Acute kidney disease predicts chronic kidney disease in pediatric non-kidney solid organ transplant patients

Growth after pediatric and neonatal acute kidney injury: a meta-analysis

BACKGROUND

Acute kidney injury (AKI) occurs commonly in critically ill children. The impact of AKI on pediatric growth outcomes has been sparsely described.

OBJECTIVE

To compare growth in children with a history of AKI compared to those without AKI. We hypothesized that children with AKI would have worse growth compared to those without AKI.

DATA SOURCES

A convenience sample of existing prospective and retrospective cohorts of children with AKI who had already collected or were able to collect data on growth parameters before and after an episode of AKI.

STUDY ELIGIBILITY CRITERIA

There are < 5 studies in the published literature on growth in children with AKI. These investigators were contacted, and additional studies were added by contacting primary investigators of studies of childhood AKI in which data on growth parameters was able to be collected.

PARTICIPANTS AND INTERVENTIONS

Children from existing cohorts evaluating AKI (exposure) during childhood. Each included cohort had previously received local IRB approval per institutional guidelines. As our study was a meta-analysis and only used cohort-level data, no IRB approval was required for this report.

STUDY APPRAISAL AND SYNTHESIS METHODS

Growth parameters (length and weight z-scores) before and after an episode of AKI were compared using a meta-means analysis. MOOSE guidelines were used. Data were pooled using a random-effects model. Hedges g was calculated, and Higgins I2 statistic was used to define variability due to between-cohort heterogeneity.

RESULTS

We included 3,586 children from 17 existing cohorts of AKI in various populations, including infants, children with cardiac disease, solid organ transplant and critically ill children without cardiac disease with follow-up from 12 months to 11 years after AKI. At most distant follow-up, those with AKI had lower length z-score than those without AKI (mean difference -0.37 [95%CI -0.52, -0.22, p < 0.001]) and lower weight z-score (mean difference of -0.29 [95%CI -0.43, -0.15, p < 0.001]). This difference was most striking in infants, as those with AKI had impaired growth (both length z-score and weight z-score) after AKI compared to those without AKI.

LIMITATIONS

The analysis included only a convenience sample of observational cohorts of children, study selection could have been biased, and we did not evaluate the relationship between decreased kidney function (e.g., chronic kidney disease) after AKI in these cohorts and its relationship to poor growth.

CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS

This meta-analysis found that children with AKI have impaired growth after AKI. These findings were most striking in infants. We suggest focusing on growth outcomes in both clinical care and research investigating the impacts of AKI.

SYSTEMATIC REVIEW REGISTRATION NUMBER

NA.

The Incidence and Outcomes of Acute Kidney Disease in Critically Ill Children

Key Points

Major adverse kidney events are common in children who develop acute kidney disease in the intensive care unit. Acute kidney disease criteria identify critically ill children at risk for major adverse kidney event who do not meet AKI or CKD criteria.

Background

Acute kidney disease (AKD) includes abnormalities of kidney function present for <90 days. AKI is defined as a subset of AKD with onset within 7 days. There are scant data on the rates of AKD in children and its association with outcomes. Our primary objective was to examine the rates of AKD with and without AKI and compare major adverse events in children in the pediatric intensive care unit (PICU).

Methods

This is a retrospective cohort study of patients aged 18 years or younger who were admitted to a quaternary care PICU between 2009 and 2016 using the high-density pediatric database. All patients included in the primary analysis had a known baseline serum creatinine. Patients who had a baseline eGFR <60 ml/min per 1.73 m2 or a history of dialysis dependence or kidney transplant were excluded. AKI and AKD were defined by Kidney Disease Improving Global Outcomes definitions. Major adverse kidney events at 90 days (MAKE-90) was defined as a composite outcome of death, dialysis, or persistent kidney dysfunction 90 days after PICU admission.

Results

Among 5922 children included in this study, 1199 (20.2%) had AKD, of which 1092 (91%) had AKD with AKI and 107 (8.9%) had AKD without AKI. MAKE-90 occurred in 26% (308/1199) of those with AKD compared with 3.6% (172/4723) without (P ≤ 0.001). MAKE-90 occurred in 26% (279/1092) of AKD with AKI and 27% (29/107) of AKD without AKI. After adjusting for age, sex, and illness severity, compared with patients who had no AKD, patients with AKD with AKI (adjusted odds ratio, 14.39; 95% confidence interval, 11.06 to 18.72), and patients with AKD without AKI (adjusted odds ratio, 7.83; 95% confidence interval, 4.54 to 13.51) had a greater odds of MAKE-90.

Conclusions

More than a quarter of pediatric critically ill patients with AKD develop MAKE-90. Even in the absence of AKI, AKD is an independent risk factor for MAKE-90.

Pediatric Considerations in Post Acute Kidney Injury Care

Acute kidney injury in children is associated with adverse outcomes. These include longer hospital stays, increased mortality, and nonrecovery of kidney function in the short term and increased health care utilization, new onset hypertension, and chronic kidney disease in the long term. Systematic post acute kidney injury care may help mitigate some of the complications that follow acute kidney injury. Patient, family, and health care team education is a key aspect of post acute kidney injury care. This includes individualized education to the patient and family, ideally prior to hospital discharge, provision of a discharge summary with details of the acute kidney injury episode and follow-up plan, and communication with the primary care provider. Given that severe acute kidney injury may often be seen in patients with other underlying medical conditions, partnership between the primary care provider, non-nephrology specialist and the nephrologist, and the use of telehealth may facilitate follow-up without increasing caregiver burden. Ongoing surveillance includes monitoring kidney function, proteinuria, and hypertension. There are no guidelines on the frequency of this evaluation or the duration of follow-up. These decisions should be individualized based on the characteristics of the index acute kidney injury episode and underlying risk factors for chronic kidney disease.

An innocent bystander or a predisposing culprit? Kidney injury following pediatric liver transplantation

BACKGROUND

Survival after pediatric liver transplantation has increased dramatically over the years, revealing extra-hepatic complications including impaired kidney function. We conducted a large single-center retrospective study to evaluate kidney outcomes after pediatric liver transplantation.

METHODS

From electronic charts of 121 children who underwent liver transplantation during 2007-2020, we collected pre- and post-transplant data. We investigated the presence of post-transplant permanent kidney injury, including proteinuria, hypertension, and decreased estimated glomerular filtration rate (eGFR). We excluded children who died, underwent liver-kidney transplantation, or had less than 1 year of follow-up.

RESULTS

During a median follow-up of 5.1 (interquartile range 2.9-7.3) years, eGFR decreased, mostly in the first year post-transplant. In addition, 41% of the children presented with acute kidney injury. At their last follow-up, 35% showed permanent kidney injury (hypertension 13%, proteinuria 36%, and eGFR < 90 mL/min per 1.73 m2 7%). Kidney ultrasounds were abnormal for 44% of the children at the last visit, compared to 11% before transplant (p < 0.001). In multivariate analysis, abnormal kidney ultrasound before transplant (odds ratio = 4.53, 95% CI 1.1-18.7) and liver disease with potential risk of primary kidney involvement (odds ratio = 4.77, 95% CI 1.58-14.4) were predictors for hypertension or decreased eGFR at the last follow-up.

CONCLUSIONS

The high prevalence of kidney injury after pediatric liver transplantation and the pretransplant predictors for kidney injury highlight the importance of a thorough kidney pretransplant evaluation and follow-up.

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.

Risk Factors and Outcomes Associated With the Development of Persistent Acute Kidney Injury in Non-Renal Solid Organ Transplant Recipients: Systematic Review and Meta-Analysis

Persistent acute kidney injury (pAKI), compared with acute kidney injury (AKI) that resolves in <72 h, is associated with worse prognosis in critically ill patients. Definitions and prognosis of pAKI are not well characterized in solid organ transplant patients. Our aims were to investigate (a) definitions and incidence of pAKI; (b) association with clinical outcomes; and (c) risk factors for pAKI among heart, lung, and liver transplant recipients. We systematically reviewed the literature including PubMed, Embase, Web of Science, and Cochrane from inception to 8/1/2023 for human prospective and retrospective studies reporting on the development of pAKI in heart, lung, or liver transplant recipients. We assessed heterogeneity using Cochran's Q and I2. We identified 25 studies including 6330 patients. AKI (8%-71.6%) and pAKI (2.7%-55.1%) varied widely. Definitions of pAKI included 48-72 h (six studies), 7 days (three studies), 14 days (four studies), or more (12 studies). Risk factors included age, body mass index (BMI), diabetes, preoperative chronic kidney disease (CKD), intraoperative vasopressor use, and intraoperative circulatory support. pAKI was associated with new onset of CKD (odds ratio [OR] 1.41-11.2), graft dysfunction (OR 1.81-8.51), and long-term mortality (OR 3.01-13.96), although significant heterogeneity limited certainty of CKD and graft dysfunction outcome analyses. pAKI is common and is associated with worse mortality among liver and lung transplant recipients. Standardization of the nomenclature of AKI will be important in future studies (PROSPERO CRD42022371952).

Acute Kidney Injury Requiring Dialysis After Pediatric Heart Transplant

BACKGROUND

Acute kidney injury (AKI) is a common complication of pediatric heart transplant, with a subset of patients developing severe AKI requiring dialysis (AKI-D). We aimed to identify the epidemiology, risk factors, and outcomes of postoperative AKI-D in pediatric heart transplant recipients.

METHODS

We retrospectively identified all pediatric first-time, single-organ heart transplants at our institution from 2014 to 2022. Postoperative AKI was defined as AKI within 2 weeks of transplant. Unadjusted and adjusted logistic regression were used to identify characteristics associated with AKI-D, and unadjusted time-to-event analyses were used to determine the association between AKI-D and survival free of kidney failure.

RESULTS

Among 177 patients included, 116 (66%) developed postoperative AKI of any stage, including 13 (7%) who developed AKI-D with median time from transplant to dialysis initiation of 6 days (IQR 3-13). In adjusted models, increased cardiopulmonary bypass time (OR 1.19, 95% CI 1.04-1.37, per 15 min increase in bypass time) and higher weight at transplant were associated with higher odds of AKI-D, whereas patient demographics and pretransplant kidney function were not associated with AKI-D. AKI-D was associated with greater mortality during initial hospitalization (46% vs. 1%, p < 0.001) and a lower rate of survival free of kidney failure.

CONCLUSIONS

The incidence of AKI-D after pediatric heart transplant was 7%, with extended cardiopulmonary bypass time associated with postoperative AKI-D even in adjusted models. Further research is needed to improve the prediction and management of AKI-D in this population.

Immunosuppressants against acute kidney injury: what to prefer or to avoid?

BACKGROUND

Acute kidney injury (AKI) is a critical global health issue associated with high mortality rates, particularly in patients undergoing renal transplants and major surgeries. These individuals often receive immunosuppressants to dampen immune responses, but the impact of these drugs on AKI remains unclear.

OBJECTIVE

This review aims to provide a detailed understanding of the effects of different classes of immunosuppressants against AKI, elucidating their role in either exacerbating or mitigating the occurrence or progression of AKI.

METHODS

Several preclinical and clinical reports were analyzed to evaluate the impact of various immunosuppressants on AKI. Relevant preclinical and clinical studies were reviewed through different databases such as Scopus, PubMed, Google Scholar, and ScienceDirect, and official websites like https://clinicaltrials.gov to understand the mechanisms underlying the effects of immunosuppressants on kidney function.

RESULTS AND DISCUSSION

Specific immunosuppressants have been linked to the progression of AKI, while others demonstrate renoprotective effects. However, there is no consensus on the preferred or avoided immunosuppressants for AKI patients. This review outlines the classes of immunosuppressants commonly used and their impact on AKI, providing guidance for physicians in selecting appropriate drugs to prevent or ameliorate AKI.

CONCLUSION

Understanding the effects of immunosuppressants on AKI is crucial for optimizing patient care. This review highlights the need for further research to determine the most suitable immunosuppressants for AKI patients, considering both their efficacy and potential side effects.

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.

A reappraisal of risk factors for hypertension after pediatric acute kidney injury

BACKGROUND

Acute kidney injury (AKI) is common in hospitalized children and increases the risk of chronic kidney disease (CKD) and hypertension, but little is known about the patient level risk factors for pediatric hypertension after AKI. The aims of this study are to evaluate the prevalence and risk factors for new onset hypertension in hospitalized children with AKI and to better understand the role of acute kidney disease (AKD) in the development of hypertension.

METHODS

This study was an observational cohort of all children ≤ 18 years old admitted to a single tertiary care children's hospital from 2015 to 2019 with a diagnosis of AKI. Hypertension was defined as blood pressure > 95th percentile for sex, age, height, diagnosis of hypertension on the problem list, or prescription of antihypertensive medication for > 90 days after AKI.

RESULTS

A total of 410 children were included in the cohort. Of these, 78 (19%) developed hypertension > 90 days after AKI. A multivariable logistic regression model identified AKD, need for kidney replacement therapy, congenital heart disease, and non-kidney solid organ transplantation as risk factors for hypertension after AKI.

CONCLUSIONS

Incident hypertension after 3 months is common among hospitalized children with AKI, and AKD, need for dialysis, congenital heart disease, and non-kidney solid organ transplant are significant risk factors for hypertension after AKI. Monitoring for hypertension development in these high-risk children is critical to mitigate long-term adverse kidney and cardiovascular outcomes.

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.

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.

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.