Acute kidney injury in critically ill children: Risk factors and outcomes

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.

Risk factors for development of acute kidney injury and acute kidney disease in critically ill children

BACKGROUND

Acute kidney injury (AKI) is common among critically ill children and these children are at risk of developing acute kidney disease (AKD).

METHODS

A prospective cohort study was conducted on children aged > 1 month to ≤ 18 years old admitted to the pediatric intensive care unit (ICU) of Hong Kong Children's Hospital from 6/2020 to 6/2021. The incidences and risk factors of both AKI and AKD were determined.

RESULTS

There were 254 eligible admissions (58.3% in males, with a median age of 4.9 [9.7] years). The overall AKI incidence was 41.7% and 56% of children who remained hospitalized in the pediatric  ICU for ≥ 7 days after acquiring AKI developed AKD. Cardiac surgery, bone marrow transplantation and requirement of inotropes were risk factors for both AKI and AKD. The requirement of non-invasive ventilation [relative risk (RR): 2.625 (1.361, 5.064)], total medication dose [RR 1.006 (1.002, 1.010)] and maximal medication intensity [RR 1.154 (1.038, 1.283)] were additional determinants of AKI. Factors indicating more severe AKI and AKI progression were predictive of AKD development. The overall mortality in the pediatric ICU was 3.1%. AKI was significantly associated with mortality (p < 0.001), longer length of hospitalization in the pediatric ICU (p < 0.001) and hospital stay (p < 0.001). AKD was associated with a lower estimated glomerular filtration rate at discharge from the pediatric ICU (p = 0.036).

CONCLUSION

AKI and AKD were common among critically ill children, and were associated with significant morbidity and mortality. Few modifiable risk factors, especially those related to nephrotoxic medication exposure, were associated with AKI development and AKD progression.

Comparative Analysis of Intensive Care Prognosis Scoring Systems and Acute Kidney Injury Scores (AKIN and pRIFLE) in Critically Ill Children

The development of AKI (acute kidney injury) in critically ill patients in pediatric intensive care units (PICUs) is one of the most important factors affecting mortality. There are scoring modalities used to predict mortality in PICUs. We compared the AKIN (Acute Kidney Injury Network) and pRIFLE (pediatric risk, injury, failure, loss, and end stage) AKI classifications and PICU scoring modalities in this study. Methods: A total of 716 children, whose serum creatinine levels were within the normal limits at the time of admission to the PICU between January 2018 and December 2020, were included. Along with the demographic and clinical variables, AKIN and pRIFLE classifications were recorded at the most advanced stage of AKI. Along with the PIM-2, PRISM III, and PELOD-2 scores, the highest value of the pSOFA score was recorded. Results: According to the pRIFLE and AKIN classifications, 62 (8.7%) patients developed kidney injury, which had a statistically significant effect on mortality. The occurrence of renal injury was found to be statistically strongly and significantly correlated with high PRISM III, PELOD-2, and pSOFA scores. When the stages of kidney injury according to the AKIN criteria were compared with the PRISM III, PELOD 2, and pSOFA scores, a significant difference was found between the patients who did not develop AKI and those who developed stage 1, stage 2, and stage 3 kidney injury. For the PRISM III, PELOD 2, and pSOFA scores, there were no significant differences between the stages according to the AKIN criteria. A substantial difference was discovered between the patients who did not develop AKI and those who were in the risk, injury, and failure plus loss stages according to the pRIFLE criteria. According to the PIM-2 ratio and pRIFLE criteria, there was a statistically significant difference between patients in the injury and failure plus loss stages and those who did not develop AKI. Conclusions: Our study is the first pediatric study to show a substantial correlation between the variables associated with the PICU scoring modalities in critically ill children with AKI. Identifying the risk factors for the development of AKI and planning antimicrobial regimens for patients with favorable prognoses at the time of PICU admission could lower mortality rates.

A Retrospective Analysis of Risk Factors and Impact of Acute Kidney Injury in Critically Ill Children

BACKGROUND

Acute kidney injury (AKI) is a serious clinical condition in critically ill children and is associated with worse outcomes. A few pediatric studies focused on the risk factors of AKI. We aimed to identify the incidence, risk factors, and outcomes of AKI in the pediatric intensive care unit (PICU).

PATIENTS AND METHODS

All the patients admitted to PICU over a period of 20 months were included. We compared both groups the risk factors between AKI and non-AKI.

RESULTS

A total of 63 patients (17.5%) of the 360 patients developed AKI during PICU stay. The presence of comorbidity, diagnosis of sepsis, increased PRISM III score, and positive renal angina index were found to be risk factors for AKI on admission. Thrombocytopenia, multiple organ failure syndrome, the requirement of mechanical ventilation, use of inotropic drugs, intravenous iodinated contrast media, and exposure to an increased number of nephrotoxic drugs were independent risk factors during the hospital stay. The patients with AKI had a lower renal function on discharge and had worse overall survival.

CONCLUSIONS

AKI is prevalent and multifactorial in critically sick children. The risk factors of AKI may be present on admission and during the hospital stay. AKI is related to prolonged mechanical ventilation days, longer PICU stays, and a higher mortality rate. Based on the presented results early prediction of AKI and consequent modification of nephrotoxic medication may generate positive effects on the outcome of critically ill children.

Neutrophil Gelatinase-Associated Lipocalin as a Predictor of Acute Kidney Injury in Children With Shock: A Prospective Study

BACKGROUND

The current definition of acute kidney injury (AKI) is based on serum creatinine (SrCr) and urine output, limited by delayed identification of such patients. Plasma neutrophil gelatinase-associated lipocalin (NGAL) is considered an early diagnostic and highly predictive biomarker of AKI.

OBJECTIVE

To determine the diagnostic accuracy of NGAL for AKI compared with creatinine clearance for early detection of AKI in children with shock receiving inotropic support.

METHODS

Critically ill children requiring inotropic support in the pediatric intensive care unit were enrolled prospectively. SrCr and NGAL values were obtained three times at six, 12, and 48 hours after vasopressor initiation. Patients with AKI were defined as having loss of >25% renal function based on creatinine clearance within 48 hours. NGAL level of more than 150 ng/dl was suggestive of the diagnosis of AKI. Receiver operator characteristic curves were generated for NGAL and SrCr to compare the predictive ability of both at 0, 12, and 48 hours of starting vasopressor support.  Results: A total of 94 patients were enrolled. The mean age was 43±50.95 months. Most common primary diagnoses were related to the cardiovascular system (46%). Twenty-nine patients (31%) died during the hospital stay. Thirty-four patients (36%) developed AKI within 48 hours following shock. The area under the curve (AUC) for NGAL at a cutoff of 150 ng/ml was 0.70, 0.74, and 0.73 at six-hour, 12-hour, and 48-hour follow-up, respectively. NGAL had a sensitivity of 85.3% and specificity of 50% at 0 hours of follow-up for diagnosis of AKI.

CONCLUSION

Serum NGAL has better sensitivity and AUC compared to SrCr for early diagnosis of AKI in children admitted with shock.

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.

The Epidemiology and Management of Pediatric AKI in Asia

Because of the lack of early recognition and referral, the incidence of pediatric acute kidney injury (AKI) in Asia still is underestimated. Although each diagnostic criteria has its own merits, the Kidney Disease Improving Global Outcomes classification now is widely accepted. In Asia, the spectrum of pediatric AKI is wide-ranging, from pediatric AKI in highly sophisticated tertiary-care pediatric intensive care units in resource-rich regions due to advanced procedures such as transplantation, cardiac surgery, and other hospital-acquired causes, to primary care preventable causes, such as infectious diseases, snakebite, and so forth in rural parts of the developing world. The development and application of novel biomarkers, concepts such as the Renal Angina Index and advanced renal replacement therapy have revolutionized the era of treating AKI, but the cost and feasibility are the key determinants, especially in rural areas. In view of availability and expenses, peritoneal dialysis should be the first choice in less-developed areas, however, because of various barriers, it still needs more effort. Effective educational steps to both medical carers and families are needed urgently.

Acute renal failure in children. Multicenter prospective cohort study in medium-complexity intensive care units from the Colombian southeast

BACKGROUND

Acute kidney injury is frequent in critically ill children; however, it varies in causality and epidemiology according to the level of patient care complexity. A multicenter prospective cohort study was conducted in four medium-complexity pediatric intensive care units from the Colombian southeast aimed to estimate the clinical prognosis of patients with diagnosis of acute kidney injury.

METHODS

We included children >28 days and <18 years of age, who were admitted with diagnosis of acute kidney injury classified by Kidney Disease Improving Global Outcomes (KDIGO), during the period from January to December 2017. Severe acute kidney injury was defined as stage 2 and stage 3 classifications. Maximum KDIGO was evaluated during the hospital stay and follow up. Length of hospital stay, use of mechanical ventilation and vasoactive drugs, use of renal replacement therapy, and mortality were assessed until discharge.

RESULTS

Prevalence at admission of acute kidney injury was 5.2% (95%CI 4.3% to 6.2%). It was found that 71% of the patients had their maximum KDIGO on day one; an increment in the maximum stage of acute kidney injury increased the pediatric intensive care unit stay. Patients with maximum KDIGO 3 were associated with greater use of mechanical ventilation (47%), compared with maximum KDIGO 2 (37%) and maximum KDIGO 1 (16%). Eight patients with maximum KDIGO 2 and 14 with maximum KDIGO 3 required renal replacement therapy. Mortality was at 11.8% (95%CI 6.4% to 19.4%).

CONCLUSION

Acute kidney injury, established and classified according to KDIGO as severe and its maximum stage, was associated with worse clinical outcomes; early therapeutic efforts should focus on preventing the progression to severe stages.

eResearch in acute kidney injury: a primer for electronic health record research

Acute kidney injury (AKI) has a significant impact on patient morbidity and mortality as well as overall health care costs. eResearch, which integrates information technology and information management to optimize research strategies, provides a perfect platform for necessary ongoing AKI research. With the recent adoption of a widely accepted definition of AKI and near-universal use of electronic health records, eResearch is becoming an important tool in AKI research. Conducting eResearch in AKI should ideally be based on a relatively uniform methodology. This article is the first of its kind to describe a methodology for pursuing eResearch specific to AKI and includes an illustrative database example for critically ill patients. We discuss strategies for using serum creatinine and urine output in large databases to identify and stage AKI and ways to interpolate missing values and validate data. Issues specific to the pediatric population include variation in serum creatinine with growth, varied severity of illness scoring systems and medication dosage based on weight. Many of these same strategies used to optimize AKI eResearch can be applicable to real-time AKI alerts with potential integration of additional clinical variables.

Spectrum and Immediate Outcome of Acute Kidney Injury in a Pediatric Intensive Care Unit: A Snapshot Study from Indian Subcontinent

Background and aims

Acute kidney injury (AKI) became an important cause of mortality and morbidity in critically ill children, despite advancement in its management. In developing countries etiology of AKI are different from that of developed countries.

Materials and methods

This observational study was carried out in pediatric intensive care unit (PICU) in 2 months to18 years of critically ill children. Kidney injury was defined and categorized by the pRIFLE criteria.

Results

Out of 361children, 86 children (23.8%) developed AKI at some point during admission, 275 children (age and sex matched) who did not develop kidney injury during hospitalization served as non-AKI children. Maximum cases of AKI were seen in 1–5 years of age. Maximum children of AKI were of viral encephalitis (n = 43, 50.0%) followed by scrub typhus (n = 14, 16.3%). Risk factors for the development of AKI were shock, PRISM score and longer hospital stay. In our study the mortality in AKI children (n = 30, 34.8%) was significantly higher (p = 0.005) as compared to non-AKI children (n = 56, 20.3%)). Duration on mechanical ventilation, PICU stay and hospital stay were also significantly (p = 0.001) higher in AKI children.

Conclusion

AKI is common in critically ill children and associated with high mortality and morbidity.

How to cite this article

Bharat A, Mehta A, Tiwari HC, Sharma B, Singh A, Singh V. Spectrum and Immediate Outcome of Acute Kidney Injury in a Pediatric Intensive Care Unit: A Snapshot Study from Indian Subcontinent. Indian J Crit Care Med 2019;23(8):352-355.

Acute kidney injury among paediatric emergency room admissions in a tertiary hospital in South West Nigeria: a cohort study

Background

Epidemiological data on paediatric acute kidney injury (AKI) in sub-Saharan Africa are limited and largely retrospective. We performed a prospective study of AKI among patients admitted through the emergency room.

Methods

Children admitted to the post-neonatal emergency room of the University College Hospital, Ibadan, Nigeria between February 2016 and January 2017 were studied. AKI was defined by Kidney Disease: Improving Global Outcomes serum creatinine criteria. AKI ascertainment relied on serum creatinine measurements carried out in routine care by post-admission Day 1. We compared in-hospital mortality by post-admission Day 7 for patients with and without AKI (no-AKI).

Results

Of the 1344 children admitted to the emergency room, 331 were included in the study. AKI occurred in 112 patients (33.8%) with a median age of 3.1 years [interquartile range (IQR) 0.9–9.4] and was Stage 3 in 50.5% of the cases. The no-AKI group had a median age of 1.8 (IQR 0.7–5.8) years. The underlying diagnoses in patients with AKI were sepsis (33.0%), malaria (12.5%) and primary renal disorders (13.4%). Twenty-four of the patients with AKI underwent dialysis: haemodialysis in 20 and peritoneal dialysis in 4. By Day 7 of admission, 7 of 98 (7.1%) patients in the AKI group had died compared with 5 of 175 (2.9%) patients in the no-AKI group [odds ratio 2.6 (95% confidence interval 0.8–8.5)]. Outcome data were not available for 58 (17.5%) patients.

Conclusions

AKI is common among paediatric emergency room admissions in a tertiary care hospital in sub-Saharan Africa. It is associated with high mortality risk that may be worse in settings without dialysis.

Association between pediatric Risk, Injury, Failure, Loss and End Stage Renal Disease score and mortality in a pediatric intensive care unit: a retrospective study

OBJECTIVE

To evaluate the association between acute kidney injury through the pediatric Risk, Injury, Failure, Loss and End Stage Renal Disease score and mortality in a pediatric intensive care unit.

METHODS

This retrospective cohort study assessed all children admitted to the pediatric intensive care unit of a reference hospital in Brazil from January to December 2016. Patients were screened for the presence of acute kidney injury through the pediatric Risk, Injury, Failure, Loss and End Stage Renal Disease score. Patients were subdivided into the stages of Risk, Injury and Kidney Failure.

RESULTS

The sample comprised 192 children, of whom 45.8% developed acute kidney injury, with 79.5% of the cases identified up to 72 hours after admission. Patients with acute kidney injury showed a 3.74 increase risk of death (p = 0.01) than the control group. Patients with kidney failure had a mortality rate that was 8.56 times greater than that of the remaining sample (p < 0.001). The variables that were associated with the stages of acute kidney injury were nephrotoxic drugs (p = 0.025), renal replacement therapy (p < 0.001), vasoactive drugs (p < 0.001), pediatric risk of mortality 2 score (p = 0.023), fluid overload (p = 0.005), pediatric intensive care unit length of stay (p = 0.001) and death (p < 0.001).

CONCLUSION

In this study, the pediatric Risk, Injury, Failure, Loss and End Stage Renal Disease score proved to be a useful tool for the early identification of severely ill children with acute kidney injury, showing an association with mortality. We thus suggest its use for pediatric intensive care unit patient admission.

Impact of acute kidney injury on long-term mortality and progression to chronic kidney disease among critically ill children

Objectives:

To determine the 2-year outcome of acute kidney injury (AKI) following admission to pediatric critical care units (PICU).

Methods:

A retrospective cohort study was conducted between January 2012 and December 2013. We followed 131 children admitted to PICU, King Abdulaziz University Hospital, Jeddah, Kingdom of Saudi Arabia with a diagnosis of AKI, based on pRIFLE (pediatric risk, injury, failure, loss, and end-stage renal disease), for 2 years. During the study period, 46 children died and 38 of survivors completed the follow-up. Factors affecting long-term progression to chronic kidney disease were also evaluated.

Results:

The 2-year mortality was more than 40%. The main determinant of the 2-year mortality was the pediatric risk of mortality (PRISM) score, which increased the risk of mortality by 6% per each one score (adjusted odds ratio, 1.06: 95% confidence interval: 1.00-1.11). By the end of the 2 years, 33% of survivors had reduction in the glomerular filtration rate and proteinuria, and 73% were hypertensive. Patients with more severe renal impairment at admission, based on the pRIFLE criteria, had higher mortality rate. This association, however, was not independent since it was influenced by baseline disease severity (PRISM score).

Conclusion:

Large proportion of patients admitted to PICU with AKI either died during the first 2 months of follow-up or developed long-term complications. The severity of AKI, however, was not an independent risk factor for mortality.

Incidence, risk factors and outcome of acute kidney injury in critically ill children - a developing country perspective

BACKGROUND

Acute kidney injury (AKI) is common in critically ill children and is associated with poor outcome.

OBJECTIVE

To study the incidence, risk factors and outcome of AKI in children admitted to paediatric intensive care unit (PICU) of a developing country.

MATERIALS AND METHODS

This prospective observational study was conducted in a tertiary care PICU over one-year period. Critically ill children aged from 2 months to 18 years were included. RIFLE criteria based on GFR, and urine output was used for categorisation.

RESULTS

Of 380 children, 53 children (14%) had AKI (met any of the RIFLE criteria). The most common diagnoses underlying AKI were acute lower respiratory tract infection, CNS illness and severe dehydration. Subjects with AKI had a higher PRISM score (>10) at admission, longer duration of stay and high mortality. Significant risk factors for AKI following multivariate analysis were: age 1-5, PRISM score (>10) at admission, shock, infection, thrombocytopenia, hypo-albuminaemia and multi-organ dysfunction. Twenty-six of 53 subjects fulfilled the maximum RIFLE criteria within 72 h after admission and the mean (SD) time to first RIFLE attend was 1.6 (1.2) day. Subjects with AKI (RIFLE criteria) had 4.5 times higher mortality than those without AKI (36 vs 8%, P< etc).

CONCLUSION

A high incidence of AKI was noted in the PICU that was associated with high mortality. The RIFLE criterion is an effective tool which can be used not only for predicting the outcomes, but may help in the early identification of patients at risk for AKI.

Drug-associated acute kidney injury: who's at risk?

The contribution of nephrotoxic medications to the development of acute kidney injury (AKI) is becoming better understood concomitant with the increased incidence of AKI in children. Treatment of AKI is not yet available, so prevention continues to be the most effective approach. There is an opportunity to mitigate severity and prevent the occurrence of AKI if children at increased risk are identified early and nephrotoxins are used judiciously. Early detection of AKI is limited by the dependence of nephrologists on serum creatinine as an indicator. Promising new biomarkers may offer early detection of AKI prior to the rise in serum creatinine. Early detection of evolving AKI is improving and offers opportunities for better management of nephrotoxins. However, the identification of patients at increased risk will remain an important first step, with a focus on the use of biomarker testing and interpretation of the results.

Acute kidney injury in Pediatric Intensive Care Unit: Incidence, risk factors, and outcome

Objective:

To determine incidence, risk factors, and outcome of acute kidney injury (AKI) in Pediatric Intensive Care Unit (PICU).

Materials and Methods:

This is a prospective, observational study conducted in PICU of Department of Paediatrics, S.P. Medical College, Bikaner, from October 2013 to May 2014. In this study, 536 patients of aged 29 days to 16 years were screened for AKI according to the Pediatric Risk, Injury, Failure, Loss, End-stage Renal Disease (pRIFLE) criteria. Their clinical and biochemical data were recorded and followed up to their discharge/death.

Results:

During the study period, 230 (42.9%) out of 536 patients developed AKI. Younger age (<5 years) and females (P ≤ 0.013) were more prone to develop AKI. Most common etiologies were septicemia, multiple organ dysfunction syndrome (MODS), gastroenteritis, and severe malaria (P ≤ 0.05). The maximal stage of AKI was stage “R” (49.1%), followed by “I” (29.5%) and “F” (21.3%). Major PICU-related risk factors were use of vasoactive drug (VD) and nephrotoxic drug (ND) and need of mechanical ventilation (MV) (P ≤ 0.05). Length of stay was significantly longer than non-AKI patients (P ≤ 0.05). Mortality in AKI (47.5%) was higher (P ≤ 0.05%) in comparison to non-AKI (25.56%).

Conclusion:

AKI is common in critically sick children, especially in younger age and in females with septicemia and MODS. Use of VD and ND and need of MV are common risk factors. AKI is associated with longer hospital stay and higher mortality. pRIFLE is better diagnostic criteria in early detection of AKI and reduction of their morbidity and mortality.

Serum cystatin is a useful marker for the diagnosis of acute kidney injury in critically ill children: prospective cohort study

Background

Acute kidney injury (AKI) has been associated with high morbidity and mortality rates among critically ill children. Cystatin C is a protease inhibitor, and studies have shown that it is a promising marker for the early diagnosis of AKI. Our goal in this study was to assess whether serum cystatin C could serve as an accurate marker for the diagnosis of AKI.

Methods

This prospective study was undertaken in the pediatric intensive care unit at King Abdulaziz University Hospital. Serum creatinine and serum cystatin C levels were both measured in patients on admission (0 h) and at 6, 12, and 24 h after admission. AKI was diagnosed according to the modified pRIFLE criteria. Receiver operating characteristic (ROC) curve analysis was performed to assess the utility of serum cystatin C for diagnosing AKI.

Results

A total of 62 patients were enrolled in this study, and 32 were diagnosed with AKI according to the modified pRIFLE criteria (51.4 %). The area under the ROC curve for serum cystatin indicated that it was a good marker for the diagnosis of AKI at 0, 6, 12 and 24 h, with sensitivities of 78, 94, 94 and 83 %, respectively. However, the specificities of serum cystatin C at 0, 6, 12, and 24 h were 57, 57, 60 and 50 %, respectively. The optimal cutoff value was 0.645 mg/L. The area under the ROC for serum creatinine showed sensitivities of 50, 65.4, 69.2 and 57.7 % and specificities of 67.7, 70, 60 and 70 % at 0, 6, 12 and 24 h, respectively. The optimal cutoff value for serum creatinine was 30 μmol/l. Comparisons of ROC curves revealed that serum cystatin C was superior to serum creatinine for the diagnosis of AKI at 12 h (p = 0.03), but no differences were detected at 0, 6 or 24 h.

Conclusion

Serum cystatin is a sensitive, but not a specific, marker for the diagnosis of AKI in critically ill children.

Clinical Pharmacology Studies in Critically Ill Children

Developmental and physiological changes in children contribute to variation in drug disposition with age. Additionally, critically ill children suffer from various life-threatening conditions that can lead to pathophysiological alterations that further affect pharmacokinetics (PK). Some factors that can alter PK in this patient population include variability in tissue distribution caused by protein binding changes and fluid shifts, altered drug elimination due to organ dysfunction, and use of medical interventions that can affect drug disposition (e.g., extracorporeal membrane oxygenation and continuous renal replacement therapy). Performing clinical studies in critically ill children is challenging because there is large inter-subject variability in the severity and time course of organ dysfunction; some critical illnesses are rare, which can affect subject enrollment; and critically ill children usually have multiple organ failure, necessitating careful selection of a study design. As a result, drug dosing in critically ill children is often based on extrapolations from adults or non-critically ill children. Dedicated clinical studies in critically ill children are urgently needed to identify optimal dosing of drugs in this vulnerable population. This review will summarize the effect of critical illness on pediatric PK, the challenges associated with performing studies in this vulnerable subpopulation, and the clinical PK studies performed to date for commonly used drugs.

Acute kidney injury after heart transplant in young children: risk factors and outcomes

BACKGROUND

Critical illness following heart transplantation can include acute kidney injury (AKI). Study objectives were to define the epidemiology of, risk factors for, or impact on outcomes of AKI after pediatric heart transplant.

METHODS

Using data from a prospective study of 66 young children, we evaluated: (1) post-operative AKI rate (by pediatric modified RIFLE criteria); (2) pre, intra, and early post-operative AKI risk factors using stepwise logistic regression (3) effect of AKI on short-term outcomes (ventilation and length of pediatric intensive care unit (PICU) stay) using stepwise multiple regression.

RESULTS

AKI occurred in 73 % of children. Pre-transplant ventilation and higher baseline estimated creatinine clearance (eCCl) were independent risk factors for AKI. Pre-operative inotrope use was associated with reduced risk of AKI. Tacrolimus level emerged as important in multivariable risk prediction. Children with AKI had a longer duration of ventilation and length of pediatric intensive care unit (PICU) stay, with AKI being an independent predictor.

CONCLUSIONS

AKI was common after heart transplant and associated with more complicated early post-transplant course. Lower baseline eCCl was associated with lower incidence of AKI; this merits further investigation. The association of pre-operative inotropes with less AKI may reflect a pathophysiological mechanism or be a surrogate for clinical factors and management prior to transplant. Avoiding high tacrolimus levels may be a modifiable risk factor for AKI.

Clinical characteristics and mortality risk prediction in children with acute kidney injury

Background:

Acute kidney injury (AKI) is characterized by a reversible increase in the blood concentration of creatinine and nitrogenous waste products and by the inability of the kidney to regulate fluid and electrolyte homeostasis appropriately.

Objective:

AKI is a serious condition in critically ill patients. The aim of the study was to determine incidence rate, identify risk factors, and describe the clinical outcome of AKI in the Pediatric Intensive Care Unit (PICU).

Materials and Methods:

This prospective observational study was conducted in the PICU of a hospital in the South-east Area of Iran (Zahedan City), to study the clinico-etiological profile of AKI (defined according to the AKI network criteria). Over a period of 20 months from April 2012 to December 2014, 303 children were included in the study. Both the groups of patients, those who developed AKI and those who did not develop AKI, were then followed during the course of their hospital stay.

Results:

There were 303 cases included in the study, with the incidence rate of AKI of 14.9% in PICU. The most common PICU admission diagnoses in AKI were neurologic 85 (%28.05), followed by heart diseases 52 (17.18%) and 31 (10.23%) for respiratory diseases. AKI was 43.5 and 5.4 times more prevalent in renal and endocrine patients compared to those with heart disease respectively. The mortality rate was estimated to be higher in patients with AKI compared to their counterparts (40% vs. 17.8%). Chance of death increased in patients with AKI (odds ratio = 3.04).

Conclusion:

AKI is a serious problem, but its true incidence is unknown. Understanding the epidemiology of AKI by using of standard definition help us to find high-risk children that are the first step to improve outcomes. The future multiple-center study may benefit by better identifying risk factors and early detection of AKI by using biomarkers novel to prevent the developing of AKI.

Umbilical neutrophil gelatinase-associated lipocalin level as an early predictor of acute kidney injury in neonates with hypoplastic left heart syndrome

Acute kidney injury (AKI) is a primarily described complication after unbalanced systemic perfusion in neonates with congenital heart defects, including hypoplastic left heart syndrome (HLHS). The aim of the study was to compare the umbilical NGAL concentrations between neonates born with HLHS and healthy infants, as well as to analyze whether the determination of NGAL level could predict AKI in neonates with prenatally diagnosed HLHS. Twenty-one neonates with prenatally diagnosed HLHS were enrolled as study group and 30 healthy neonates served as controls. Perinatal characteristics and postnatal parameters were extracted from the hospital neonatal database. In umbilical cord blood, we determined plasma NGAL concentrations, acid base balance, and lactate and creatinine levels. In neonates with HLHS, complications (respiratory insufficiency, circulatory failure, NEC, IVH, and AKI) were recorded until the day of cardiosurgery. We observed in neonates with HLHS higher umbilical NGAL levels compared to controls. Among 8 neonates with HLHS and diagnosed AKI stage 1, we observed elevated NGAL levels in comparison to those newborns without AKI. Umbilical NGAL could predict, with high sensitivity and specificity, AKI development in study neonates. We suggest that the umbilical blood NGAL concentration may be an early marker to predict AKI in neonates with HLHS.