Clinical phenotypes of acute kidney injury are associated with unique outcomes in critically ill septic children

Renal resistive index by point of care ultrasound to predict sepsis associated acute kidney injury in critically ill children

BACKGROUND

Sepsis associated acute kidney injury (AKI) is linked with adverse outcomes in the PICU. Doppler-based renal resistive index (RRI) has shown promising results in adults for prediction of AKI. We aimed to explore the performance of RRI in children with sepsis.

METHODS

This prospective observational study (March - November 2022) included children aged 1-12 years with sepsis admitted to the PICU. RRI and urine neutrophil gelatinase associated lipocalin (NGAL) were measured within 12 h of admission. Children were followed up for 3 days. AKI (new and persistent) was defined as any child with KDIGO stage 2 or 3 AKI on day 3.

RESULTS

We enrolled 90 children but included 79 in final analysis. Two thirds (n = 53, 67%) had septic shock. Median (IQR) age was 6.2 years (4.1-9.2). RRI decreased with increasing age. Twenty-six (33%) children had AKI on day 3. Mean (SD) RRI was higher in the AKI group [0.72 (0.08) vs. 0.65 (0.07), p < 0.001].The area under ROC curve for RRI to detect AKI among the 1-4 year old group was 0.75 (95% CI:0.51, 0.98; p = 0.05) and among the 5-12 year old group was 0.76 (0.62, 0.89; p = 0.001). An RRI 0.71 predicted AKI with 100% sensitivity and 46.2% specificity among the 1-4-year-old group and RRI 0.69 predicted it with 70% sensitivity and 77.5% specificity in the 5-12-year-old group. RRI and eGFR at admission were independent predictors of AKI on multivariable analysis. Urine NGAL 94.8 ng/ml predicted AKI with 76.9% sensitivity and 77.4% specificity and AUROC was 0.74 (0.62, 0.86) among the 1-12-year-old group.

CONCLUSIONS

RRI values varied with age. RRI showed good diagnostic accuracy to detect new/persistent AKI on day 3 in children with sepsis; however, it was less precise as an independent predictor.

Characteristics and Risk Factors for Pediatric Sepsis

OBJECTIVE

Sepsis is considered a major cause of health loss in children and had high mortality and morbidity. Currently, there is no reliable model for predicting the prognosis of pediatric patients with sepsis. This study aimed to analyze the clinical characteristics of sepsis in children and assess the risk factors associated with poor prognosis in pediatric sepsis patients to identify timely interventions and improve their outcomes.

METHODS

This study analyzed the clinical indicators and laboratory results of septic patients hospitalized in the Pediatric Intensive Care Unit of Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, China, from January 1, 2019, to December 31, 2021. Risk factors for sepsis were identified by logistic regression analyses.

RESULTS

A total of 355 children with sepsis were enrolled, with 333 children (93.8%) in the good prognosis group, and 22 children (6.2%) in the poor prognosis group. Among them, there were 255 patients (71.8%) in the sepsis group, and 100 patients (28.2%) in the severe sepsis group. The length of hospital stay in the poor prognosis group was longer than that in the good prognosis group (P<0.01). The levels of interleukin 1β (IL-1β) in the poor prognosis group were higher than those in the good prognosis group (P>0.05), and the platelet (PLT), albumin (ALB), and hemoglobin (Hb) levels were lower in the poor prognosis group (P<0.01). The IL-8 levels in the severe sepsis group were higher than those in the sepsis group (P<0.05). Multiple logistic regression analysis suggested that lower Hb levels, ALB levels, peak PLT counts, and higher IL-1β levels were independent risk factors for poor prognosis in children with sepsis.

CONCLUSION

Lower Hb, ALB, and PLT counts and elevated IL-1β are independent risk factors for poor prognosis in children with sepsis.

Elevated Activated Partial Thromboplastin Time as a Predictor of 28-Day Mortality in Sepsis-Associated Acute Kidney Injury: A Retrospective Cohort Analysis

Purpose

To address the critical mortality rates among sepsis-associated acute kidney injury (SA-AKI) patients, early prognosis is vital. This study investigates the relationship between coagulation indices and the 28-day mortality rate in patients with SA-AKI.

Patients and Methods

This study was a retrospective cohort analysis including patients with SA-AKI admitted to the First Hospital of Fujian Medical University as a training cohort (n = 119) and patients admitted to the Third People's Hospital of Fujian University of Traditional Chinese Medicine as a validation cohort (n = 51). We examined the relationship between coagulation indices and 28-day mortality in SA-AKI, the cumulative mortality at different activated partial thromboplastin time (APTT) levels, and the nonlinear relationship between APTT and 28-day mortality. Receiver operating characteristic curves were plotted, and the area under the curve was calculated to assess the predictive power of APTT. Finally, subgroup analyses were performed to assess the robustness of the association.

Results

Overall, 119 participants with a mean±standard deviation age of 70.47±15.20 years were included in the training cohort: 54 died, 65 survived. According to univariate and multivariate COX regression analyses, APACHE II score, CRP level, Lac level, and APTT level were independent risk factors for 28-day adverse prognosis. After controlling for some variables, an elevated baseline APTT (≥ 37.7 s) was associated with an elevated risk of 28-day mortality (HR, 1.017; 95% CI, 1.001-1.032), and Kaplan-Meier analyses further confirmed the increased mortality in the group with a higher APTT. The same results were shown when the validation cohort was analyzed (HR, 1.024; 95% CI, 0.958-1.096). Subgroup analyses showed the stability of the association between APTT and poor prognosis in SA-AKI.

Conclusion

In essence, APTT elevation is synonymous with increased 28-day mortality rates, indicating a poor prognosis in SA-AKI scenarios.

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

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

A proposed framework for advancing acute kidney injury risk stratification and diagnosis in children: a report from the 26th Acute Disease Quality Initiative (ADQI) conference

Acute kidney injury (AKI) in children is associated with increased morbidity, reduced health-related quality of life, greater resource utilization, and higher mortality. Improvements in the timeliness and precision of AKI diagnosis in children are needed. In this report, we highlight existing, novel, and on-the-horizon diagnostic and risk-stratification tools for pediatric AKI, and outline opportunities for integration into clinical practice. We also summarize pediatric-specific high-risk diagnoses and exposures for AKI, as well as the potential role of real-time risk stratification and clinical decision support to improve outcomes. Lastly, the key characteristics of important pediatric AKI phenotypes will be outlined. Throughout, we identify key knowledge gaps, which represent prioritized areas of focus for future research that will facilitate a comprehensive, timely and personalized approach to pediatric AKI diagnosis and management.

Acute kidney injury biomarker olfactomedin 4 predicts furosemide responsiveness

BACKGROUND

Acute kidney injury (AKI) is associated with increased morbidity and mortality in critically ill patients. Olfactomedin 4 (OLFM4), a secreted glycoprotein expressed in neutrophils and stressed epithelial cells, is upregulated in loop of Henle (LOH) cells following AKI. We hypothesized that urine OLFM4 (uOLFM4) will increase in patients with AKI and may predict furosemide responsiveness.

METHODS

Urine from critically ill children was collected prospectively and tested for uOLFM4 concentrations with a Luminex immunoassay. Severe AKI was defined by KDIGO (stage 2/3) serum creatinine criteria. Furosemide responsiveness was defined as > 3 mL/kg/h of urine output in the 4 h after a 1 mg/kg IV furosemide dose administered as part of standard of care.

RESULTS

Fifty-seven patients contributed 178 urine samples. Irrespective of sepsis status or AKI cause, uOLFM4 concentrations were higher in patients with AKI (221 ng/mL [IQR 93-425] vs. 36 ng/mL [IQR 15-115], p = 0.007). uOLFM4 concentrations were higher in patients unresponsive to furosemide (230 ng/mL [IQR 102-534] vs. 42 ng/mL [IQR 21-161], p = 0.04). Area under the receiver operating curve for association with furosemide responsiveness was 0.75 (95% CI, 0.60-0.90).

CONCLUSIONS

AKI is associated with increased uOLFM4. Higher uOLFM4 is associated with a lack of response to furosemide. Further testing is warranted to determine whether uOLFM4 could identify patients most likely to benefit from earlier escalation from diuretics to kidney replacement therapy to maintain fluid balance. A higher resolution version of the Graphical abstract is available as Supplementary information.

Serum renin and prorenin concentrations predict severe persistent acute kidney injury and mortality in pediatric septic shock

BACKGROUND

Studies in critically ill adults demonstrate associations between serum renin concentrations (a proposed surrogate for renin-angiotensin-aldosterone system dysregulation) and poor outcomes, but data in critically ill children are lacking. We assessed serum renin + prorenin concentrations in children with septic shock to determine their predictive ability for acute kidney injury (AKI) and mortality.

METHODS

We conducted a secondary analysis of a multicenter observational study of children aged 1 week to 18 years admitted to 14 pediatric intensive care units (PICUs) with septic shock and residual serum available for renin + prorenin measurement. Primary outcomes were development of severe persistent AKI (≥ KDIGO stage 2 for ≥ 48 h) in the first week and 28-day mortality.

RESULTS

Among 233 patients, day 1 median renin + prorenin concentration was 3436 pg/ml (IQR 1452-6567). Forty-two (18%) developed severe persistent AKI and 32 (14%) died. Day 1 serum renin + prorenin predicted severe persistent AKI with an AUROC of 0.75 (95% CI 0.66-0.84, p < 0.0001; optimal cutoff 6769 pg/ml) and mortality with an AUROC of 0.79 (95% CI 0.69-0.89, p < 0.0001; optimal cutoff 6521 pg/ml). Day 3/day 1 (D3:D1) renin + prorenin ratio had an AUROC of 0.73 (95% CI 0.63-0.84, p < 0.001) for mortality. On multivariable regression, day 1 renin + prorenin > optimal cutoff retained associations with severe persistent AKI (aOR 6.8, 95% CI 3.0-15.8, p < 0.001) and mortality (aOR 6.9, 95% CI 2.2-20.9, p < 0.001). Similarly, D3:D1 renin + prorenin > optimal cutoff was associated with mortality (aOR 7.6, 95% CI 2.5-23.4, p < 0.001).

CONCLUSIONS

Children with septic shock have very elevated serum renin + prorenin concentrations on PICU admission, and these concentrations, as well as their trend over the first 72 h, predict severe persistent AKI and mortality. A higher resolution version of the Graphical abstract is available as Supplementary information.

Acute kidney injury in pediatric toxic shock syndrome is associated with worse clinical course in the intensive care unit

To explore the prevalence, severity, nature, and significance of acute kidney injury (AKI) among children admitted to the pediatric intensive care unit (PICU) with toxic shock syndrome (TSS). Bi-center, retrospective observational study. Children admitted for TSS to two intensive care units from 2009-2022 were included. We identified 41 children (median age 5 years, 46% females) who met the Centers for Disease Control and Prevention (CDC) definitions of TSS. Staphylococcal TSS accounted for 63% of the patients and Streptococcal TSS accounted for the remaining 37%. AKI was diagnosed in 24 (59%) (stage 1: n = 6 [15% of total], stage 2: n = 10 [24%], and stage 3: n = 8 [20%]). The worst creatinine level was measured during the first day of admission in 34 (83%) patients. The median duration of AKI was 2 days. Creatinine normalized by hospital discharge in all cases. Patients with AKI had a longer intensive care unit stay than those without AKI (6 vs. 3 days, respectively, p = 0.01), needed more respiratory support (87% vs. 47%, p = 0.002), had fewer 28 ventilation-free days (25 vs. 28, p = 0.01), fewer vasopressor-free days (25 vs. 28, p = 0.001), and received more blood products (p = 0.03).    Conclusion: Children admitted to the PICU with TSS, show a high prevalence of AKI at presentation. Creatinine levels and clearance normalize by hospital discharge in most cases. AKI in the setting of TSS could be used as an early marker for illness severity and a predictor of a more complex course. What is Known: • TSS is characterized according to the CDC by specific sets of clinical signs and symptoms in conjunction with specific laboratory findings one of which is AKI. • AKI is associated with worse outcomes in critically ill patients in general and in septic patients in particular. What is New: • AKI is found in about 60% of all patients admitted to the PICU with a diagnosis of TSS and hence is an important defining criteria. • AKI in the setting of TSS is associated with a more complex illness course and can serve as an early marker predicting such a course.

Fluid Overload Precedes and Masks Cryptic Kidney Injury in Pediatric Acute Respiratory Distress Syndrome

OBJECTIVES

Given the complex interrelatedness of fluid overload (FO), creatinine, acute kidney injury (AKI), and clinical outcomes, the association of AKI with poor outcomes in critically ill children may be underestimated due to definitions used. We aimed to disentangle these temporal relationships in a large cohort of children with acute respiratory distress syndrome (ARDS).

DESIGN

Retrospective cohort study.

SETTING

Quaternary care PICU.

PATIENTS

Seven hundred twenty intubated children with ARDS between 2011 and 2019.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Daily fluid balance, urine output (UOP), and creatinine for days 1-7 of ARDS were retrospectively abstracted. A subset of patients had angiopoietin 2 (ANGPT2) quantified on days 1, 3, and 7. Patients were classified as AKI by Kidney Disease Improving Global Outcomes (KDIGO) stage 2/3 then grouped by timing of AKI onset (early if days 1-3 of ARDS, late if days 4-7 of ARDS, persistent if both) for comparison of PICU mortality and ventilator-free days (VFDs). A final category of "Cryptic AKI" was used to identify subjects who met KDIGO stage 2/3 criteria only when creatinine was adjusted for FO. Outcomes were compared between those who had Cryptic AKI identified by FO-adjusted creatinine versus those who had no AKI. Conventionally defined AKI occurred in 26% of patients (early 10%, late 3%, persistent 13%). AKI was associated with higher mortality and fewer VFDs, with no differences according to timing of onset. The Cryptic AKI group (6% of those labeled no AKI) had higher mortality and fewer VFDs than patients who did not meet AKI with FO-adjusted creatinine. FO, FO-adjusted creatinine, and ANGPT2 increased 1 day prior to meeting AKI criteria in the late AKI group.

CONCLUSIONS

AKI was associated with higher mortality and fewer VFDs in pediatric ARDS, irrespective of timing. FO-adjusted creatinine captures a group of patients with Cryptic AKI with outcomes approaching those who meet AKI by traditional criteria. Increases in FO, FO-adjusted creatinine, and ANGPT2 occur prior to meeting conventional AKI criteria.

Sepsis-associated acute kidney injury: consensus report of the 28th Acute Disease Quality Initiative workgroup

Sepsis-associated acute kidney injury (SA-AKI) is common in critically ill patients and is strongly associated with adverse outcomes, including an increased risk of chronic kidney disease, cardiovascular events and death. The pathophysiology of SA-AKI remains elusive, although microcirculatory dysfunction, cellular metabolic reprogramming and dysregulated inflammatory responses have been implicated in preclinical studies. SA-AKI is best defined as the occurrence of AKI within 7 days of sepsis onset (diagnosed according to Kidney Disease Improving Global Outcome criteria and Sepsis 3 criteria, respectively). Improving outcomes in SA-AKI is challenging, as patients can present with either clinical or subclinical AKI. Early identification of patients at risk of AKI, or at risk of progressing to severe and/or persistent AKI, is crucial to the timely initiation of adequate supportive measures, including limiting further insults to the kidney. Accordingly, the discovery of biomarkers associated with AKI that can aid in early diagnosis is an area of intensive investigation. Additionally, high-quality evidence on best-practice care of patients with AKI, sepsis and SA-AKI has continued to accrue. Although specific therapeutic options are limited, several clinical trials have evaluated the use of care bundles and extracorporeal techniques as potential therapeutic approaches. Here we provide graded recommendations for managing SA-AKI and highlight priorities for future research.

Subphenotypes of acute kidney injury in children

PURPOSE OF REVIEW

The purpose of this review is to describe acute kidney injury (AKI) phenotypes in children.

RECENT FINDINGS

AKI is a heterogenous disease that imposes significant morbidity and mortality on critically ill and noncritically ill patients across the age spectrum. As our understanding of AKI and its association with outcomes has improved, it is becoming increasingly apparent that there are distinct AKI subphenotypes that vary by cause or associated conditions. We have also learned that severity, duration, and repeated episodes of AKI impact outcomes, and that integration of novel urinary biomarkers of tubular injury can also reveal unique subphenotypes of AKI that may not be otherwise readily apparent.

SUMMARY

Studies that further delineate these unique AKI subphenotypes are needed to better understand the impact of AKI in children. Further delineation of these phenotypes has both prognostic and therapeutic implications.

Subphenotypes of acute kidney injury in adults

PURPOSE OF REVIEW

Acute kidney injury is a heterogeneous syndrome and as such is associated with multiple predisposing conditions and causes all of which affect outcomes. Such heterogeneity may conceal the potential benefit of therapies when generally applied to patients with acute kidney injury (AKI). The discovery of pathophysiology-based subphenotypes could be of benefit in allocating current and future therapies to specific groups.

RECENT FINDINGS

Clinical subphenotypes group patients into categories according to predisposing factors, disease severity, and trajectory. These may be helpful in assessing patient outcomes. Analyses of existing databases have revealed biological subphenotypes that are characterized by levels of biomarkers indicative of hyperinflammation and endothelial injury. Patients with increased levels of these biomarkers display higher mortality rates compared with those with lower levels and there is potential that this group might respond differently to therapies. However, challenges remain in the validation, generalizability, and application of these subphenotypes.

SUMMARY

Subphenotyping may help reduce heterogeneity under the umbrella term of acute kidney injury. Despite challenges remain, the identification of AKI subphenotypes has opened the potential of AKI research focused on better targeted therapies.

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

IMPORTANCE

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

OBJECTIVE

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

EVIDENCE REVIEW

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

FINDINGS

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

CONCLUSIONS AND RELEVANCE

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

Olfactomedin 4 as a novel loop of Henle-specific acute kidney injury biomarker

Acute kidney injury (AKI) is associated with morbidity and mortality. Urinary biomarkers may disentangle its clinical heterogeneity. Olfactomedin 4 (OLFM4) is a secreted glycoprotein expressed in stressed neutrophils and epithelial cells. In septic mice, OLFM4 expression localized to the kidney's loop of Henle (LOH) and was detectable in the urine. We hypothesized that urine OLFM4 (uOLFM4) will be increased in patients with AKI and sepsis. Urine from critically ill pediatric patients was obtained from a prospective study based on AKI and sepsis status. uOLFM4 was quantified with a Luminex immunoassay. AKI was defined by KDIGO severe criteria. Sepsis status was extracted from the medical record based on admission diagnosis. Immunofluorescence on pediatric kidney biopsies was performed with NKCC2, uromodulin and OLFM4 specific antibodies. Eight patients had no sepsis, no AKI; 7 had no sepsis but did have AKI; 10 had sepsis, no AKI; 11 had sepsis and AKI. Patients with AKI had increased uOLFM4 compared to no/stage 1 AKI (p = 0.044). Those with sepsis had increased uOLFM4 compared to no sepsis (p = 0.026). uOLFM4 and NGAL were correlated (r2 0.59, 95% CI 0.304-0.773, p = 0.002), but some patients had high uOLFM4 and low NGAL, and vice versa. Immunofluorescence on kidney biopsies demonstrated OLFM4 colocalization with NKCC2 and uromodulin, suggesting expression in the thick ascending LOH (TALH). We conclude that AKI and sepsis are associated with increased uOLFM4. uOLFM4 and NGAL correlated in many patients, but was poor in others, suggesting these markers may differentiate AKI subgroups. Given OLFM4 colocalization to human TALH, we propose OLFM4 may be a LOH-specific AKI biomarker.

Subphenotypes in acute kidney injury: a narrative review

Acute kidney injury (AKI) is a frequently encountered syndrome especially among the critically ill. Current diagnosis of AKI is based on acute deterioration of kidney function, indicated by an increase in creatinine and/or reduced urine output. However, this syndromic definition encompasses a wide variety of distinct clinical features, varying pathophysiology, etiology and risk factors, and finally very different short- and long-term outcomes. Lumping all AKI together may conceal unique pathophysiologic processes specific to certain AKI populations, and discovering these AKI subphenotypes might help to develop targeted therapies tackling unique pathophysiological processes. In this review, we discuss the concept of AKI subphenotypes, current knowledge regarding both clinical and biomarker-driven subphenotypes, interplay with AKI subphenotypes and other ICU syndromes, and potential future and clinical implications.

Acute kidney injury in critically Ill children and young adults with suspected SARS-CoV2 infection

BACKGROUND

We aimed to study the association of suspected versus confirmed infection with the novel SARS-CoV2 virus with the prevalence of acute kidney injury (AKI) in critically ill children.

METHODS

Sequential point-prevalence study of children and young adults aged 7 days to 25 years admitted to intensive care units under investigation for SARS-CoV2 infection. AKI was staged in the first 14 days of enrollment using KDIGO creatinine-based staging. SARS-CoV2 positive (CONFIRMED) were compared to SUSPECTED (negative or unknown). Outcome data was censored at 28-days.

RESULTS

In 331 patients of both sexes, 179 (54.1%) were CONFIRMED, 4.2% (14) died. AKI occurred in 124 (37.5%) and severe AKI occurred in 63 (19.0%). Incidence of AKI in CONFIRMED was 74/179 (41.3%) versus 50/152 (32.9%) for SUSPECTED; severe AKI occurred in 35 (19.6%) of CONFIRMED and 28 (18.4%) of SUSPECTED. Mortality was 6.2% (n = 11) in CONFIRMED, but 9.5% (n = 7) in those CONFIRMED with AKI. On multivariable analysis, only Hispanic ethnicity (relative risk 0.5, 95% CI 0.3-0.9) was associated with less AKI development among those CONFIRMED.

CONCLUSIONS

AKI and severe AKI occur commonly in critically ill children with SARS-CoV2 infection, more than double the historical standard. Further investigation is needed during this continuing pandemic to describe and refine the understanding of pediatric AKI epidemiology and outcomes.

TRIAL REGISTRATION

NCT01987921.

IMPACT

What is the key message of the article? AKI occurs in children exposed to the novel SARS-CoV2 virus at high prevalence (~40% with some form of AKI and 20% with severe AKI). What does it add to the existing literature? Acute kidney injury (AKI) occurs commonly in adult patients with SARS-CoV2 (COVID), very little data describes the epidemiology of AKI in children exposed to the virus. What is the impact? A pediatric vaccine is not available; thus, the pandemic is not over for children. Pediatricians will need to manage significant end-organ ramifications of the novel SARS-CoV2 virus including AKI.

Risk Classification and Subphenotyping of Acute Kidney Injury: Concepts and Methodologies

Acute kidney injury (AKI) is a complex syndrome with a paucity of therapeutic development. One aspect that could explain the lack of implementation science in the AKI field is the vast heterogeneity of the AKI syndrome, which hinders precise therapeutic applications for specific AKI subpopulations. In this context, there is a consensual focus of the scientific community toward the development and validation of tools to better subphenotype AKI and therefore facilitate precision medicine approaches. The subphenotyping of AKI requires the use of specific methodologies suitable for interrogation of multimodal data inputs from different sources such as electronic health records, organ support devices, and/or biospecimens and tissues. Over the past years, the surge of artificial intelligence applied to health care has yielded novel machine learning methodologies for data acquisition, harmonization, and interrogation that can assist with subphenotyping of AKI. However, one should recognize that although risk classification and subphenotyping of AKI is critically important, testing their potential applications is even more important to promote implementation science. For example, risk-classification should support actionable interventions that could ameliorate or prevent the occurrence of the outcome being predicted. Furthermore, subphenotyping could be applied to predict therapeutic responses to support enrichment and adaptive platforms for pragmatic clinical trials.

The Neglected Price of Pediatric Acute Kidney Injury: Non-renal Implications

Preclinical models and emerging translational data suggest that acute kidney injury (AKI) has far reaching effects on all other major organ systems in the body. Common in critically ill children and adults, AKI is independently associated with worse short and long term morbidity, as well as mortality, in these vulnerable populations. Evidence exists in adult populations regarding the impact AKI has on life course. Recently, non-renal organ effects of AKI have been highlighted in pediatric AKI survivors. Given the unique pediatric considerations related to somatic growth and neurodevelopmental consequences, pediatric AKI has the potential to fundamentally alter life course outcomes. In this article, we highlight the challenging and complex interplay between AKI and the brain, heart, lungs, immune system, growth, functional status, and longitudinal outcomes. Specifically, we discuss the biologic basis for how AKI may contribute to neurologic injury and neurodevelopment, cardiac dysfunction, acute lung injury, immunoparalysis and increased risk of infections, diminished somatic growth, worsened functional status and health related quality of life, and finally the impact on young adult health and life course outcomes.