Pediatric Acute Kidney Injury-The Time for Nihilism Is Over

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.

Chronic kidney disease in children: an update

Chronic kidney disease (CKD) is a major healthcare issue worldwide. However, the prevalence of pediatric CKD has never been systematically assessed and consistent information is lacking in this population. The current definition of CKD is based on glomerular filtration rate (GFR) and the extent of albuminuria. Given the physiological age-related modification of GFR in the first years of life, the definition of CKD is challenging per se in the pediatric population, resulting in high risk of underdiagnosis in this population, treatment delays and untailored clinical management. The advent and spreading of massive-parallel sequencing technology has prompted a profound revision of the epidemiology and the causes of CKD in children, supporting the hypothesis that CKD is much more frequent than currently reported in children and adolescents. This acquired knowledge will eventually converge in the identification of the molecular pathways and cellular response to damage, with new specific therapeutic targets to control disease progression and clinical features of children with CKD. In this review, we will focus on recent innovations in the field of pediatric CKD and in particular those where advances in knowledge have become available in the last years, with the aim of providing a new perspective on CKD in children and adolescents.

Neonatal Acute Kidney Injury: Understanding of the Impact on the Smallest Patients

The study of neonatal acute kidney injury (AKI) has transitioned from small, single-center studies to the development of a large, multicenter cohort. The scope of research has expanded from assessment of incidence and mortality to analysis of more specific risk factors, novel urinary biomarkers, interplay between AKI and other organ systems, impact of fluid overload, and quality improvement efforts. The intensification has occurred through collaboration between the neonatology and nephrology communities. This review discusses 2 case scenarios to illustrate the clinical presentation of neonatal AKI, important risk factors, and approaches to minimize AKI events and adverse long-term 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.

Acute Kidney Injury Following Pediatric Liver Transplant

OBJECTIVE

To determine the incidence, severity, and risk factors of postoperative acute kidney injury in pediatric liver transplant patients with and without inborn errors of metabolism.

DESIGN

Retrospective cohort study.

SETTING

Single-center PICU.

PATIENTS

All children less than or equal to 18 years old who received a liver transplant between January 2009 and July 2019.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Following exclusion criteria there were 92 transplant encounters. After excluding patients who received combined kidney-liver transplantation, acute kidney injury occurred in 57% of patients (N = 49), with 25.6% (N = 22) stage 1, 15.1% (N = 13) stage 2, and 16.3% (N = 14) stage 3. In an adjusted analysis, metabolic indication for transplant was not significantly associated with presence of acute kidney injury (p = 0.45). For the subset of patients without inborn errors of metabolism, the odds of having acute kidney injury was 1.50 (95% CI: 1.00-2.26) for each 1-unit increase in preoperative INR after adjusting for the covariates of age, preoperative albumin, CMV status of donor, and preoperative creatinine. In the full cohort, as well as the sample of children without inborn errors of metabolism, presence of acute kidney injury was associated with longer total hospital stay as well as number of ICU days.

CONCLUSIONS

Acute kidney injury in the early postoperative period is common in pediatric liver transplant patients (57%), 31.4% of whom had severe disease. In patients without inborn errors of metabolism, each unit increase in preoperative INR suggests a higher risk of acute kidney injury after adjusting for covariates including preoperative creatinine. This finding suggests an association between the severity of preoperative synthetic liver function and the risk of developing postoperative acute kidney injury which requires further investigation.

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.