Acute Kidney Injury in Children

Epidemiology, Risk Factors, and Clinical Outcomes of AKI in Pediatric Hematopoietic Stem Cell Transplant Patients

Key Points

The cumulative incidence of AKI diagnosis post–hematopoietic stem cell transplantation was 12.9%. Calcineurin inhibitor use was associated with the highest cumulative incidence, 21.6%, after hematopoietic stem cell transplantation. Patients with AKI with hypertension/hypertensive disease had a 30-day survival probability of 63.9% (hazard ratio, 4.86, 95% confidence interval, 3.58 to 6.60). Patients with AKI were 2.5 times more likely to experience composite hospitalization and/or mortality at 30 days. Of patients who developed AKI, dialysis dependence has nearly tripled since 2014.

Background

AKI is a common complication in pediatric patients undergoing hematopoietic stem cell transplantation (HSCT), with a reported prevalence ranging from 68% to 84%. Few multicenter pediatric studies comprehensively assess the epidemiologic associations and clinical outcomes associated with AKI development.

Methods

An observational, retrospective analysis was conducted using an aggregated electronic health record data platform. The study population consisted of pediatric patients (age <18 years) who underwent HSCT over a 20-year period. The study groups consisted of patients with an encounter diagnosis of AKI (n =713) and those without AKI (n =4455). Both groups were propensity matched for age, sex, race, prior cancer diagnosis, and other comorbidities. End points were incidence, mortality risk, clinical outcomes, and prevalence of dialysis dependence. Competing risks analysis, Cox proportional hazard analyses, Kaplan–Meier survival curves, and incidence/prevalence rates were calculated.

Results

After matching, 688 patients were identified. Cumulative incidence of AKI diagnosis post-HSCT was 13.7%. Hypertensive disease, calcineurin inhibitors, and vancomycin were the most prevalent risk factors for AKI, with calcineurin inhibitors showing the highest cumulative incidence (21.6%). Patients with AKI with hypertensive disease had a survival probability of 63.9% at 30 days, followed by calcineurin inhibitors (64.4%) and vancomycin (65.9%). Patients with AKI were 1.7 times more likely to experience composite hospitalization and/or mortality at 30 days. At 365 days post-HSCT, patients with AKI had higher rates of all-cause emergency department visits, intensive care unit admissions, and mechanical ventilation compared with non-AKI. Of patients who developed AKI, the prevalence of dialysis dependence has nearly tripled since 2014.

Conclusions

The findings highlight a strong association between specific risk factors, such as hypertension, calcineurin inhibitor use, and vancomycin use, with increased mortality and adverse clinical outcomes in patients with AKI after HSCT. These results emphasize the need for preventative actions such as 24-hour BP monitoring and discontinuation of potential nephrotoxic medications.

Acute kidney injury: the experience of a tertiary center of Pediatric Nephrology

INTRODUCTION

Acute kidney injury (AKI) is an abrupt deterioration of kidney function. The incidence of pediatric AKI is increasing worldwide, both in critically and non-critically ill settings. We aimed to characterize the presentation, etiology, evolution, and outcome of AKI in pediatric patients admitted to a tertiary care center.

METHODS

We performed a retrospective observational single-center study of patients aged 29 days to 17 years and 365 days admitted to our Pediatric Nephrology Unit from January 2012 to December 2021, with the diagnosis of AKI. AKI severity was categorized according to Kidney Disease Improving Global Outcomes (KDIGO) criteria. The outcomes considered were death or sequelae (proteinuria, hypertension, or changes in renal function at 3 to 6 months follow-up assessments).

RESULTS

Forty-six patients with a median age of 13.0 (3.5-15.5) years were included. About half of the patients (n = 24, 52.2%) had an identifiable risk factor for the development of AKI. Thirteen patients (28.3%) were anuric, and all of those were categorized as AKI KDIGO stage 3 (p < 0.001). Almost one quarter (n = 10, 21.7%) of patients required renal replacement therapy. Approximately 60% of patients (n = 26) had at least one sequelae, with proteinuria being the most common (n = 15, 38.5%; median (P25-75) urinary protein-to-creatinine ratio 0.30 (0.27-0.44) mg/mg), followed by reduced glomerular filtration rate (GFR) (n = 11, 27.5%; median (P25-75) GFR 75 (62-83) mL/min/1.73 m2).

CONCLUSIONS

Pediatric AKI is associated with substantial morbidity, with potential for proteinuria development and renal function impairment and a relevant impact on long-term prognosis.

Assessment of South Asian Pediatric Acute Kidney Injury: Epidemiology and Risk Factors (ASPIRE)-a prospective study on "severe dialysis dependent pediatric AKI"

BACKGROUND

Pediatric acute kidney injury (AKI) is a global health concern with an associated mortality risk disproportionately pronounced in resource-limited settings. There is a pertinent need to understand the epidemiology of pediatric AKI in vulnerable populations. Here, we proposed a prospective study to investigate the epidemiology and associated risk factors of "severe dialysis dependent AKI" in children among South Asian nations which would be the first and largest of its kind.

METHODS

The ASPIRE study (part of PCRRT-ICONIC Foundation initiative) is a multi-center, prospective observational study conducted in South Asian countries. All children and adolescents ≤ 18 years of age who required dialysis for AKI in any of the collaborating medical centers were enrolled. Data collection was performed until one of the following endpoints was observed: (1) discharge, (2) death, and (3) discharge against medical advice.

RESULTS

From 2019 to 2022, a total of 308 children with severe AKI were enrolled. The mean age was 6.17 years (63% males). Secondary AKI was more prevalent than primary AKI (67.2%), which predominantly occurred due to infections, dehydration, and nephrotoxins. Common causes of primary AKI were glomerulonephritis, hemolytic uremic syndrome, lupus nephritis, and obstructive uropathy. Shock, need for ventilation, and coagulopathy were commonly seen in children with severe AKI who needed dialysis. The foremost kidney replacement therapy used was peritoneal dialysis (60.7%). The mortality rate was 32.1%.

CONCLUSIONS

Common causes of AKI in children in South Asia are preventable. Mortality is high among these children suffering from "severe dialysis dependent AKI." Targeted interventions to prevent and identify AKI early and initiate supportive care in less-resourced nations are needed.

Editorial on the Special Issue "Advances in Pediatric Acute Kidney Injury"

Acute kidney injury (AKI) refers to a swift decline in kidney function, marked by the reduced excretion of waste products and disturbances in fluid and electrolyte balance [...].

Laboratory and clinical features of tumor lysis syndrome in children with non-Hodgkin lymphoma and evaluation of long-term renal functions in survivors

OBJECTIVE

The purpose of our study is to investigate the laboratory and clinical features of tumor lysis syndrome (TLS) and acute kidney injury (AKI) in childhood non-Hodgkin lymphomas (NHL) and to reveal their impact on long term kidney function in survivors.

METHODS

Our single-center retrospective study included 107 patients (0-18 years old) with NHL who were admitted and treated at our hospital between 1998 and 2020. The relationship between TLS and age, gender, histopathological subgroup, tumor stage, lactate dehydrogenase (LDH) level at presentation, bone marrow and kidney involvement were assessed. The long-term renal functions of the patients were investigated.

RESULTS

80.3% of the patients were male with a median age of 9.8 years. The most common detected histopathological subgroup was Burkitt lymphoma. Hyperhydration with or without alkalinisation, and allopurinol were used in first-line treatment and prophylaxis of TLS. Laboratory TLS and clinical TLS was observed in 30.8% and 12.1% of patients, respectively. A significant correlation was found between young age, advanced stage, high LDH level at presentation, and TLS. AKI was observed in 12.1% of the patients. When the glomerular filtration rate values of the patients at the first and last admissions were compared after an average of 6.9 years, a mean decrease of 10 mL/min/1.73 m2 was found. It was not, however, found to be statistically significant.

CONCLUSION

Lower age, advanced stage, and high LDH level at presentation were found to be risk factors for TLS in our study. Long-term renal function loss was not observed in the survivors who received early and careful prophylaxis/treatment for TLS. The survivors are still being followed up.

Fluid Balance and Its Association With Mortality and Health-Related Quality of Life: A Nonprespecified Secondary Analysis of the Life After Pediatric Sepsis Evaluation

OBJECTIVES

To evaluate the association between fluid balance (FB) and health-related quality of life (HRQL) among children at 1 month following community-acquired septic shock.

DESIGN

Nonprespecified secondary analysis of the Life After Pediatric Sepsis Evaluation. FB was defined as 100 × [(cumulative PICU fluid input - cumulative PICU fluid output)/PICU admission weight]. Three subgroups were identified: low FB (< 5%), medium FB (5%-15%), and high FB (> 15%) based on cumulative FB on days 0-3 of ICU stay. HRQL was measured at ICU admission and 1 month after using Pediatric Quality of Life Inventory 4.0 Generic Core or Infant Scales or the Stein-Jessop Functional Status Scale. The primary outcome was a composite of mortality or greater than 25% decline in HRQL 1 month after admission compared with baseline.

SETTING

Twelve academic PICUs in the United States.

PATIENTS

Critically ill children between 1 month and 18 years, with community-acquired septic shock who survived to at least day 4.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Two hundred ninety-three patients were included of whom 66 (23%) had low FB, 127 (43%) had medium FB, and 100 (34%) had high FB. There was no difference in Pediatric Risk of Mortality Score 3 (median 11 [6, 17]), age (median 5 [1, 12]), or gender (47% female) between FB groups. After adjusting for potential confounders and comparing with medium FB, higher odds of mortality or greater than 25% HRQL decline were seen in both the low FB (odds ratio [OR] 2.79 [1.20, 6.57]) and the high FB (OR 2.16 [1.06, 4.47]), p = 0.027. Compared with medium FB, low FB (OR 4.3 [1.62, 11.84]) and high FB (OR 3.29 [1.42, 8.00]) had higher odds of greater than 25% HRQL decline.

CONCLUSIONS

Over half of the children who survived septic shock had low or high FB, which was associated with a significant decline in HRQL scores. Prospective studies are needed to determine if optimization of FB can improve HRQL outcomes.

A novel acute kidney injury scoring system for renal and clinical outcomes in pediatric heart transplant patients

BACKGROUND

The development of acute kidney injury (AKI) has been associated with worse outcomes in children after heart transplantation. Our study compares the application of a cumulative six-point Kidney Diseases Improving Global Outcomes (KDIGO) AKI scoring system, utilizing both creatinine and urine output criteria that we term as the AKI-6 criteria, to traditional AKI staging as a predictor for clinical and renal outcomes in the pediatric heart transplant recipients.

METHODS

We conducted a retrospective single-center chart review on 155 pediatric patients who underwent heart transplantation from May 2014 to December 2021. The primary independent variable was the presence of severe AKI. Severe AKI by KDIGO was defined as Stage ≥2, whereas severe AKI by AKI-6 was defined as cumulative scores ≥4 or Stage 3 AKI based on either KDIGO criterion alone. Primary outcomes included actuarial survival and renal dysfunction by 1-year post-transplant, defined as an estimated glomerular filtration rate <60 mL/min/1.73 m2 .

RESULTS

In total, 140 (90%) patients developed AKI; 98 (63%) patients developed severe AKI by KDIGO, and 60 (39%) by AKI-6. Severe AKI by AKI-6 was associated with worse actuarial survival following heart transplantation compared with KDIGO (p = 0.01). Of the 143 patients with 1-year creatinine data, 6 (11%) patients out of 54 with severe AKI by AKI-6 had evidence of renal dysfunction (p = 0.01), compared with 6 (7%) patients out of 88 by KDIGO (p = 0.3).

CONCLUSIONS

AKI-6 scoring provides greater prognostic utility for actuarial survival and renal dysfunction by 1-year post-heart transplantation in pediatric patients than traditional KDIGO staging.

Perspectives of Pediatric Nephrologists, Intensivists and Nurses Regarding AKI Management and Expected Outcomes

Background

Acute kidney injury (AKI) in critically ill children is associated with increased risk for short- and long-term adverse outcomes. Currently, there is no systematic follow-up for children who develop AKI in intensive care unit (ICU).

Objective

This study aimed to assess variation regarding management, perceived importance, and follow-up of AKI in the ICU setting within and between healthcare professional (HCP) groups.

Design

Anonymous, cross-sectional, web-based surveys were administered nationally to Canadian pediatric nephrologists, pediatric intensive care unit (PICU) physicians, and PICU nurses, via professional listservs.

Setting

All Canadian pediatric nephrologists, PICU physicians, and nurses treating children in the ICU were eligible for the survey.

Patients

N/A.

Measurements

Surveys included multiple choice and Likert scale questions on current practice related to AKI management and long-term follow-up, including institutional and personal practice approaches, and perceived importance of AKI severity with different outcomes.

Methods

Descriptive statistics were performed. Categorical responses were compared using Chi-square or Fisher's exact tests; Likert scale results were compared using Mann-Whitney and Kruskal-Wallis tests.

Results

Surveys were completed by 34/64 (53%) pediatric nephrologists, 46/113 (41%) PICU physicians, and 82 PICU nurses (response rate unknown). Over 65% of providers reported hemodialysis to be prescribed by nephrology; a mix of nephrology, ICU, or a shared nephrology-ICU model was reported responsible for peritoneal dialysis and continuous renal replacement therapy (CRRT). Severe hyperkalemia was the most important renal replacement therapy (RRT) indication for both nephrologists and PICU physicians (Likert scale from 0 [not important] to 10 [most important]; median = 10, 10, respectively). Nephrologists reported a lower threshold of AKI for increased mortality risk; 38% believed stage 2 AKI was the minimum compared to 17% of PICU physicians and 14% of nurses. Nephrologists were more likely than PICU physicians and nurses to recommend long-term follow-up for patients who develop any AKI during ICU stay (Likert scale from 0 [none] to 10 [all patients]; mean=6.0, 3.8, 3.7, respectively) (P < .05).

Limitations

Responses from all eligible HCPs in the country could not obtained. There may be differences in opinions between HCPs that completed the survey compared to those that did not. Additionally, the cross-sectional design of our study may not adequately reflect changes in guidelines and knowledge since survey completion, although no specific guidelines have been released in Canada since survey dissemination.

Conclusions

Canadian HCP groups have variable perspectives on pediatric AKI management and follow-up. Understanding practice patterns and perspectives will help optimize pediatric AKI follow-up guideline implementation.

Clinical and Laboratory Characteristics of Hemophagocytic Lymphohistiocytosis in Children With Severe Dengue During the 2019-2020 Outbreak in Southern Colombia

BACKGROUND

Hemophagocytic lymphohistiocytosis (HLH) is characterized by uncontrolled activation of inflammatory cells and an exaggerated release of cytokines. It can be triggered by different factors, including viruses, such as dengue. The objective of this study was to characterize the clinical and laboratory profiles of children with severe dengue and HLH, and to identify the risk factors for this clinical complication.

METHODS

An analytical study was conducted in children with severe dengue who were treated in an intensive care unit between January 2019 and March 2020. Clinical and laboratory factors were compared between patients with and without HLH.

RESULTS

HLH represented 13.4% (15/112) of children with severe dengue. Patients with HLH had a long-lasting fever (10.1 vs. 5.8 days; P = 0.012), low hemoglobin levels (7.6 vs. 10.8 g/dL; P = 0.000) and high aspartate aminotransferase values (4443 vs. 1061 U/L; P = 0.002), alanine transaminase (1433 vs. 487 U/L; P = 0.004), partial thromboplastin time (80.6 vs. 51.8 seconds; P = 0.010), prothrombin time (23.5 vs. 19.6 seconds; P = 0.024), triglycerides (333.7 vs. 223.2 mg/dL; P = 0.005), lactate dehydrogenase (4209 vs. 1947 U/L; P = 0.006), soluble CD25 (3488 vs. 1026 pg/mL; P = 0.014), and presented with higher frequency of myocarditis (66.7% vs. 38.3%; P = 0.048), hepatitis (5.3% vs. 1.3%; P = 0.014), bacterial coinfection (73.3% vs. 26.7%; P = 0.010) and fatal outcome (26% vs. 5%; P = 0.037).

CONCLUSIONS

HLH is a serious life-threatening clinical complication of dengue virus infection that must be considered, particularly during outbreaks.

Paediatric rhabdomyolysis: A UK centre's 10-year retrospective experience

AIMS

To describe the aetiologies of paediatric rhabdomyolysis and explore the medium-term renal consequences.

METHODS

Retrospective, single-centre review of children with rhabdomyolysis.

RESULTS

Two hundred and thirty-two children met inclusion criteria for the analysis. Mean age at presentation was 8.4 (SD ± 5.5) years. The commonest aetiology was infection (28%), with viral myositis making up the clear majority (75%). Trauma was identified as a cause in 18% of children, seizures in 10% and immune-mediated mechanisms in 8%. Acute kidney injury (AKI) was present in 32% of the cases overall. Children with AKI tended to be younger, with higher peak creatine kinase (CK) and active urinary sediment on urinalysis at presentation. AKI and the need for renal replacement therapy (RRT) were associated with a prolonged hospital stay (15 (interquartile range, IQR 6.5-33) vs. 2 (IQR 0-7) days). A total of 18 children and young people required RRT, with a mean duration of 7.1 ± 4.3 days. Those who received RRT were more likely to have abnormalities on urinalysis at presentation (46% vs. 5%). Over the period of the study, 9% of children died and 2% met criteria for a diagnosis of chronic kidney disease.

CONCLUSIONS

This large paediatric rhabdomyolysis case series provides new and unique insights into the condition. Our results highlight the common aetiologies and provide evidence of good renal recovery overall, even in the most severely affected cases. Abnormalities of urinalysis appear to be important in predicting the development of AKI and the need for RRT.

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

INTRODUCTION

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

METHOD

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

RESULTS

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

CONCLUSIONS

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

Use of Aminophylline to Reverse Acute Kidney Injury in Pediatric Critical Care Patients

OBJECTIVE

Acute kidney injury (AKI) is a complication encountered in 18% to 51% of pediatric critical care patients admitted for treatment of other primary diagnoses and is an independent risk factor for increased morbidity and mortality. Aminophylline has shown promise as a medication to treat AKI, but published studies have shown conflicting results. Our study seeks to assess the reversal of AKI following the administration of aminophylline in critically ill pediatric patients.

METHODS

We performed a single-institution retrospective chart review of pediatric inpatients who were diagnosed with AKI and subsequently treated with non-continuous dose aminophylline between January 2016 and December 2018. Data were collected beginning 2 days prior to the initial dose of aminophylline through completion of the 5-day aminophylline course.

RESULTS

Nineteen therapies among 17 patients were included in analysis. Twelve of the therapies resulted in resolution of AKI during the study period. We observed urine output increase of 19% (p = 0.0063) on the day following initiation of aminophylline therapy in the subset of patients whose AKI resolved. Trends toward decreased serum creatinine and lower inotropic support were also noted.

CONCLUSIONS

Based on these findings, aminophylline could be considered a potentially effective medication for use as rescue therapy in critically ill children with AKI. Limitations include small study population and retrospective nature. Further research in this area with a larger study population and a randomized control trial would allow for better characterization of the efficacy of aminophylline in reversal of AKI.

Pediatric Reference Change Value Optimized for Acute Kidney Injury: Multicenter Retrospective Study in China

OBJECTIVES

The standard definition of pediatric acute kidney injury (AKI) is evolving, especially for critically ill in the PICU. We sought to validate the application of the Pediatric Reference Change Value Optimized for Acute Kidney Injury in Children (pROCK) criteria in critically ill children.

DESIGN

Multicenter retrospective study.

SETTING

Six PICUs in mainland China.

PATIENTS

One thousand six hundred seventy-eight hospitalized children admitted to the PICU with at least two creatinine values within 7 days.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

AKI was diagnosed and staged according to the Pediatric Risk, Injury, Failure, Loss, End-Stage Renal Disease (pRIFLE), the Kidney Disease Improving Global Outcomes (KDIGO), and the pROCK criteria. Multiple clinical parameters were assessed and analyzed along with 90-day follow-up outcomes. According to the definitions of pRIFLE, KDIGO, and pROCK, the prevalence of AKI in our cohort of 1,678 cases was 52.8% (886), 39.0% (655), and 19.0% (318), respectively. The presence of AKI, as defined by pROCK, was associated with increased number of injured organs, occurrence of sepsis, use of mechanical ventilation, use of continuous renal replace therapy ( p < 0.05), higher Pediatric Risk of Mortality III score, and higher Pediatric Logistic Organ Dysfunction-2 score ( p < 0.001). The survival curve of 90-day outcomes showed that pROCK was associated with shorter survival time (LogRank p < 0.001), and pROCK definition was associated with better separation of the different stages of AKI from non-AKI ( p < 0.001).

CONCLUSIONS

In this retrospective analysis of AKI criteria in PICU admissions in China, pROCK is better correlated with severity and outcome of AKI. Hence, the pROCK criteria for AKI may have better utility in critically ill children.

Update on Pediatric Acute Kidney Injury

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

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

OBJECTIVES

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

DESIGN

Prospective quality improvement study.

SETTING

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

PATIENTS

All children admitted to PICU.

INTERVENTIONS

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

MEASUREMENT AND MAIN RESULTS

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

CONCLUSIONS

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

The role of neuroimmune and inflammation in pediatric uremia-induced neuropathy

Uremic neuropathy in children encompasses a wide range of central nervous system (CNS), peripheral nervous system (PNS), autonomic nervous system (ANS), and psychological abnormalities, which is associated with progressive renal dysfunction. Clinically, the diagnosis of uremic neuropathy in children is often made retrospectively when symptoms improve after dialysis or transplantation, due to there is no defining signs or laboratory and imaging findings. These neurological disorders consequently result in increased morbidity and mortality among children population, making uremia an urgent public health problem worldwide. In this review, we discuss the epidemiology, potential mechanisms, possible treatments, and the shortcomings of current research of uremic neuropathy in children. Mechanistically, the uremic neuropathy may be caused by retention of uremic solutes, increased oxidative stress, neurotransmitter imbalance, and disturbance of the blood-brain barrier (BBB). Neuroimmune, including the change of inflammatory factors and immune cells, may also play a crucial role in the progression of uremic neuropathy. Different from the invasive treatment of dialysis and kidney transplantation, intervention in neuroimmune and targeted anti-inflammatory therapy may provide a new insight for the treatment of uremia.

Acute kidney injury in pediatrics: an overview focusing on pathophysiology

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

Major adverse kidney events after acute kidney injury in the pediatric intensive care unit: a propensity score-matched cohort study

BACKGROUND

Acute kidney injury (AKI) in patients admitted to the pediatric intensive care unit (PICU) is associated with poor short-term and long-term outcomes. Greater awareness of long-term AKI-associated outcomes is needed to optimally plan follow-up and management after ICU discharge. We used propensity score methods to study associations between pediatric AKI and major adverse kidney outcomes, including mortality.

METHODS

We included all children 6 months-18 years admitted to PICU at Seattle Children's Hospital from 7/1/2009 to 12/31/2018. Our primary outcome measure was Major Adverse Kidney Events at 30 days (MAKE30): creatinine > 200% of baseline, eGFR < 60 mL/min/1.73 m², dialysis dependence, or mortality. Propensity scores for AKI development in PICU were generated using demographic, medical history, admission, and PICU hospitalization variables. Patients with AKI were matched to control patients without AKI. Logistic regression was used to test association between AKI status and MAKE30.

RESULTS

In the unmatched cohort (n = 878), patients with AKI had lower platelet count (160 vs. 222) and higher PRISM III score (11 vs. 3.5). After propensity score matching, those with AKI vs. no AKI had similar PRISM III scores (9 vs. 10) and platelet count (163 vs. 159). AKI was significantly associated with MAKE30 after propensity score matching (OR: 2.97; 95% CI 1.82-4.84).

CONCLUSIONS

Propensity score matching significantly reduced imbalance in baseline characteristics between those with and without AKI. After matching, AKI remained significantly associated with MAKE30. Patients who developed AKI were more likely to have abnormal kidney function at 30 and 90 days after ICU admission and may be at high risk for developing CKD in the future. A higher resolution version of the Graphical abstract is available as Supplementary information.

Dexmedetomidine and acute kidney injury following cardiac surgery in pediatric patients—An updated systematic review and meta-analysis

Background

Acute kidney injury (AKI) is a common postoperative complication in pediatric patients undergoing cardiac surgery and associated with poor outcomes. Dexmedetomidine has the pharmacological features of organ protection in cardiac surgery patients. The aim of this meta-analysis is to investigate the effect of dexmedetomidine infusion on the incidence of AKI after cardiac surgery in pediatric patients.

Methods

The databases of Pubmed, Embase, and Cochrane Library were searched until April 24, 2022 following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. RevMan 5.3 was used to perform statistical analyses.

Results

Five relevant trials with a total of 630 patients were included. The pooled result using fixed-effects model with OR demonstrated significant difference in the incidence of AKI between patients with dexmedetomidine and placebo (OR = 0.49, 95% CI: [0.33, 0.73], I² = 0%, p for effect = 0.0004). Subgroup analyses were performed based on congenital heart disease (CHD) types and dexmedetomidine intervention time. Pooled results did not demonstrate considerable difference in the incidence of AKI in pediatric patients receiving intraoperative (OR = 0.53, 95% CI: [0.29, 0.99], I² = 0%, p for effect = 0.05) or postoperative dexmedetomidine infusion (OR = 0.56, 95% CI: [0.31, 1.04], p for effect = 0.07), but a significant difference in patients receiving combination of intra- and postoperative dexmedetomidine infusion (OR = 0.27, 95% CI: [0.09, 0.77], p for effect = 0.01). Besides, there was no significant difference in duration of mechanical ventilation (SMD: –0.19, 95% CI: –0.46 to 0.08, p for effect = 0.16; SMD: –0.16, 95% CI: –0.37 to 0.06, p for effect = 0.15), length of ICU (SMD: 0.02, 95% CI: –0.41 to 0.44, p for effect = 0.93) and hospital stay (SMD: 0.2, 95% CI: –0.13 to 0.54, p for effect = 0.23), and in-hospital mortality (OR = 1.26, 95% CI: 0.33–4.84, p for effect = 0.73) after surgery according to the pooled results of the secondary outcomes.

Conclusion

Compared to placebo, dexmedetomidine could significantly reduce the postoperative incidence of AKI in pediatric patients undergoing cardiac surgery with cardiopulmonary bypass (CPB), but the considerable difference was reflected in the pediatric patients receiving combination of intra- and postoperative dexmedetomidine infusion. Besides, there was no significant difference in duration of mechanical ventilation, length of ICU and hospital stay, or in-hospital mortality after surgery.

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.

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

Objective

The epidemiology and outcomes of acute kidney disease (AKD) after acute kidney injury (AKI) in hospitalized children are poorly described. The aim of this study is to investigate the prevalence, predictive factors, and clinical outcomes of AKD in hospitalized children with AKI.

Methods

Children (1 month-18 years) with AKI during hospitalization in the Second Xiangya Hospital from January 2015 to December 2020 were identified. AKD was defined based on the consensus report of the Acute Disease Quality Initiative 16 workgroup. The endpoints include adverse outcomes in 30 and 90 days. Multivariable logistic regression analyses were used to estimate the odds ratio of 30- and 90-day adverse outcomes associated with AKD and identify the risk factors of AKD.

Results

AKD was developed in 42.3% (419/990) of the study patients, with 186 in AKD stage 1, 107 in AKD stage 2, and 126 in AKD stage 3. Pediatric patients with AKD stages 2-3 had significantly higher rates of developing 30- and 90-day adverse outcomes than those with AKD stage 0 and 1. The adjusted odds ratio of AKD stage 2-3 was 12.18 (95% confidence interval (CI), 7.38 - 20.09) for 30-day adverse outcomes and decreased to 2.49 (95% CI, 1.26 - 4.91) for 90-day adverse outcomes. AKI stages 2 and 3, as well as glomerulonephritis, were the only predictive factors for AKD stage 2-3.

Conclusion

AKD is frequent among hospitalized pediatric AKI patients. AKD stage 2-3 represents a high-risk subpopulation among pediatric AKI survivors and is independently associated with 30- and 90-day adverse outcomes. Awareness of the potential risks associated with AKD stage 2-3 and its risk factors may help improve outcomes through careful monitoring and timely intervention.

Modified Schwartz formula and 99mTc-DTPA plasma clearance methods to calculate glomerular filtration rate in critically ill children

BACKGROUND

Studies comparing the modified Schwartz formula with measured GFR (m-GFR) are lacking in critically ill children.

METHODS

This prospective cohort study enrolled children aged 1 month to 12 years, within 24 h of admission. m-GFR measured by technetium-99m-labeled diethylenetriaminepentaacetic acid (^99mTc-DTPA) and calculated by Russell's two-sample slope-intercept method. Serum creatinine was estimated by modified Jaffe method and estimated GFR (e-GFR) calculated by modified Schwartz formula. The primary outcome was to find agreement between the two methods. Bias, precision, and accuracy were calculated. Secondary outcomes were the incidence of AKI (by p-RIFLE criteria) and the difference between the two methods to diagnose AKI.

RESULTS

A total of 208 pairs were analyzed. e-GFR showed good agreement with m-GFR with a mean bias of -4.37 ml/min/1.73 m² and precision (SD of bias) of 33.07, 95% limit of agreement -69.18 to 60.45, and intraclass correlation of 74% (95%CI 66-80%, P < 0.001). e-GFR underestimated m-GFR by 19.8% (95% CI 7.9-31.7%). Accuracy of e-GFR values within 10%, 20%, and 30% of m-GFR were 68.3%, 72.6%, and 78.8%, respectively. Incidence of AKI within 24 h was 60.1% by e-GFR and 54.3% by m-GFR (kappa 0.569, P < 0.001; sensitivity of 85.8%, 95%CI (78-91.7%).

CONCLUSIONS

The modified Schwartz formula shows good agreement with ^99mTc-labeled DTPA double plasma sample clearance method for calculating GFR in critically ill children aged 1 month to 12 years. The underestimation of GFR should be kept in mind while applying the formula at the bedside in PICU.

TRIAL REGISTRATION

Protocol accessible at Clinical Trial Registry of India (CTRI) www.ctri.nic.in . (Trial Registered Prospectively and Registration No. CTRI/2017/10/010014) ([Registered on: 06/10/2017] Trial Registered Prospectively.) (Title "Measured glomerular filtration rate using Diethylenetriaminepentaacetic acid (DTPA) renal scan versus estimated glomerular filtration rate using modified Schwartz formula in critically ill children: A prospective observational, analytical study."). A higher resolution version of the Graphical abstract is available as Supplementary information.

Biomarkers of acute kidney injury in pediatric cardiac surgery

Acute kidney injury (AKI) is characterized by a sudden decrease in kidney function. Children with congenital heart disease are a special group at risk of developing AKI. We performed a systematic review of the literature to search for studies reporting the usefulness of novel urine, serum, and plasma biomarkers in the diagnosis and progression of AKI and their association with clinical outcomes in children undergoing pediatric cardiac surgery. In thirty studies, we analyzed the capacity to predict AKI and poor outcomes of five biomarkers: Cystatin C, Neutrophil gelatinase-associated lipocalin, Interleukin-18, Kidney injury molecule-1, and Liver fatty acid-binding protein. In conclusion, we suggest the need for further meta-analyses with the availability of additional studies.

Association of Preoperative Diuretic Use With Early Acute Kidney Injury in Infants With Biventricular Hearts Following Cardiac Surgery

Background Diuretics are used to manage congestive heart failure in infants with congenital heart disease. Adult data indicate that preoperative diuretic use increases the risk of cardiac surgery associated acute kidney injury (CS-AKI). We have sought to understand if preoperative diuretics in infants increases the risk of CS-AKI. Methods and Results This is a single-center retrospective study of infants (1-12 months) who had CS requiring cardiopulmonary bypass between 2013 and 2018. The diagnosis and severity of CS-AKI was defined according to the Kidney Disease Improving Global Outcomes guidelines. Three hundred patients were included (mean 6 months, SD 2.4, range 1.2-12.9 months). A total of 149 (49.7%) patients were diagnosed with CS-AKI (stage 1: 80 [54%], stage 2: 57 [38%], stage 3: 12 [8%]). Logistic regression analysis showed preoperative diuretics were not associated with CS-AKI (odds ratio [OR], 0.79; 95% CI, 0.43-1.44; P=0.45). A diagnosis of tetralogy of Fallot was an independent risk factor for CS-AKI (OR, 3.49; 95% CI, 1.33-9.1, P=0.01). A diagnosis of tetralogy of Fallot (OR, 3.6; 95% CI, 1.28-10.22; P=0.02) and longer cardiopulmonary bypass (OR, 1.01; 95% CI, 1.0-1.02; P=0.04) time are risk factors for moderate to severe CS-AKI. Conclusions Preoperative diuretic use does not contribute to the risk of CS-AKI in infants early after surgery. A diagnosis of tetralogy of Fallot was the only risk factor for CS-AKI identified using multivariate analysis in our cohort. Furthermore, a diagnosis of tetralogy of Fallot and longer cardiopulmonary bypass time are risk factors for moderate to severe CS-AKI.

Modifiable factors affecting renal preservation in type I glycogen storage disease after liver transplantation: a single-center propensity-match cohort study

BACKGROUND AND AIMS

Glycogen storage disease type I (GSD-I) is an autosomal recessive disorder of carbohydrate metabolism, resulting in limited production of glucose and excessive glycogen storage in the liver and kidneys. These patients are characterized by life-threatening hypoglycemia, metabolic derangements, hepatomegaly, chronic kidney disease, and failure to thrive. Liver transplantation (LT) has been performed for poor metabolic control and delayed growth. However, renal outcome was diverse in pediatric GSD patients after LT. The aim of this study was to investigate the long-term outcome of renal function in pediatric GSD-I patients after living donor LT (LDLT), and to identify modifiable variables that potentially permits LT to confer native renal preservation.

METHODS

The study included eight GSD-Ia and one GSD-Ib children with a median age of 9.0 (range 4.2-15.7) years at the time of LT. Using propensity score matching, 20 children with biliary atresia (BA) receiving LT were selected as the control group by matching for age, sex, pre-operative serum creatinine (SCr) and pediatric end-stage liver disease (PELD) score. Renal function was evaluated based on the SCr, estimated glomerular filtration rate (eGFR), microalbuminuria, and morphological changes in the kidneys. Comparability in long-term renal outcome in terms of anatomic and functional parameters will help to identify pre-LT factors of GSD-I that affect renal prognosis.

RESULTS

The clinical and biochemical characteristics of the GSD and BA groups were similar, including immunosuppressive regimens and duration of follow-up (median 15 years) after LT. Overall, renal function, including eGFR and microalbuminuria was comparable in the GSD-I and BA groups (median eGFR: 111 vs. 123 ml/min/1.73m2, P = 0.268; median urine microalbuminuria to creatinine ratio: 16.0 vs. 7.2 mg/g, P = 0.099, respectively) after LT. However, in the subgroups of the GSD cohort, patients starting cornstarch therapy at an older age (≥ 6-year-old) before transplantation demonstrated a worse renal outcome in terms of eGFR change over years (P < 0.001). In addition, the enlarged kidney in GSD-I returned to within normal range after LT.

CONCLUSIONS

Post-LT renal function was well-preserved in most GSD-I patients. Early initiation of cornstarch therapy before preschool age, followed by LT, achieved a good renal prognosis.

Renal tissue desaturation and acute kidney injury in infant cardiac surgery: a prospective propensity score-matched cohort study

BACKGROUND

Previous studies on the association between renal tissue desaturation and acute kidney injury (AKI) in infant cardiac surgery are limited by small sample sizes and inconsistent results. This prospective study aimed to determine the association between renal desaturation and AKI in infants undergoing surgical repair of an isolated ventricular septal defect (VSD).

METHODS

Infants undergoing VSD repair involving cardiopulmonary bypass participated in this prospective cohort study. The exposure of interest was renal tissue desaturation, defined as at least 20% decrease in saturation from baseline for at least 60 consecutive seconds. Intraoperative care was not guided by renal oxygenation, as the anaesthesiologists were blinded to the monitor. The outcome was AKI arising within postoperative Days 1-3. The primary analysis was based on propensity score-matched infants with and without intraoperative renal desaturation.

RESULTS

Intraoperative renal desaturation was detected in 38 of 242 infants using near-infrared spectroscopy. This group of infants was matched with 114 infants without intraoperative renal saturation after propensity score matching. Acute kidney injury occurred in 47% (18/38) and 27% (31/114) of infants with or without renal desaturation, respectively. Infants with renal desaturation had higher odds of developing AKI than infants without renal desaturation based on conditional logistic regression (odds ratio 2.79; 95% confidence interval: 1.21-6.44; P=0.016). The cumulative time of renal desaturation correlated moderately with the ratio of postoperative peak creatinine to preoperative baseline creatinine (r=0.51; P<0.001).

CONCLUSIONS

Intraoperative renal desaturation is associated with increased odds of developing AKI after surgical repair of an isolated VSD involving cardiopulmonary bypass in infants.

CLINICAL TRIAL REGISTRATION

NCT03941015.

Acute Kidney Injury in Pediatric Diabetic Ketoacidosis

OBJECTIVE

To assess the incidence and clinical characteristics of acute kidney injury (AKI) and identify the associated risk factors for AKI in children with type 1 diabetes mellitus (T1DM) and diabetic ketoacidosis (DKA).

METHODS

This was a retrospective study performed over 15 y in a single Korean center. Children aged ≤18-y-old with T1DM and DKA were enrolled and divided into 2 groups according to the presence of AKI.

RESULTS

This study included 90 episodes of DKA in 58 children with T1DM. AKI occurred in a total of 70 hospitalizations (77.8%) of 44 children: 18 (20.0%) with stage 1 AKI, 39 (43.3%) with stage 2 AKI, and 13 (14.4%) with stage 3 AKI. The number of AKI decreased to 28 (47.4%) and 13 (28.3%) after 12 h and 24 h of admission, respectively. The white blood cell count (P = 0.001) and anion gap levels (P = 0.025) were significantly higher and serum bicarbonate level (P = 0.004) was lower in the AKI group. Logistic regression analysis revealed that a longer duration of TIDM and high anion gap were independent predictors of developing severe AKI in pediatric DKA with T1DM (odds ratio, 1.225, P = 0.013; odds ratio, 1.130, P = 0.038).

CONCLUSIONS

AKI frequently occurred in TIDM children with DKA. Longer duration of TIDM and elevated anion gap are associated with occurrence of severe AKI.

Lower albumin level and longer disease duration are risk factors of acute kidney injury in hospitalized children with nephrotic syndrome

BACKGROUND

Children with nephrotic syndrome (NS) are at an increased risk of acute kidney injury (AKI) and the incidence of AKI in this population is reportedly increasing. This study aimed to investigate the incidence, clinical profiles, and risk factors of AKI in hospitalized children with NS through a nationwide study.

METHODS

This retrospective multicenter study included 14 pediatric nephrology centers in Korea. From 2013 to 2017, a total of 814 patients with idiopathic NS were cared for at participating centers. Among them, 363 patients were hospitalized for NS and investigated in this study.

RESULTS

A total of 363 children with NS were hospitalized 574 times. AKI occurred in 93 admissions (16.2%) of 89 patients: 30 (32.3%) stage 1; 24 (25.8%) stage 2; and 39 (41.9%) stage 3. Multivariate logistic regression analysis showed that longer disease duration, lower albumin level, and methylprednisolone pulse treatment were significantly associated with AKI development in hospitalized children with NS. AKI was associated with a longer hospital stay than non-AKI (median 10 vs. 7 days, P = 0.001). Among 93 admissions, 85 (91.4%) episodes recovered from AKI without complication, whereas 6 (6.5%) progressed to advanced chronic kidney disease (CKD).

CONCLUSIONS

AKI is not uncommon in hospitalized children with NS, and its incidence in this nationwide study was 16.2%. Risk factors for AKI in hospitalized children with NS include longer disease duration, lower albumin level, and methylprednisolone pulse therapy. Pediatric NS patients with these characteristics should be under more strict scrutiny for the occurrence of AKI. Graphical abstract.

Be aware of acute kidney injury in critically ill children with COVID-19

BACKGROUND

Acute kidney injury (AKI) is a common complication of critically ill adult patients with COVID-19. However, currently, no studies investigate kidney impairment in children with COVID-19. We investigated incidence and treatment of AKI in pediatric patients with COVID-19 in Wuhan Children's Hospital during the early stages of the COVID-19 pandemic and discuss possible mechanisms of AKI related to SARS-CoV-2 infection.

METHODS

By extracting data from electronic medical records, we conducted a retrospective observational study of kidney involvement in confirmed pediatric COVID-19 cases in Wuhan Children's Hospital during the coronavirus outbreak, from January 24 to March 20, 2020. Clinical presentations, clinical courses, laboratory findings, and medical interventions are described below.

RESULTS

Among 238 confirmed COVID-19 cases, only three were critically ill and needed intensive care unit (ICU) admission. All three developed AKI, but AKI was not detected in any non-critically ill patients outside the ICU. Two of the three patients with AKI had prodromal gastrointestinal symptoms. Significantly elevated interleukin-6 (IL-6) levels and complement activation were observed in these patients with AKI. The three patients with AKI were treated with plasma exchange (PE) and continuous kidney replacement therapy (CKRT), resulting in one complete recovery, one partial recovery, and one mortality due to critical illness.

CONCLUSIONS

Critically ill children with COVID-19 may develop AKI, especially following prodromal gastrointestinal symptoms. An inflammatory storm and complement-mediated injury may underlie AKI development in children with COVID-19. Our study supports implantation of PE and CKRT in management of critically ill patients with AKI.

Role of Hemoperfusion With CytoSorb Associated With Continuous Kidney Replacement Therapy on Renal Outcome in Critically III Children With Septic Shock

Introduction: Sepsis-associated acute kidney injury (SA-AKI) represents a relevant cause of mortality and morbidity in critically ill children. Since with the "inflammatory theory" the authors have been witnessed an important role of inflammatory mediators in the pathophysiology and in the prognosis of SA-AKI, making the need of adjunctive therapies in association with kidney replacement therapies mandatory. Hemoperfusion with CytoSorb is a safe and well-tolerated therapy in septic shock: the very high surface area of the absorber means it is able to efficiently remove cytokines and other medium size molecules involved in cytokine storm, thus playing a synergistic effect with Continuous Kidney Replacement Therapy (CKRT). Materials and Methods: We retrospectively analyzed data from a cohort of eight critically ill children treated from January 2018 to March 2020 describing the impact of CKRT plus hemoperfusion with CytoSorb on renal outcome in critically ill children with septic shock. Results: We evidenced a significant reduction in interleukin (IL)-6 an IL-10 after hemoperfusion with CytoSorb in our pediatric population. Furthermore, we were able to show a significant improvement of creatinine and blood urea nitrogen (BUN) after blood purification and at pediatric intensive care units (PICU) discharge. We have observed a median of 2.5 CKRT days after stop of hemoperfusion (Q₁ 0.25; Q₃ 18.75). None of our patients required CKRT 30 days after PICU discharge (PICU-D). None of them developed CKD. Conclusion: Hemoperfusion with CytoSorb is a valuable therapeutic option in combination with CKRT in SA-AKI. More studies are warranted to confirm our results and in particular to define the role of this adjuvant therapy as a preemptive strategy to protect renal function in pediatric septic shock.

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.

Cushing syndrome with acute kidney injury due to ureteral stones in a 6-year-old boy

Cushing syndrome (CS) is rare in children. The clinical presentation of CS varies according to extent and duration of glucocorticoid excess, and urolithiasis is a common complication. We report the first case of a patient with CS associated with acute kidney injury (AKI) due to urolithiasis. A 6-year-old boy presented to the Emergency Department with seizure. On physical examination, he had clinical features of CS and high blood pressure. Brain computed tomography (CT) suggested posterior reversible encephalopathy syndrome due to hypertension. On evaluation of hypertension, laboratory tests suggested adrenocortical tumor, but abdominal CT suggested pheochromocytoma. During further evaluation, his condition deteriorated with AKI due to bilateral ureteral stones, for which the patient underwent continuous renal replacement therapy in the intensive care unit. After controlling hypercortisolism with etomidate and performing ureteral stent indwelling, an adrenal mass was resected and histologically confirmed as an adrenocortical adenoma. We review the clinical manifestations, diagnosis, and management of CS associated with urolithiasis and AKI. Early recognition and careful monitoring of urolithiasis in CS patients are important to avoid severe complications of urolithiasis.

A Study of Acute Kidney Injury in a Tertiary Care Pediatric Intensive Care Unit

The objective of this study was to calculate the incidence, severity, and risk factors for acute kidney injury (AKI) in a tertiary care pediatric intensive care unit (PICU). Also, to assess the impact of AKI and its varying severity on mortality and length of hospital and PICU stays. A prospective observational study was performed in children between 1 month and 12 years of age admitted to the PICU between July 1, 2013, and July 31, 2014 (13 months). The change in creatinine clearance was considered to diagnose and stage AKI according to pediatric risk, injury, failure, loss, and end-stage renal disease criteria. The risk factors for AKI and its impact on PICU stay, hospital stay, and mortality were evaluated. Of the total 220 patients enrolled in the study, 161 (73.2%) developed AKI, and 59 cases without AKI served as the "no AKI" (control) group. Majority (57.1%) of children with AKI had Failure grade of AKI, whereas 26.1% had Risk grade and 16.8% had Injury grade of AKI. Infancy ( p  = 0.000), hypovolemia ( p  = 0.005), shock ( p  = 0.008), and sepsis ( p  = 0.022) were found to be significant risk factors for AKI. Mortality, PICU stay, and hospital stay were comparable in children with and without AKI as well as between the various grades of renal injury (i.e., Failure, Risk, and Injury ). An exceedingly high incidence of AKI, especially of the severe Failure grade was observed in critically ill children. Infancy and frequent PICU occurrences such as sepsis, hypovolemia, and shock predisposed to AKI.

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

BACKGROUND

Identifying acute kidney injury (AKI) early can inform medical decisions key to mitigation of injury. An AKI risk stratification tool, the renal angina index (RAI), has proven better than creatinine changes alone at predicting AKI in critically ill children.

OBJECTIVE

To derive and test performance of an "acute" RAI (aRAI) in the Emergency Department (ED) for prediction of inpatient AKI and to evaluate the added yield of urinary AKI biomarkers.

METHODS

Study of pediatric ED patients with sepsis admitted and followed for 72 h. The primary outcome was inpatient AKI defined by a creatinine >1.5× baseline, 24-72 h after admission. Patients were denoted renal angina positive (RA+) for an aRAI score above a population derived cut-off. Test characteristics evaluated predictive performance of the aRAI compared to changes in creatinine and incorporation of 4 urinary biomarkers in the context of renal angina were assessed.

RESULTS

118 eligible subjects were enrolled. Mean age was 7.8 ± 6.4 years, 16% required intensive care admission. In the ED, 27% had a +RAI (22% had a >50% creatinine increase). The aRAI had an AUC of 0.92 (0.86-0.98) for prediction of inpatient AKI. For AKI prediction, RA+ demonstrated a sensitivity of 94% (69-99) and a negative predictive value of 99% (92-100) (versus sensitivity 59% (33-82) and NPV 93% (89-96) for creatinine ≥2× baseline). Biomarker analysis revealed a higher AUC for aRAI alone than any individual biomarker.

CONCLUSIONS

This pilot study finds the aRAI to be a sensitive ED-based tool for ruling out the development of in-hospital AKI.

Acute kidney injury in hospitalized children: consequences and outcomes

Over the past decade, the nephrology and critical care communities have adopted a consensus approach to diagnosing acute kidney injury (AKI) and, as a result, we have seen transformative changes in our understanding of pediatric AKI epidemiology. The data regarding outcomes among neonates and children who develop AKI have become far more robust and AKI has been clearly linked with an increased need for mechanical ventilation, longer inpatient stays, and higher mortality. Though AKI was historically thought to be self-limited, we now know that renal recovery is far from universal, particularly when AKI is severe; the absence of recovery from AKI also carries longitudinal prognostic implications. AKI survivors, especially those without full recovery, are at risk for chronic renal sequelae including proteinuria, hypertension, and chronic kidney disease. This review comprehensively describes AKI-related outcomes across the entire pediatric age spectrum, using the most rigorous studies to identify the independent effects of AKI events.

Nephrotoxin exposure and acute kidney injury in critically ill children undergoing congenital cardiac surgery

BACKGROUND

Though acute kidney injury (AKI) is often multifactorial, investigators are now emphasizing the specific contribution of nephrotoxins. This study examines the epidemiology of nephrotoxin exposure and nephrotoxin-associated AKI among children undergoing congenital heart surgery (CHS).

METHODS

This is a retrospective cohort study of children admitted following CHS between June 1, 2014, and September 30, 2014. Nephrotoxins were defined according to the Nephrotoxic Injury Negated by Just-in-time-Action (NINJA) collaborative; high nephrotoxin exposure was defined as receipt of ≥ 3 nephrotoxins concurrently. AKI was diagnosed according to KDIGO creatinine criteria. Severe AKI was defined as KDIGO stage ≥ 2. Poisson models were used to compute adjusted relative risk (aRR) of high nephrotoxin exposure for AKI.

RESULTS

One hundred fifty-four children (median age 20.4 months, IQR 2.3-59.5) were included. One hundred thirty-one (85.1%) received at least one nephrotoxin; 32 (20.8%) received ≥ 3 nephrotoxins. The most commonly administered medications were ketorolac (n = 74, 48.1%), aspirin (n = 62, 40.3%), ibuprofen (n = 51, 33.1%), vancomycin (n = 39, 25.3%), piperacillin/tazobactam (n = 35, 22.7%), and enalapril (n = 14, 9.1%). AKI occurred more commonly in those exposed to ≥ 3 nephrotoxins (62.5 vs. 50.8%); this was not statistically significant after adjusting for confounders (aRR = 1.2, 95% CI 0.9-1.7). Severe AKI was similar between those with and without high nephrotoxin exposure (21.9 vs. 19.7%, p = 0.78).

CONCLUSIONS

Nephrotoxin use is common following pediatric CHS. While we found no association between high nephrotoxin exposure and AKI, this may be related to the multifactorial nature of AKI in this population. For many common nephrotoxins, less injurious agents exist and nephrotoxin exposure may represent a modifiable risk factor for AKI.

Clinical features of acute kidney injury in patients with Kawasaki disease

Although acute kidney injury (AKI) is a common complication in hospitalized children, AKI has rarely been reported in patients with Kawasaki disease (KD). Herein, we review the clinical trajectories of AKI in patients with KD. A total of 39 patients with KD who developed AKI have been reported in 28 publications as case reports. The causes of AKI include prerenal AKI associated with acute heart failure (AHF), intrinsic AKI caused by tubulointerstitial nephritis (TIN), acute nephritic syndrome (ANS), hemolytic uremic syndrome (HUS), immune complex-mediated nephropathy, rhabdomyolysis, and KD shock syndrome (KDSS). Six of the 39 patients (15.4%) underwent renal replacement therapy. While AHF and multiple organ dysfunction syndrome developed in 41% and 68% of KD patients with AKI, respectively, all patients recovered without any renal sequelae. Although the precise pathogenic mechanism underlying the development of AKI in patients with KD is unknown, several possible mechanisms have been proposed, including T-cell-mediated immunologic abnormalities for TIN, renal and glomerular endothelial injury resulting from vasculitis for HUS, immune complex-mediated kidney injury for immune complex-mediated nephropathy and ASN, and capillary leak and an increased release of cytokines with myocardial dysfunction for KDSS.

A New Criterion for Pediatric AKI Based on the Reference Change Value of Serum Creatinine

BACKGROUND

Current definitions of AKI do not take into account serum creatinine's high variability in children.

METHODS

We analyzed data from 156,075 hospitalized children with at least two creatinine tests within 30 days. We estimated reference change value (RCV) of creatinine on the basis of age and initial creatinine level in children without kidney disease or known AKI risk, and we used these data to develop a model for detecting pediatric AKI on the basis of RCV of creatinine. We defined pediatric AKI according to pediatric reference change value optimized for AKI in children (pROCK) as creatinine increase beyond RCV of creatinine, which was estimated as the greater of 20 μmol/L or 30% of the initial creatinine level.

RESULTS

Of 102,817 children with at least two serum creatinine tests within 7 days, 5432 (5.3%) had AKI as defined by pROCK compared with 15,647 (15.2%) and 10,446 (10.2%) as defined by pediatric RIFLE (pRIFLE) and Kidney Disease Improving Global Outcomes (KDIGO), respectively. Children with pROCK-defined AKI had significantly increased risk of death (hazard ratio, 3.56; 95% confidence interval, 3.15 to 4.04) compared with those without AKI. About 66% of patients with pRIFLE-defined AKI and 51% of patients with KDIGO-defined AKI, mostly children with initial creatinine level of <30 μmol/L, were reclassified as non-AKI by pROCK, and mortality risk in these children was comparable with risk in those without AKI by all definitions.

CONCLUSIONS

pROCK criterion improves detection of "true" AKI in children compared with earlier definitions that may lead to pediatric AKI overdiagnosis.

Factors that influenced undergoing renal replacement therapy and survival in children with acute kidney injury

AIM

Acute kidney injury (AKI) is an important clinical condition that is associated with increased mortality and morbidity. This study was performed to identify the factors that influence AKI stage, undergoing renal replacement therapy (RRT) and mortality.

METHODS

This study was retrospectively conducted on 219 children with AKI who had been referred to the paediatric nephrology division of Dr Sami Ulus Teaching Hospital during their inpatient treatment from 2008 to 2012. AKI was defined using pRIFLE criteria.

RESULTS

From the 219 enrolled patients, 131 were identified as having AKI at the time of hospital admission. Infant age group was the largest group. RRT was performed in 68 patients. Median RRT initiation time was 1.5 day (0-2) and the mortality increased significantly when RRT initiation time was >1 day. The likelihood of undergoing RRT was higher for patients who were younger, who were managed in PICU and who had intrinsic type of AKI. pRIFLE stage and AKI place did not influence the likelihood of undergoing RRT. Overall mortality was 26.9%. In log-rank tests, factors influencing survival were younger age, being treated in PICU, developing AKI during inpatient treatment, having a comorbid condition and undergoing RRT. pRIFLE stage did not influence survival. In the logistic regression model, factors associated with mortality included younger age, undergoing RRT and having AKI during inpatient treatment. Having underlying disease and being managed in PICU did not influence the likelihood of death.

CONCLUSION

Acute kidney injury is an important condition in all hospitalized patients. More studies and interventions are needed on this topic to identify, treat and prevent AKI.

Acute Kidney Injury in Nephrotic Syndrome

Nephrotic syndrome (NS) is one of the commonest kidney diseases seen in childhood and is characterized by a relapsing remitting course. Various complications have been reported in children with NS, including infections, thromboembolism, hypovolemia, and acute kidney injury (AKI). There is often a modest decrease in renal function in patients with active proteinuria due to decreased glomerular permeability that improves when they go into remission. However, more pronounced AKI in NS is multifactorial in origin. It is most often secondary to hypovolemia, nephrotoxic medications, and infections, although other reasons may also be seen. Recent years have seen an increase in the incidence of AKI in NS. There is limited data on the correlation between AKI in pediatric NS and long-term outcomes. A better understanding of this increasingly common condition will help improve patient outcomes.