Acute Kidney Disease in Hospitalized Pediatric Patients With Acute Kidney Injury in China

Incidence of acute kidney injury-associated mortality in hospitalized children: a systematic review and meta-analysis

BACKGROUND

Acute kidney injury (AKI) is a significant health concern in hospitalized children and is associated with increased mortality. However, the true burden of AKI-associated mortality in pediatric populations remains unclear.

OBJECTIVE

To determine the pooled incidence of mortality independently associated with AKI in hospitalized children globally.

DATA SOURCES

Medline and Embase were searched for studies published by March 2024.

STUDY ELIGIBILITY CRITERIA

The inclusion criteria encompassed observational studies involving hospitalized pediatric patients (< 18 years old) with AKI. Only studies that identified AKI as an independent risk factor for increased mortality in multivariate analysis were considered.

STUDY APPRAISAL AND SYNTHESIS METHODS

Studies with at least 100 AKI patients were included in the meta-analysis. Two authors extracted data on the study and patients' characteristics and mortality across AKI stages and assessed the risk of bias. We used a random-effects meta-analysis to generate pooled estimates of mortality.

RESULTS

Analysis of 60 studies including 133,876 children with AKI revealed a pooled in-hospital mortality rate of 18.27% (95% CI: 14.89, 21.65). Mortality increased with AKI severity; 8.19% in stage 1, 13.44% in stage 2, and 27.78% in stage 3. Subgroup analyses showed no significant differences across geographical regions, income levels, or AKI definition criteria. The pooled post-discharge mortality rate was 6.84% (95% CI: 5.86, 7.82) in a 1-9-year follow-up period.

CONCLUSIONS

This meta-analysis demonstrates a substantial global burden of AKI-associated mortality in hospitalized children, with higher mortality rates in more severe AKI stages. These findings highlight the critical need for early detection and intervention strategies in pediatric AKI management.

CLINICAL TRIAL NUMBER

Not applicable.

Incidence and risk factors for acute kidney injury in children with nephrotic syndrome: a meta-analysis

Background

Nephrotic syndrome (NS) is a prevalent kidney disease in children. Acute kidney injury (AKI) is a severe complication of NS and has the potential to be life-threatening.

Objective

The aim of this study was to analyze the prevalence and risk factors of AKI in children with NS, and to provide an evidence-based medical basis for the early identification of high-risk children in the clinic.

Methods

A comprehensive search was conducted in publicly available databases, namely PubMed, Embase, Web of Science, Scopus, and the Cochrane Library, covering the period from the inception of each database until May 2024. The analysis involved examining basic characteristics (age, sex), the concomitant diseases (hypertension, infections), NS disease characteristics (steroid susceptibility classification, pathologic classification), laboratory test (e.g., serum albumin), and the use of nephrotoxic drugs. Traditional and network meta-analyses were performed for analysis.

Results

A total of 11 studies were included in the analysis, revealing an incidence of AKI of 29% (95% CI: 23%-37%). The analysis of factors indicated that the age of NS onset [standardized mean difference (SMD): 0.31; 95% confidence interval (CI): 0.08, 0.54; p = 0.009], sex [odds ratio (OR): 1.49; 95% CI: 1.03, 2.16; p = 0.035], serum albumin level (SMD: -0.43; 95% CI: -0.85, -0.02; p = 0.041), response to steroid treatment (OR: 0.52; 95% CI: 0.33, 0.80; p = 0.003), infection (OR: 3.60; 95% CI: 1.91, 6.78; p < 0.001), hypertension (OR: 4.02; 95% CI: 2.94, 5.51; p < 0.001), and nephrotoxic drug application (OR: 4.43; 95% CI: 1.86, 10.53; p = 0.001), were all significantly associated with the incidence of AKI. Furthermore, the results of the network meta-analysis suggested that the pathologic type of minor glomerular abnormalities (MGA)/diffuse mesangial proliferation (DMP), the type of infrequent relapses (IFRNS)/steroid-sensitive NS (SSNS), and the use of diuretic medications were associated with a relatively low risk of AKI occurrence.

Conclusion

Factors upon admission of children with NS are associated with the onset of AKI. Emphasis should be placed on populations with a heightened risk of AKI in clinical practice. Further research is warranted to confirm the findings due to the limitations of this study.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42024571170, PROSPERO (CRD42024571170).

Acute kidney disease in hospitalized pediatric patients: risk prediction based on an artificial intelligence approach

BACKGROUND

Acute kidney injury (AKI) and acute kidney disease (AKD) are prevalent among pediatric patients, both linked to increased mortality and extended hospital stays. Early detection of kidney injury is crucial for improving outcomes. This study presents a machine learning-based risk prediction model for AKI and AKD in pediatric patients, enabling personalized risk predictions.

METHODS

Data from 2,346 hospitalized pediatric patients, collected between January 2020 and January 2023, were divided into an 85% training set and a 15% test set. Predictive models were constructed using eight machine learning algorithms and two ensemble algorithms, with the optimal model identified through AUROC. SHAP was used to interpret the model, and an online prediction tool was developed with Streamlit to predict AKI and AKD.

RESULTS

The incidence of AKI and AKD were 14.90% and 16.26%, respectively. Patients with AKD combined with AKI had the highest mortality rate, at 6.94%, when analyzed by renal function trajectories. The LightGBM algorithm showed superior predictive performance for both AKI and AKD (AUROC: 0.813, 0.744). SHAP identified top predictors for AKI as serum creatinine, white blood cell count, neutrophil count, and lactate dehydrogenase, while key predictors for AKD included proton pump inhibitor, blood glucose, hemoglobin, and AKI grade.

CONCLUSION

The high incidence of AKI and AKD among hospitalized children warrants attention. Renal function trajectories are strongly associated with prognosis. Supported by a web-based tool, machine learning models can effectively predict AKI and AKD, facilitating early identification of high-risk pediatric patients and potentially improving outcomes.

Outcomes of acute kidney injury continuum in children

BACKGROUND

Acute kidney injury (AKI) is associated with high morbidity and mortality. The continuum of kidney damage after an AKI episode is poorly explored in the paediatric population.

METHODS

We performed a retrospective cohort study on 2346 children with AKI from a tertiary care hospital in Romania over a 9-year period. The main objective was to evaluate the impact of AKI duration on mortality and the risk of new-onset chronic kidney disease (CKD).

RESULTS

Out of 2346 AKI patients, transient AKI was present in 655 patients (27.9%), persistent AKI in 1009 children (43%) and acute kidney disease in 682 patients (29.1%). In contrast to transient AKI, children who developed acute kidney disease were younger, with a higher degree of anaemia, lower number of platelets, higher procalcitonin, higher LDH, higher GGT, higher urea and higher serum creatinine levels. The pre-renal cause of AKI was the leading cause regardless of AKI duration. As kidney injury progressed over time, there was an increasing incidence of the intrinsic causes of AKI (11.1% in transient AKI, 13.2% in persistent AKI and 22.6% in acute kidney disease). Acute kidney disease patients had the highest mortality rate (16.42%), followed by transient AKI (14.66%) and persistent AKI (9.81%). Overall mortality increased in the presence of renal microvascular alterations, acute tubular necrosis, lower haemoglobin, serum proteins and platelets, and higher procalcitonin levels.

CONCLUSIONS

The continuum of AKI expressed as acute kidney disease resulted in an increased risk of new-onset CKD. CKD was influenced by the intrinsic cause of AKI and not by AKI severity.

Acute Kidney Disease following Acute Kidney Injury in Children-A Retrospective Observational Cohort Study on Risk Factors and Outcomes

Background: Acute kidney disease (AKD) is a known risk factor for increased mortality and evolution towards chronic kidney disease (CKD) in adults. The data regarding AKD in children are scarce. The purpose of our study was to explore the risk factors for developing AKD based on exposures and susceptibilities in children with AKI doubled by the biological parameters from the first day of identified AKI. In addition, we followed the trajectory of AKD following an acute kidney injury (AKI) episode in children during hospital admission and after discharge with special considerations towards mortality and progression to new-onset CKD. Methods: We retrospectively evaluated 736 children, ages between 2 and 18 years old, with identified AKI during hospital admission in a tertiary care hospital from west Romania over a 9-year period. Results: AKD incidence following an AKI episode was 17%. Patients who developed AKD were older, with higher baseline serum creatinine, urea, C reactive protein and lower proteins, haemoglobin and sodium levels. In the adjusted model, no biological parameters influenced AKD development. Regarding certain exposures and personal susceptibilities in children with AKI, only anaemia independently increased the risk of AKD development by 2.47 times. However, out of the AKI causes, only the intrinsic causes of AKI independently increased the risk of progressing to AKD (glomerulonephritis by 4.94 and acute tubule-interstitial nephritis by 2.76 times). AKD increased the overall mortality by 2.6 times. The factors that independently increased the risk of CKD were AKD, acute tubular necrosis and higher baseline serum creatinine values. Conclusions: Only anaemia, glomerulonephritis and acute tubule-interstitial nephritis increased the risk of AKD development in children with AKI. AKD was an independent risk factor for mortality and new-onset CKD in children.

Pattern and prognostic factors for kidney function progression in survivors of children with acute kidney injury: a cohort study

OBJECTIVE

To examine the pattern of kidney function progression after acute kidney injury (AKI) and identify the associated risk factors.

DESIGN

A prospective cohort study was conducted from June 2020 to June 2021 on children aged 1 month to <18 years admitted to the paediatric intensive care unit (PICU). Acute kidney disease (AKD) was defined as AKI persisting from 7 to 90 days after diagnosis. The natural history and prognostic factors of kidney function progression were determined.

RESULTS

Among the 253 admissions with a median (IQR) age of 4.9 (9.7) years, the AKI and AKD incidence was 41.9% and 52.2% respectively. The incidence of estimated glomerular filtration rate (eGFR) <90 mL/min/1.73 m2 was 6.7% at 90 days and 11.9% at latest follow-up. Severe and prolonged AKI and higher degree of nephrotoxic medication exposure were associated with AKD development. The severity and duration of AKI and AKD significantly predicted kidney function non-recovery. Children with both entities exhibited a higher peak-to-baseline serum creatinine level ratio at 90 days (1.6 vs 1.0, p<0.001), and a more pronounced decline in eGFR (21% vs 19%, p=0.028) during the follow-up period compared with those without AKI/AKD. They also had an increased risk of having eGFR <90 mL/min/1.73 m2 at 90 days (HR 14.9 (95% CI 1.8 to 124.0)) and latest follow-up (HR 3.8 (95% CI 1.1 to 13.1)).

CONCLUSIONS

AKI and AKD are prevalent among critically ill children and pose substantial risk for non-recovery of kidney function among PICU survivors. A structural follow-up visit for AKI survivors to monitor kidney function progression is advocated.

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.

Kinetic Estimated Glomerular Filtration Rate in Predicting Paediatric Acute Kidney Disease

Kinetic estimation of glomerular filtration rate (KeGFR) has proved its utility in predicting acute kidney injury (AKI) in both adults and children. Our objective is to assess the clinical utility of KeGFR in predicting AKI severity and progression to acute kidney disease (AKD) in patients already diagnosed with AKI and to examine major adverse kidney events at 30 days (MAKE30). We retrospectively calculated the KeGFR within the first 24 h of identified AKI (KeGFR1) and in the 24 h prior to AKD (KeGFR2) in all admitted children under 18 years old. The cohort consisted of 803 patients with AKI. We proposed a new classification of KeGFR stages, from 1 to 5, and assessed the predictive value of KeGFR stages for AKD development and MAKE30. AKI severity was associated with lower KeGFRs. KeGFR1 and KeGFR2 predicted AKD with AUC values between 0.777 and 0.841 respectively, p < 0.001. KeGFR2 had the best performance in predicting MAKE30 (AUC of 0.819) with a sensitivity of 66.67% and specificity 87.7%. KeGFR1 stage 3, 4 and 5 increased the risk of AKD by 3.07, 6.56 and 28.07 times, respectively, while KeGFR2 stage 2, 3, 4 and 5 increased the risk of AKD 2.79, 3.58, 32.75 and 80.14 times. Stage 5 KeGFR1 and KeGFR2 stages 3, 4 and 5 increased the risk of MAKE30 by 7.77, 4.23. 5.89 and 69.42 times in the adjusted models. KeGFR proved to be a useful tool in AKI settings. KeGFR dynamics can predict AKI severity, duration and outcomes.

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

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

Etiology and outcomes of acute kidney disease in children: a cohort study

BACKGROUND

There is paucity of information regarding the etiology and outcomes of Acute Kidney Disease (AKD) in children.

METHODS

The objectives of this cohort study were to evaluate the etiology and outcomes of AKD; and analyze predictors of kidney survival (defined as free of CKD 2, 3a, 3b, 4 or 5). Patients aged 1 month to 18 years who developed AKD over a 4-year-period (January 2018-December 2021) were enrolled. Survivors were followed-up at the pediatric nephrology clinic, and screened for residual kidney injury.

RESULTS

Among 5710 children who developed AKI, 200 who developed AKD were enrolled. The median (IQR) eGFR was 17.03 (10.98, 28) mL/min/1.73 m². Acute glomerulonephritis, acute tubular necrosis (ATN), hemolytic uremic syndrome (HUS), sepsis-associated AKD, and snake envenomation comprised of 69 (34.5%), 39 (19.5%), 24 (12%), 23 (11.5%) and 15 (7.5%) of the patients respectively. Overall, 88 (44%) children required kidney replacement therapy (KRT). There were 37 (18.5%) deaths within the AKD period. At a follow-up of 90 days, 32 (16%) progressed to chronic kidney disease stage-G2 or greater. At a median (IQR) follow-up of 24 (6, 36.5) months (n = 154), 27 (17.5%) had subnormal eGFR, and 20 (12.9%) had persistent proteinuria and/or hypertension. Requirement of KRT predicted kidney survival (free of CKD 2, 3a, 3b, 4 or 5) in AKD (HR 6.7, 95% CI 1.2, 46.4) (p 0.04).

CONCLUSIONS

Acute glomerulonephritis, ATN, HUS, sepsis-associated AKD and snake envenomation were common causes of AKD. Mortality in AKD was 18.5%, and 16% progressed to CKD-G2 or greater at 90-day follow-up.

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.