis, or respiratory distress. Five age groups and 12 categories of primary diseases were defined.

RESULTS

Data on 340 patients were analyzed, of whom 86% received dialysis for AKI and 14% for reasons other than AKI. Boys accounted for 60% of the patients. Illness severity was greater in children with cardiac and hematologic diseases than those with kidney diseases. Most patients received dialysis in the PICU (84%). The most frequently used dialysis modality was CKRT (64%), followed by PD (14%) and HD (14%). The overall survival rate was 65%. Survival was significantly lower in children with three comorbidities than in children with no comorbidities (41% and 83%, p < 0.001).

CONCLUSIONS

The EurAKId registry is the first prospective registry considering pediatric acute kidney replacement therapies (KRT) in both critical and non-critical care settings, focusing on the three dialysis modalities in Europe. The clinical indications for KRT have expanded; our population was characterized by critically ill patients, primarily boys, who frequently received dialysis in the PICU with CKRT.

Proenkephalin as a new biomarker for pediatric acute kidney injury - reference values and performance in children under one year of age

Objectives Acute kidney injury (AKI) is common in critically ill children, but current biomarkers are suboptimal. Proenkephalin A 119-159 (PENK) is a promising new biomarker for AKI in adults, but pediatric data is lacking. We determined PENK reference intervals for healthy children, crucial for clinical implementation, and explored concentrations in critically ill infants aged under 1 year. Methods Observational cohort study in healthy infants and critically ill children aged 0-1 years. Reference values were determined using generalized additive models. Plasma PENK concentrations between healthy children and critically ill children with and without AKI, were compared using linear mixed modelling. The performance of PENK as AKI biomarker was compared to cystatin C (CysC) and β-trace protein (BTP) using receiver-operating-characteristic (ROC) analysis. Results PENK concentrations in 100 healthy infants were stable during the first year of life (median 517.3 pmol/L). Median PENK concentrations in 91 critically ill children, were significantly higher in those with AKI (n=40) (KDIGO Stage 1 507.9 pmol/L, Stage 2 704.0 pmol/L, Stage 3 930.5 pmol/L) than non-AKI patients (n=51, 432.2 pmol/L) (p < 0.001). PENK appeared to relate better to AKI diagnosis than CysC and BTP (AUROC PENK 0.858, CysC 0.770 and BTP 0.711) in the first 24 h after recruitment. Conclusions PENK reference values are much higher in young infants than adults, but clearly discriminate between children with and without AKI, with comparable or better performance than CysC and BTP. Our results illustrate the importance of establishing age-normalized reference values and indicate PENK as a promising pediatric AKI biomarker.

Trajectory of AKI in hospitalized pediatric patients - impact of duration and repeat events

BACKGROUND

Peak severity of acute kidney injury (AKI) is associated with mortality in hospitalized pediatric patients. Other factors associated with AKI, such as number of AKI events, severity of AKI events, and time spent in AKI may also have associations with mortality. Characterization of these events could help to evaluate patient outcomes.

METHODS

Pediatric inpatients (<19 years of age) from 2011-2019 who were not on maintenance renal replacement therapy and had least one serum creatinine (SCr) obtained during hospital admission were included. Percent change in SCr from the minimum value in the prior 7 days was used for AKI staging according to KDIGO criteria. Maximum value for age appropriate normal was used for patients with only one SCr. Repeat AKI events were classified in patients if KDIGO criteria was met more than once with at least one SCr value between episodes that did not meet KDIGO criteria.Patient demographics were summarized and incidence of AKI was determined along with associations with mortality. AKI characterizations for the admission were developed including: AKI, repeat (>1) AKI, AKI severity (maximum KDIGO stage), and total number of AKI events. AKI duration as percent admission days in a KDIGO stage and AKI percent velocity were determined. Kaplan-Meier analysis was performed for time to 30 day survival by AKI characterization. A mixed effects logistic regression model with mortality as the dependent variable and nested in patients was developed incorporating patient variables and AKI characterizations.

RESULTS

A total of 184,297 inpatient encounters met study criteria (male 51.7%, Age 7.8 years (IQR 2.5, 13.8), mortality 0.56%). Hospital length of stay was 1.9 days (IQR 0.37, 4.8 days), 15.4% had an intensive care unit admission and 12.2% underwent mechanical ventilation. AKI occurred in 5.6% (n = 10,246) of admissions (Stage I = 4.5% (n = 8,310), Stage II = 1.3% (n = 2,363), Stage III=0.77% (n = 1,423)) and repeat AKI events occurred in 1.92% (n = 3,558). AKI was associated with mortality (OR 6.0, 95% CI 4.8, 7.6, p < 0.001) and increasing severity (KDIGO maximum stage) was associated with increased mortality. Multiple AKI events were also associated with mortality (p < 0.001),. Duration of AKI was associated with mortality (p < 0.001) but AKI velocity was not (p > 0.05).

CONCLUSIONS

AKI occurs in 5.6% of the pediatric inpatient population and multiple AKI events occur in ∼30% of these patients. Maximum KDIGO stage is most strongly associated with mortality. Multiple AKI events and AKI duration should also be considered when evaluating patient outcomes.

Cumulative Application of Creatinine and Urine Output Staging Optimizes the Kidney Disease: Improving Global Outcomes Definition and Identifies Increased Mortality Risk in Hospitalized Patients With Acute Kidney Injury

OBJECTIVES

Acute kidney injury is diagnosed according to creatinine and urine output criteria. Traditionally, both are applied, and a severity stage (1-3) is conferred based upon the more severe of the two; information from the other criteria is discarded. Physiologically, however, rising creatinine and oliguria represent two distinct types of renal dysfunction. We hypothesized that using the information from both criteria would more accurately characterize acute kidney injury severity and outcomes.

DESIGN

Prospective cohort study.

SETTING

Multicenter, international collaborative of ICUs.

PATIENTS

Three thousand four hundred twenty-nine children and young adults admitted consecutively to ICUs as part of the Assessment of the Worldwide Acute Kidney Injury, Renal Angina and Epidemiology Study.

MEASUREMENTS AND MAIN RESULTS

The Kidney Disease: Improving Global Outcomes creatinine and urine output acute kidney injury criteria were applied sequentially, and the two stages were summed, generating an Acute Kidney Injury (AKI) Score ranging from 1 to 6. The primary outcome was 28-day mortality; secondary outcomes were time until ICU discharge and nonrecovery from acute kidney injury. Models considered associations with AKI Score, assessing the relationship unadjusted and adjusted for covariates. Twenty-eight-day mortality and nonrecovery from acute kidney injury were modeled using logistic regression. For 28-day ICU discharge, competing risks analysis was performed. Although AKI Scores 1-3 had similar mortality to no Acute Kidney Injury, AKI Scores 4-6 were associated with increased mortality. Relative to No Acute Kidney Injury, AKI Scores 1-6 were less likely to be discharged from the ICU within 28 days. Relative to AKI Score 1, AKI Scores 2-6 were associated with higher risk of nonrecovery. Within the traditional Kidney Disease: Improving Global Outcomes Stage 3 acute kidney injury cohort, when compared with AKI Score 3, AKI Scores 4-6 had increased mortality, AKI Scores 5-6 had prolonged time to ICU discharge, and AKI Score 6 experienced higher nonrecovery rates.

CONCLUSIONS

Cumulative application of the creatinine and urine output criteria characterizes renal excretory and fluid homeostatic dysfunction simultaneously. This Acute Kidney Injury score more comprehensively describes the outcome implications of severe acute kidney injury than traditional staging methods.

Impact of integrated clinical decision support systems in the management of pediatric acute kidney injury: a pilot study

BACKGROUND

Acute kidney injury (AKI) is common but not often recognized. Early recognition and management may improve patient outcomes.

METHODS

This is a prospective, nonrandomized study of clinical decision support (CDS) system [combining electronic alert and standardized care pathway (SCP)] to evaluate AKI detection and progression in hospitalized children. The study was done in three phases: pre-, intervention (CDS) and post. During CDS, text-page with AKI stage and link to SCP was sent to patient's contact provider at diagnosis of AKI using creatinine. The SCP provided guidelines on AKI management [AEIOU: Assess cause of AKI, Evaluate drug doses, Intake-Output charting, Optimize volume status, Urine dipstick].

RESULTS

In all, 239 episodes of AKI in 225 patients (97 females, 43.1%) were analyzed. Proportion of patients with decrease in the stage of AKI after onset was 71.4% for CDS vs. 64.4% for pre- and 55% for post-CDS phases (p = 0.3). Documentation of AKI was higher during CDS (74.3% CDS vs. 47.5% pre- and 57.5% post-, p < 0.001). Significantly greater proportion of patients had nephrotoxic medications adjusted, or fluid plan changed during CDS. Patients from CDS phase had higher eGFR at discharge and at follow-up.

CONCLUSIONS

AKI remains under-recognized. CDS (electronic alerts and SCP) improve recognition and allow early intervention. This may improve long-term outcomes, but larger studies are needed.

IMPACT

Acute kidney injury can cause significant morbidity and mortality. It is under-recognized in children. Clinical decision support can be used to leverage existing data in the electronic health record to improve AKI recognition. This study demonstrates the use of a novel, electronic health record-linked, clinical decision support tool to improve the recognition of AKI and guideline-adherent clinical care.

Acute Kidney Injury and Outcomes in Children Undergoing Noncardiac Surgery: A Propensity-Matched Analysis

BACKGROUND

Acute kidney injury (AKI) has been well documented in adults after noncardiac surgery and demonstrated to be associated with adverse outcomes. We report the prevalence of AKI after pediatric noncardiac surgery, the perioperative factors associated with postoperative AKI, and the association of AKI with postoperative outcomes in children undergoing noncardiac surgery.

METHODS

Patients ≤18 years of age who underwent noncardiac surgery with serum creatinine during the 12 months preceding surgery and no history of end-stage renal disease were included in this retrospective observational study at a single tertiary academic hospital. Patients were evaluated during the first 7 days after surgery for development of any stage of AKI, according to Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Patients were classified into stages of KDIGO AKI for the purposes of describing prevalence. For further analyses, patients were grouped into those who developed any stage of AKI postoperatively and those who did not. Additionally, the time point at which each patient was first diagnosed with stage I AKI or greater was also assessed. Pre-, intra-, and postoperative factors were compared between the 2 groups. A multivariable Cox proportional hazards regression model was created to examine the time to first diagnosis of AKI using all nonredundant covariates. Analysis of the association of AKI with postoperative outcomes, mortality and 30-day readmission, was undertaken utilizing propensity score-matched controls and a multivariable Cox proportional hazards regression model.

RESULTS

A total of 25,203 cases between 2013 and 2018 occurred; 8924 met inclusion criteria. Among this cohort, the observed prevalence of postoperative AKI was 3.2% (288 cases; confidence interval [CI], 2.9-3.6). The multivariable Cox model showed American Society of Anesthesiologists (ASA) status to be associated with the development of postoperative AKI. Several other factors, including intraoperative hypotension, were significantly associated with postoperative AKI in univariable models but found not to be significantly associated after adjustment. The multivariable Cox analyses with propensity-matched controls showed an estimated hazard ratio of 3.28 for mortality (CI, 1.71-6.32, P < .001) and 1.55 for 30-day readmission (CI, 1.08-2.23, P = .018) in children who developed AKI versus those who did not.

CONCLUSIONS

In children undergoing noncardiac surgery, postoperative AKI occurred in 3.2% of patients. Several factors, including intraoperative hypotension, were significantly associated with postoperative AKI in univariable models. After adjustment, only ASA status was found to be significantly associated with AKI in children after noncardiac surgery. Postoperative AKI was found to be associated with significantly higher rates of mortality and 30-day readmission in multivariable, time-varying models with propensity-matched controls.

ISPD guidelines for peritoneal dialysis in acute kidney injury: 2020 Update (paediatrics)

SUMMARY OF RECOMMENDATIONS

1.1 Peritoneal dialysis is a suitable renal replacement therapy modality for treatment of acute kidney injury in children. (1C)2. Access and fluid delivery for acute PD in children.2.1 We recommend a Tenckhoff catheter inserted by a surgeon in the operating theatre as the optimal choice for PD access. (1B) (optimal)2.2 Insertion of a PD catheter with an insertion kit and using Seldinger technique is an acceptable alternative. (1C) (optimal)2.3 Interventional radiological placement of PD catheters combining ultrasound and fluoroscopy is an acceptable alternative. (1D) (optimal)2.4 Rigid catheters placed using a stylet should only be used when soft Seldinger catheters are not available, with the duration of use limited to <3 days to minimize the risk of complications. (1C) (minimum standard)2.5 Improvised PD catheters should only be used when no standard PD access is available. (practice point) (minimum standard)2.6 We recommend the use of prophylactic antibiotics prior to PD catheter insertion. (1B) (optimal)2.7 A closed delivery system with a Y connection should be used. (1A) (optimal) A system utilizing buretrols to measure fill and drainage volumes should be used when performing manual PD in small children. (practice point) (optimal)2.8 In resource limited settings, an open system with spiking of bags may be used; however, this should be designed to limit the number of potential sites for contamination and ensure precise measurement of fill and drainage volumes. (practice point) (minimum standard)2.9 Automated peritoneal dialysis is suitable for the management of paediatric AKI, except in neonates for whom fill volumes are too small for currently available machines. (1D)3. Peritoneal dialysis solutions for acute PD in children3.1 The composition of the acute peritoneal dialysis solution should include dextrose in a concentration designed to achieve the target ultrafiltration. (practice point)3.2  Once potassium levels in the serum fall below 4 mmol/l, potassium should be added to dialysate using sterile technique. (practice point) (optimal) If no facilities exist to measure the serum potassium, consideration should be given for the empiric addition of potassium to the dialysis solution after 12 h of continuous PD to achieve a dialysate concentration of 3-4 mmol/l. (practice point) (minimum standard)3.3  Serum concentrations of electrolytes should be measured 12 hourly for the first 24 h and daily once stable. (practice point) (optimal) In resource poor settings, sodium and potassium should be measured daily, if practical. (practice point) (minimum standard)3.4  In the setting of hepatic dysfunction, hemodynamic instability and persistent/worsening metabolic acidosis, it is preferable to use bicarbonate containing solutions. (1D) (optimal) Where these solutions are not available, the use of lactate containing solutions is an alternative. (2D) (minimum standard)3.5  Commercially prepared dialysis solutions should be used. (1C) (optimal) However, where resources do not permit this, locally prepared fluids may be used with careful observation of sterile preparation procedures and patient outcomes (e.g. rate of peritonitis). (1C) (minimum standard)4. Prescription of acute PD in paediatric patients4.1 The initial fill volume should be limited to 10-20 ml/kg to minimize the risk of dialysate leakage; a gradual increase in the volume to approximately 30-40 ml/kg (800-1100 ml/m²) may occur as tolerated by the patient. (practice point)4.2 The initial exchange duration, including inflow, dwell and drain times, should generally be every 60-90 min; gradual prolongation of the dwell time can occur as fluid and solute removal targets are achieved. In neonates and small infants, the cycle duration may need to be reduced to achieve adequate ultrafiltration. (practice point)4.3 Close monitoring of total fluid intake and output is mandatory with a goal to achieve and maintain normotension and euvolemia. (1B)4.4 Acute PD should be continuous throughout the full 24-h period for the initial 1-3 days of therapy. (1C)4.5  Close monitoring of drug dosages and levels, where available, should be conducted when providing acute PD. (practice point)5. Continuous flow peritoneal dialysis (CFPD)5.1   Continuous flow peritoneal dialysis can be considered as a PD treatment option when an increase in solute clearance and ultrafiltration is desired but cannot be achieved with standard acute PD. Therapy with this technique should be considered experimental since experience with the therapy is limited. (practice point) 5.2  Continuous flow peritoneal dialysis can be considered for dialysis therapy in children with AKI when the use of only very small fill volumes is preferred (e.g. children with high ventilator pressures). (practice point).

For Whom the Bell Tolls: Acute Kidney Injury and Electronic Alerts for the Pediatric Nephrologist

With the advent of the electronic medical record, automated alerts have allowed for improved recognition of patients with acute kidney injury (AKI). Pediatric patients have the opportunity to benefit from such alerts, as those with a diagnosis of AKI are at risk of developing long-term consequences including reduced renal function and hypertension. Despite extensive studies on the implementation of electronic alerts, their overall impact on clinical outcomes have been unclear. Understanding the results of these studies have helped define best practices in developing electronic alerts with the aim of improving their impact on patient care. As electronic alerts for AKI are applied to pediatric patients, identifying their strengths and limitations will allow for continued improvement in its use and efficacy.

Serum Creatinine Reference Limits in Pediatric Population-A Single Center Electronic Health Record-Based Database in Taiwan

Objective: To assess age- and sex-specific serum creatinine levels in a pediatric population using a hospital-based database in Taiwan. Study Design: Data on serum creatinine levels were obtained from the National Taiwan University Hospital-integrated Medical Database (NTUH-iMD). Due to the possibility of having acute kidney injury or chronic kidney disease, individuals with multiple serum creatinine measurements were excluded, and outliers in each age- and sex-specific group were also subsequently removed. The remaining creatinine measurements in each group were analyzed, and 95% reference limits were established. Results: Serum creatinine data of individuals aged between 1 month and 18 years from May 2011 to January 2018 were retrieved. After applying the exclusion criteria, 27,911 individuals with a single corresponding serum creatinine measurement were enrolled. Creatinine level reference limits for each age- and sex-specific group were generated. The upper reference limits (URLs), which are particularly useful in clinical practice, followed the natural trend of increasing serum creatinine with age. Conclusion: We generated serum creatinine reference limits from a single hospital-integrated medical database in Taiwan for different age- and sex-specific groups of children. Our results will aid physicians in clinical practice regarding renal function evaluation, especially for patients without a recent baseline serum creatinine level.

Pediatric Acute Kidney Injury to the Subsequent CKD Transition

BACKGROUND

Both acute kidney injury (AKI) and CKD are complex syndromes caused by multiple etiologies and presented with various degrees of severity. Studies on adults provide strong evidence that AKI is an independent risk factor for both the initiation and progression of CKD, and the severity, frequency, and duration of AKI are crucial factors in the subsequent development of CKD. However, without consensus definitions of AKI and CKD and long-term follow-up studies using predictive biomarkers, it is difficult to clarify the potential for transition from AKI to CKD in pediatric populations. The goal of this review is to describe the most recent studies in epidemiology of pediatric AKI and biomarkers aiding in the earlier detection of AKI and CKD.

SUMMARY

KDIGO criteria for AKI have been widely applied for pediatric AKI studies. AKI in critically ill and non-critically ill children is common. CKD is highly prevalent in pediatric AKI survivors. Compared with traditional biomarkers such as serum Cr, proteinuria, and estimated glomerular filtration rate, urinary biomarkers earlier identifying AKI may also detect CKD earlier, but additional studies are required to determine their clinical utility.

KEY MESSAGES

The use of consensus AKI criteria has improved our understanding of pediatric AKI epidemiology, and an association between AKI and CKD in pediatric populations has been endorsed. However, further studies are needed to better answer a definitive causal relationship between pediatric AKI and the subsequent development of CKD.

Acute kidney injury following intravenous acyclovir in children

OBJECTIVE

The objective of this study was to describe the incidence of acute kidney injury (AKI) in children receiving intravenous acyclovir and determine risk factors that may be associated with it.

DESIGN

This was a retrospective cohort study, conducted by chart review.

SETTING

The study was conducted across two paediatric hospitals.

PATIENTS

All inpatients that received intravenous acyclovir in records from January 2015 to December 2015 were reviewed. Only patients with creatinine measurements taken before and after starting acyclovir were included in the study.

MAIN OUTCOME MEASURES

The main outcome measure was the development of AKI following intravenous acyclovir administration, with AKI defined according to change in serum creatinine.

RESULTS

150 patients were included in the analysis. Patients' ages ranged from 2 days to 18.6 years. 27 children (18%) developed at least stage 1 AKI. Children receiving cancer treatment developed AKI more frequently than children with other diagnoses; 29.3% vs 10.9% (OR 3.4, 95% CI 1.5 to 8.2, p=0.008). The baseline estimated glomerular filtration rate (eGFR) was higher in those children who developed AKI. 34% of children had an eGFR >120 mL/min/1.73 m² prior to acyclovir use. 31% of these children developed AKI compared with only 11% of those with a normal baseline eGFR (OR 3.6, 95 CI 1.3 to 10.1, p=0.02). Baseline eGFR was a significant predictor of AKI in a multivariable analysis that included cumulative dose and treatment duration (OR 1.02, p=0.013).

CONCLUSION

AKI following intravenous acyclovir exposure is common in children. This study raises the possibility that glomerular hyperfiltration is a previously unrecognised risk factor for acyclovir-induced AKI.

Prognostic Impact of Parameters of Metabolic Acidosis in Critically Ill Children with Acute Kidney Injury: A Retrospective Observational Analysis Using the PIC Database

Acute kidney injury (AKI) is a major complication of sepsis that induces acid-base imbalances. While creatinine levels are the only indicator for assessing the prognosis of AKI, prognostic importance of metabolic acidosis is unknown. We conducted a retrospective observational study by analyzing a large China-based pediatric critical care database from 2010 to 2018. Participants were critically ill children with AKI admitted to intensive care units (ICUs). The study included 1505 children admitted to ICUs with AKI, including 827 males and 678 females. The median age at ICU admission was 22 months (interquartile range 7–65). After a median follow-up of 10.87 days, 4.3% (65 patients) died. After adjusting for confounding factors, hyperlactatemia, low pH, and low bicarbonate levels were independently associated with 28-day mortality (respective odds ratio: 3.06, 2.77, 2.09; p values: <0.01, <0.01, <0.01). The infection had no interaction with the three parameters. The AKI stage negatively interacted with bicarbonate and pH but not lactate. The current study shows that among children with AKI, hyperlactatemia, low pH, and hypobicarbonatemia are associated with 28-day mortality.

Nephrotoxins and nephrotoxic acute kidney injury

Although the concept of nephrotoxicity has been recognized for more than 80 years, interest in nephrotoxins has intensified dramatically over the past two decades. Much of this attention has rightfully been focused on pharmaceutical agents and iatrogenic harm; however, it is important for providers to recognize that nephrotoxins can be found in naturally occurring substances as well. Although nephrotoxins exist in a myriad of forms, the means by which they induce injury can be organized into a few categories. For most of these agents, regardless of the mechanism, the final common pathway is acute kidney injury (AKI). Unfortunately, therapeutic options are limited and no treatments currently exist to reverse nephrotoxic AKI once it occurs. As a result, current strategies focus on increased awareness, nephrotoxin avoidance, early injury detection, and mitigation of disease severity. The goal of this review is to summarize our current understanding of nephrotoxic mechanisms and the epidemiology of nephrotoxic AKI. Additionally, avoidance and preventative strategies are discussed, screening approaches are suggested, and chronic monitoring recommendations are made.

Prediction of Acute Kidney Injury on Admission to Pediatric Intensive Care

OBJECTIVES

Up to 37% of children admitted to the PICU develop acute kidney injury as defined by Kidney Disease: Improving Global Outcomes criteria. We describe the prevalence of acute kidney injury in a mixed pediatric intensive care cohort using this criteria. As tools to stratify patients at risk of acute kidney injury on PICU admission are lacking, we explored the variables at admission and day 1 that might predict the development of acute kidney injury.

DESIGN

Single-center retrospective observational study.

SETTING

Thirty-six-bed surgical/medical tertiary PICU.

PATIENTS

Children from birth to less than or equal to 16 years old admitted between 2015 and 2018.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Clinical data were extracted from the PICU clinical information system. Patients with baseline creatinine at admission greater than 20 micromol/L above the calculated normal creatinine level were classified as "high risk of acute kidney injury." Models were created to predict acute kidney injury at admission and on day 1. Out of the 7,505 children admitted during the study period, 738 patients (9.8%) were classified as high risk of acute kidney injury at admission and 690 (9.2%) developed acute kidney injury during PICU admission. Compared to Kidney Disease: Improving Global Outcomes criteria as the reference standard, high risk of acute kidney injury had a lower sensitivity and higher specificity compared with renal angina index greater than or equal to 8 on day 1. For the admission model, the adjusted odds ratio of developing acute kidney injury for high risk of acute kidney injury was 4.2 (95% CI, 3.3-5.2). The adjusted odds ratio in the noncardiac cohort for high risk of acute kidney injury was 7.3 (95% CI, 5.5-9.7). For the day 1 model, odds ratios for high risk of acute kidney injury and renal angina index greater than or equal to 8 were 3.3 (95% CI, 2.6-4.2) and 3.1 (95% CI, 2.4-3.8), respectively.

CONCLUSIONS

The relationship between high risk of acute kidney injury and acute kidney injury needs further evaluation. High risk of acute kidney injury performed better in the noncardiac cohort.

Community-Based Epidemiology of Hospitalized Acute Kidney Injury

BACKGROUND

Acute kidney injury (AKI) may lead to short- and long-term consequences in children, but its epidemiology has not been well described at a population level and outside of ICU settings.

METHODS

In a large, diverse pediatric population receiving care within an integrated health care delivery system between 2008 and 2016, we calculated age- and sex-adjusted incidences of hospitalized AKI using consensus serum creatinine (SCr)-based diagnostic criteria. We also investigated the proportion of AKI detected in non-ICU settings and the rates of follow-up outpatient SCr testing after AKI hospitalization.

RESULTS

Among 1 500 546 children, the mean age was 9.8 years, 49.0% were female, and 33.1% were minorities. Age- and sex-adjusted incidence of hospitalized AKI among the entire pediatric population did not change significantly across the study period, averaging 0.70 (95% confidence interval: 0.68-0.73) cases per 1000 person-years. Among the subset of hospitalized children, the adjusted incidence of AKI increased from 6.0% of hospitalizations in 2008 to 8.8% in 2016. Approximately 66.7% of AKI episodes were not associated with an ICU stay, and 54.3% of confirmed, unresolved Stage 2 or 3 AKI episodes did not have outpatient follow-up SCr testing within 30 days postdischarge.

CONCLUSIONS

Community-based pediatric AKI incidence was ∼1 per 1000 per year, with two-thirds of cases not associated with an ICU stay and more than one-half not receiving early outpatient follow-up kidney function testing. Further efforts are needed to increase the systematic recognition of AKI in all inpatient settings with appropriate, targeted postdischarge kidney function monitoring and associated management.

Acute Kidney Injury: Diagnosis and Management

Pediatric medicine is growing in complexity and an increasing number of children with co-morbidities are exposed to potential renal damage. Initially ill-defined and thought to be mostly a transient phenomenon in children, acute kidney injury (AKI) has now emerged as a complex clinical syndrome independently associated with increased mortality and morbidity, including the development of chronic renal sequelae. Recent advances in molecular nephrology have better elucidated the early phase of AKI, where evidence of renal tissue damage is associated with adverse outcomes even without decrease in glomerular filtration rate, illustrating the flaws of the old paradigm based solely on an insensitive filtration marker, the serum creatinine. Prevention, prompt evaluation and early interventions are of essence to decrease AKI incidence and severity. Emerging data reveal that AKI is commonly encountered in hospitalized children, especially critically ill ones, hence the importance for all clinicians to be able to identify high risk patients, recognize AKI early and be comfortable with the initial medical management. In recent years, significant advances have been made in AKI definition and prediction, allowing early preventive measures in high risk children that are now proven to reduce AKI incidence. This review covers recent advances in the diagnosis, risk stratification, prevention and management of AKI in children.

Acute kidney injury without previous renal disease in critical care unit

BACKGROUND

Acute kidney injury (AKI) is common in hospitalized and critically ill children. Apart from primary kidney disease, etiologies of AKI are usually related to systemic disease and nephrotoxic insult. This study examines the incidence, characteristics, and mortality risks of AKI in critically ill children without primary renal disease or previously known chronic kidney disease.

METHODS

A retrospective cohort study was conducted of patients aged 1-18 years, diagnosed with AKI (excluding severe glomerulonephritis and previously known chronic kidney disease) in pediatric intensive care units between 2013 and 2016. Acute kidney injury was defined according to the Kidney Disease Improving Global Outcomes classifications. Cox proportional hazards regression analysis was employed to assess the relationship between the risk factors and mortality.

RESULTS

Of 1,377 pediatric intensive care unit patients, 253 (18.4%) developed AKI and only 169 (12.3%) who did not have previously known renal disease were included. Of these 169 AKI patients, the mean age was 8.1 ± 4.7 years; 88 (52.1%) patients were male; and 60 (35.5%) patients had AKI stage 3. The most common etiologies of AKI were sepsis (76.9%) and shock (64.5%). Fifty-three (31.4%) of those patients died during admission. The risk factors for death were the need for mechanical ventilation (adjusted hazard ratio, 17.82; 95% CI, 2.41-132.06) and AKI stage 3 (adjusted hazard ratio, 2.32; 95% CI, 1.07-5.00).

CONCLUSIONS

Acute kidney injury in critically ill children without previously known renal disease was approximately two-thirds of the overall incidence. The risk factors of in-hospital death were the use of mechanical ventilation, and AKI stage 3.

Clinical characteristics of acute glomerulonephritis with presentation of nephrotic syndrome at onset in children

BACKGROUND

Acute glomerulonephritis (AGN) is a common disease in children, which places a huge burden on developing countries. The prognosis of it may not always be good. However, the clinical characteristics of AGN with nephrotic syndrome (NS) at onset have not been fully clarified.

METHODS

One hundred and thirteen cases were analyzed retrospectively. Clinical data, pathological results and prognosis between AGN with NS (AGN-NS) and AGN without NS (AGN-no-NS) were compared.

RESULTS

Twenty (17.7%) of 113 patients were AGN-NS. The patients with AGN-NS were more likely to have hypertension (55.0% vs. 25.8%) and acute kidney injury (AKI) (50.0% vs. 17.2%). AKI was significantly related to the manifestation of AGN-NS in children (OR = 3.812, P = 0.040). Compared with the AGN-no-NS, the immunosuppressive treatments were more common in AGN-NS. A more severe pathological grade was significantly related to lower C3 fraction, estimated glomerular filtration rate (eGFR), and AKI, but not to the performance of AGN-NS. There was no difference in prognosis between the two groups.

CONCLUSIONS

AKI was significantly associated with AGN-NS. The prognosis of AGN-NS and AGN-no-NS in our study was almost good. Given the fact that AGN-NS patients are more likely to use immunosuppressive therapy, the long-term outcome of AGN-NS warrants further research.

Racial and health insurance disparities in pediatric acute kidney injury in the USA

BACKGROUND

Acute kidney injury (AKI) significantly increases morbidity and mortality for hospitalized children, yet sociodemographic risk factors for pediatric AKI are poorly described. We examined sociodemographic differences in pediatric AKI amongst a national cohort of hospitalized children.

METHODS

Secondary analysis of the most recent (2012) Kids' Inpatient Database (KID) from the Agency for Healthcare Research and Quality. Study sample weights were used to obtain national estimates of AKI (defined by administrative data). KID is a nationally representative sample of pediatric discharges throughout the USA. Linear risk regression models were used to assess the relationship between our primary exposures (race/ethnicity, health insurance, household urbanization, gender, and age) and the diagnosis of AKI, adjusting for comorbidities.

RESULTS

A total of 1,699,841 hospitalizations met our study criteria. In 2012, AKI occurred in approximately 12.3/1000 pediatric hospitalizations, which translates to almost 30,000 children nationally. Asian/Pacific Islander, African-American, and Hispanic children were at slightly increased risk for AKI compared to Caucasian children (adjusted risk difference (RD) 4.5 per 1000 hospitalizations, 95% confidence interval (CI) 2.9-6.0; 2.5/1000 hospitalizations, 95% CI 1.7-3.3; and 1.7/1000 hospitalizations, 95% CI 0.9-2.5, respectively). Uninsured children were more likely to suffer AKI compared to children with any health insurance (e.g., no insurance versus Medicaid: adjusted RD 14.4/1000 hospitalizations, 95% CI 12.7-16.2). Based on these national estimates, one episode of AKI might be prevented if 70 (95% CI 62-79) hospitalized children without insurance were provided with Medicaid.

CONCLUSIONS

Pediatric AKI occurs more frequently in racial minority and uninsured children, factors linked to lower socioeconomic status.

Long-term complications of acute kidney injury in children

PURPOSE OF REVIEW

The current review will describe the current evidence and mechanisms of acute kidney injury (AKI) as a risk factor for long-term kidney complications, summarize the rationale for AKI follow-up and present an approach to monitoring children with AKI. Despite emerging evidence linking AKI with risk for long-term kidney and cardiovascular outcomes, many children who develop AKI are not followed for kidney disease development after hospital discharge. Better understanding of long-term complications after AKI and practical algorithms for follow-up will hopefully increase the rate and quality of post-AKI monitoring.

RECENT FINDINGS

Recent evidence shows that pediatric AKI is associated with long-term renal outcomes such as chronic kidney disease (CKD) and hypertension, both known to increase cardiovascular risk. The mechanism of AKI progression to CKD involves maladaptive regeneration of tubular epithelial and endothelial cells, inflammation, fibrosis and glomerulosclerosis. Many AKI survivors are not followed, and no guidelines for pediatric AKI follow-up have been published.

SUMMARY

Children who had AKI are at increased risk of long-term renal complications but many of them are not monitored for these complications. Recognizing long-term outcomes post-AKI and integration of follow-up programs may have a long-lasting positive impact on patient health.

Acute Kidney Injury in Children Hospitalized With Diarrheal Illness in the United States

OBJECTIVES

To determine the incidence, correlates, and consequences of acute kidney injury (AKI) among children hospitalized with diarrheal illness in the United States.

METHODS

Using data from Kids' Inpatient Database in 2009 and 2012, we studied children hospitalized with a primary diagnosis of diarrheal illness (weighted N = 113 195). We used the International Classification of Diseases, Ninth Revision, Clinical Modification, diagnosis codes 584.5 to 584.9 to capture AKI. We calculated the incidence, correlates, and consequences (mortality, length of stay [LOS], and costs) of AKI associated with hospitalized diarrheal illness using stepwise logistic regression and generalized linear models.

RESULTS

The average incidence of AKI in children hospitalized with diarrheal illness was 0.8%. Hospital location and teaching status were associated with the odds of AKI, as were older age, solid organ transplant, hypertension, chronic kidney disease, and rheumatologic and hematologic conditions. The development of AKI in hospitalized diarrheal illness was associated with an eightfold increase in the odds of in-hospital mortality (odds ratio 8.0; 95% confidence interval [CI] 4.2-15.4). AKI was associated with prolonged LOS (mean increase 3.0 days; 95% CI 2.3-3.8) and higher hospital cost (mean increase $9241; 95% CI $4661-$13 820).

CONCLUSIONS

Several demographic factors and comorbid conditions are associated with the risk of AKI in children hospitalized with diarrheal illness. Although rare, development of AKI in this common pediatric condition is associated with increased mortality, LOS, and hospital cost.

Acute Kidney Injury in Children Based on Electronic Alerts

OBJECTIVE

To define the incidence and outcome of acute kidney injury (AKI) in pediatrics using data collected from a national electronic alert system.

STUDY DESIGN

A prospective national cohort study was undertaken to collect data on all cases of pediatric AKI, excluding neonates, identified by an e-alert, from April 2015 to March 2019.

RESULTS

There were 2472 alerts in a total of 1719 patients, giving an incidence of 77.3 per 100 000 person-years. Of the patients, 84.2% of all AKI were stage 1 and 58.3% occurred with a triggering creatinine within the reference range. The incidence of AKI was associated with measures of social deprivation. Thirty-day mortality was 1.7% but was significantly higher in hospital-acquired AKI (2.1%), compared with community-acquired AKI (0.8%, P < .001) and was associated with the severity of AKI at presentation. A significant proportion of patients had no repeat measure of creatinine (39.8%). This was higher in community-acquired AKI (69.7%) compared with hospital-acquired AKI (43.0%, P < .001), and higher in patients alerting with patients triggering with a creatinine within the reference range (48.4% vs 24.5%, P < .001). The majority of patients (84.7%) experienced only 1 AKI episode. Repeated episodes of AKI were associated with increased 30-mortaltiy (11.6% vs 4.6%, P < .001) and higher residual renal impairment (13.3% vs 5.4%, P < .001).

CONCLUSIONS

The results suggest that the significance of the alert is missed in many cases reflecting that a large proportion of cases represent modest elevations in serum creatinine (SCr), triggered by a SCr level that may be interpreted as being normal despite a significant increase from the baseline for the patient.

Impact of acute kidney injury and nephrotoxic exposure on hospital length of stay

OBJECTIVE

Acute kidney injury (AKI) is a common occurrence among hospitalized children and leads to increased mortality and prolonged length of stay (LOS) in critically ill patients. Few studies have examined the impact of AKI on LOS for common pediatric conditions. We hypothesized that a diagnosis of AKI would be associated with a longer hospital LOS and increased exposure to nephrotoxic medications for all patients.

PATIENTS AND METHODS

We performed a multicenter retrospective cross-sectional analysis of 34 children's hospitals in the Pediatric Health Information System (PHIS) database from 1/2009 through 12/2013. Patients were grouped based on primary discharge diagnosis, number of days spent in an intensive care unit, and assignment of a secondary diagnostic code for AKI. Median LOS was compared among different patient groupings. Exposure to commonly used nephrotoxic medications was collected for each admission.

RESULTS

A total of 588,884 admissions from 423,337 patients were included in the analysis. The median LOS among non-critically ill patients with and without AKI was 5 days [95% CI 3-10] versus 2 days [95% CI 1-4], respectively. Among critically ill patients, median LOS for those with and without AKI was 12 days [95% CI 7-20] versus 4 days [95% CI 2-7], respectively. Patients who developed AKI were more likely to have significant nephrotoxic exposure.

CONCLUSIONS

Development of AKI was associated with longer hospital length of stay and increased nephrotoxic medication exposure for all diagnostic categories. Non-critically ill children with AKI were hospitalized the same length or longer than critically ill children without AKI.

Evidence-based development of a nephrotoxic medication list to screen for acute kidney injury risk in hospitalized children

PURPOSE

Medications are commonly associated with acute kidney injury (AKI). However, in both clinical practice and research, consideration of specific medications as nephrotoxic varies widely. The Nephrotoxic Injury Negated by Just-in-time Action quality improvement collaborative was formed to focus on prevention or reduction of nephrotoxic medication-associated AKI in noncritically ill hospitalized children. However, there were discrepancies among institutions as to which medications should be considered nephrotoxic. The collaborative convened a Nephrotoxic Medication (NTMx) Subcommittee to develop a consensus for the classification of nephrotoxic medications.

SUMMARY

The NTMx Subcommittee initially included pediatric nephrologists, a pharmacist, and a pediatric intensivist. The committee reviewed NTMx lists from the collaborative and identified changes from the initial NTMx list. The NTMx Subcommittee conducted a literature review of the disputed medications and assigned an evidence grade based on the reported association with nephrotoxicity and the quality of the data. The association between medication exposure and AKI was also determined using administrative data from the Pediatric Health Information Systems database. The NTMx Subcommittee then came to a majority consensus regarding which medications should be included on the list. The subcommittee's recommendations were presented to the larger collaborative for approval, and consensus was achieved. The list continues to be reviewed and updated annually.

CONCLUSION

Formation of a multicenter quality-improvement initiative exposed current limitations as to which medications are considered nephrotoxic in clinical and research settings and presented an opportunity to approach this problem using an evidence-based process. A consensus definition of nephrotoxic-medication exposure was achieved.

Acute Kidney Injury in Hospitalized Pediatric Patients: A Review of Research

INTRODUCTION

Pediatric patients who develop acute kidney injury (AKI) while hospitalized have longer hospital stays, increased morbidity and mortality, and are at an increased risk for developing chronic kidney disease. Early recognition of AKI is becoming a major clinical focus. There is little research focusing on nursing interventions that may affect a pediatric patient's risk for developing AKI. The purpose of this review is to summarize reported predictors of AKI to improve its early recognition and treatment among hospitalized pediatric patients.

METHODS

A review of research was conducted to further identify risk factors of AKI among noncritically ill hospitalized pediatric patients.

RESULTS

The current literature demonstrated inconsistent findings in early recognition of AKI among hospitalized pediatric patients.

DISCUSSION

Interventions for early recognition and treatment of AKI should consider other variables, such as previous history of AKI and fluid status as risk factors, warranting additional research.