The impact of continuous renal replacement therapy for metabolic disorders in infants

Inborn errors of metabolism in neonates and pediatrics on varying dialysis modalities: a systematic review and meta-analysis

BACKGROUND

Some inborn errors of metabolism (IEMs) resulting in aberrations to blood leucine and ammonia levels are commonly treated with kidney replacement therapy (KRT). Children with IEMs require prompt treatment, as delayed treatment results in increased neurological and developmental morbidity.

OBJECTIVES

Our systematic review in neonates and pediatrics evaluates survival rates and reductions in ammonia and leucine levels across different KRT modalities (continuous KRT (CKRT), hemodialysis (HD), peritoneal dialysis (PD)).

DATA SOURCES

A literature search was conducted through PubMed, Web of Science, and Embase databases for articles including survival rate and toxic metabolite clearance data in pediatric patients with IEM undergoing KRT.

STUDY ELIGIBILITY CRITERIA

Cross-sectional, prospective, and retrospective studies with survival rates reported in patients with IEM with an intervention of CKRT, PD, or HD were included. Studies with patients receiving unclear or multiple KRT modalities were excluded.

STUDY APPRAISAL AND SYNTHESIS METHODS

Analysis variables included efficacy outcomes [% reduction in ammonia (RIA) from pre- to post-dialysis and time to 50% RIA] and mortality. The Newcastle Ottawa Risk of Bias quality assessment was used to assess bias. All statistical analyses were performed with MedCalc Statistical Software version 19.2.6.

RESULTS

A total of 37 studies (n = 642) were included. The pooled proportion (95% CI) of mortality on CKRT was 24.84% (20.93-29.08), PD was 34.42% (26.24-43.33), and HD 34.14% (24.19-45.23). A lower trend of pooled (95% CI) time to 50% RIA was observed with CKRT [6.5 (5.1-7.8)] vs. PD [14.4 (13.3-15.5)]. A higher mortality was observed with greater plasma ammonia level before CKRT (31.94% for ≥ 1000 µmol/L vs. 15.04% for < 1000 µmol/L).

CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS

Despite the limitations in sample size, trends emerged suggesting that CKRT may be associated with lower mortality rates compared to HD or PD, with potential benefits including prevention of rebound hyperammonemia and improved hemodynamic control. While HD showed a trend towards faster achievement of 50% RIA, all modalities demonstrated comparable efficacy in reducing ammonia and leucine levels.

PROSPERO REGISTRATION

CRD42023418842.

Extracorporeal pediatric renal replacement therapy: diversifying application beyond kidney failure

The utilization of extracorporeal renal replacement therapy (RRT), including continuous renal replacement therapy (CRRT) and hemodialysis (HD), beyond the treatment of volume overload and acute kidney injury (AKI) has witnessed a significant shift, demonstrating the potential to improve patient outcomes for a range of diseases. This comprehensive review explores the non-kidney applications for RRT platforms in critically ill children, focusing on diverse clinical scenarios such as sepsis, inborn errors of metabolism, liver failure, drug overdose, tumor lysis syndrome, and rhabdomyolysis. In the context of sepsis and septic shock, RRT not only facilitates fluid, electrolyte, and acid/base homeostasis, but may offer benefits in cytokine regulation, endotoxin clearance, and immunomodulation which may improve multi-organ dysfunction as well as hemodynamic challenges posed by this life-threatening condition. RRT modalities also have an important role in caring for children with inborn errors of metabolism, liver failure, and tumor lysis syndrome as they can control metabolic derangements with the efficient clearance of endogenous toxins in affected children. In cases of drug overdose, RRT is a crucial tool for rapid extracorporeal clearance of exogenous toxins, mitigating potential organ damage. The intricate interplay between liver failure and kidney function is examined, elucidating the role of RRT and plasma exchange in maintaining fluid and electrolyte balance when hepatic dysfunction complicates the clinical picture. Furthermore, RRT and HD are explored in the context of rhabdomyolysis, highlighting their utility in addressing AKI secondary to traumatic events and crush syndrome.

The Efficacy and Outcomes of Renal Replacement Therapy in Pediatric Metabolic Disorders

Background/Objectives: This study aims to evaluate the efficacy and outcomes of renal replacement therapy (RRT) in pediatric patients with metabolic diseases, specifically focusing on the impact of hemodialysis (HD) and peritoneal dialysis (PD) on clinical parameters, toxin reduction, and long-term survival. Methods: This retrospective study included 10 pediatric patients (eight females and two males) treated at a pediatric nephrology department between 2020 and 2023. Patients diagnosed with metabolic disorders, including maple syrup urine disease (MSUD), methylmalonic acidemia (MMA), and glycogen storage disease (GSD), underwent RRT. Clinical data, demographic information, and biochemical parameters were collected and analyzed. Results: Among the patients, 50% were diagnosed with MSUD, 30% with MMA, and 20% with GSD. RRT, including HD and PD, was administered to manage acute metabolic crises. HD was particularly effective in rapidly reducing toxic metabolite levels. Patients treated with HD showed significant reductions in leucine and ammonium levels, with median reductions of 94.5% and 86%, respectively. Overall, 60% of the patients demonstrated long-term survival, highlighting the critical role of RRT in managing metabolic crises. In conclusion, RRT, including HD and PD, is crucial in managing pediatric metabolic disorders by effectively reducing toxic metabolite levels and improving clinical outcomes. Conclusions: The results of this study are consistent with previous research, highlighting the critical role of RRT in the acute management of metabolic crises and supporting its adoption as a standard treatment method.

Changes in branched-chain amino acids in an infant with maple syrup urine disease during perioperative pediatric liver transplant: A case report

An 11-month-old female infant diagnosed with classic subtype IB maple syrup urine disease underwent living donor liver transplantation. Blood samples for plasma amino acid analysis were collected during the three phases of the operation. Despite the perioperative prophylactic administration of 12.5% hypertonic dextrose solution with insulin and a 20% intralipid emulsion, the blood levels of the branched-chain amino acids increased dramatically during surgery, consistent with an acute intraoperative metabolic decompensation. However, these blood levels normalized soon after liver transplantation with an excellent outcome. We suggest that the occurrence of an intraoperative metabolic crisis during liver transplantation is not necessarily a sign of graft failure.

Nutrition in critically ill children with acute kidney injury on continuous kidney replacement therapy: a 2023 executive summary

OBJECTIVES

Nutrition plays a vital role in the outcome of critical illness in children, particularly those with acute kidney injury. Currently, there are no established guidelines for children with acute kidney injury treated with continuous kidney replacement therapy. Our objective was to create clinical practice points for nutritional assessment and management in critically ill children with acute kidney injury receiving continuous kidney replacement therapy.

METHODS

An electronic search using PubMed and an inclusive academic library search (including MEDLINE, Cochrane, and Embase databases) was conducted to find relevant English-language articles on nutrition therapy for children (<18 y of age) receiving continuous kidney replacement therapy.

RESULTS

The existing literature was reviewed by our work group, comprising pediatric nephrologists and experts in nutrition. The modified Delphi method was then used to develop a total of 45 clinical practice points. The best methods for nutritional assessment are discussed. Indirect calorimetry is the most reliable method of predicting resting energy expenditure in children on continuous kidney replacement therapy. Schofield equations can be used when indirect calorimetry is not available. The non-intentional calories contributed by continuous kidney replacement therapy should also be accounted for during caloric dosing. Protein supplementation should be increased to account for the proteins, peptides, and amino acids lost with continuous kidney replacement therapy.

CONCLUSIONS

Clinical practice points are provided on nutrition assessment, determining energy needs, and nutrient intake in children with acute kidney injury and on continuous kidney replacement therapy based on the existing literature and expert opinions of a multidisciplinary panel.

Nutrition in Critically Ill Children with AKI on Continuous RRT: Consensus Recommendations

BACKGROUND

Nutrition plays a vital role in the outcome of critically ill children, particularly those with AKI. Currently, there are no established guidelines for children with AKI treated with continuous RRT (CRRT). A thorough understanding of the metabolic changes and nutritional challenges in AKI and CRRT is required. Our objective was to create clinical practice points for nutritional assessment and management in critically ill children with AKI receiving CRRT.

METHODS

PubMed, MEDLINE, Cochrane, and Embase databases were searched for articles related to the topic. Expertise of the authors and a consensus of the workgroup were additional sources of data in the article. Available articles on nutrition therapy in pediatric patients receiving CRRT through January 2023.

RESULTS

On the basis of the literature review, the current evidence base was examined by a panel of experts in pediatric nephrology and nutrition. The panel used the literature review as well as their expertise to formulate clinical practice points. The modified Delphi method was used to identify and refine clinical practice points.

CONCLUSIONS

Forty-four clinical practice points are provided on nutrition assessment, determining energy needs, and nutrient intake in children with AKI and on CRRT on the basis of the existing literature and expert opinions of a multidisciplinary panel.

Clinical characteristics and outcomes of continuous renal replacement therapy performed on younger children weighing up to 10 kg

BACKGROUND

This study aimed to investigate the clinical features, modality, complications, and effecting factors on the survival of children weighing up to 10 kg who received continuous renal replacement therapy (CRRT).

METHODS

This study was a retrospective observational study conducted in five pediatric intensive care units in tertiary hospitals in Turkey between January 2015 and December 2019.

RESULTS

One hundred and forty-one children who underwent CRRT were enrolled in the study. The median age was 6 (range, 2-12)months, and 74 (52.5%) were male. The median weight of the patients was 6 (range, 4-8.35) kg and 52 (36.9%) weighed less than 5 kg. The most common indication for CRRT was fluid overload in 75 (53.2%) patients, and sepsis together with multiorgan failure in 62 (44%). The overall mortality was 48.2%.

DISCUSSION

Despite its complexity, CRRT in children weighing less than 10 kg is a beneficial, lifesaving extracorporeal treatment modality.

Maple syrup urine disease decompensation misdiagnosed as a psychotic event

Maple syrup urine disease (MSUD) is an autosomal recessive metabolic disease resulting in impaired or absent breakdown of branched-chain amino acids (BCAA) valine, isoleucine, and leucine. Classic MSUD often presents in post-natal periods, at times before newborn screening results, and is treated with a protein restricted diet supplemented with medical food and close follow up to prevent toxic buildup of blood leucine.

Acute episodes of decompensation are prevented by early recognition and treatment. Acute episodes of metabolic decompensation in patients with MSUD are medical emergencies that require immediate treatments as cerebral edema may lead to brain-stem compression resulting in death. As the early outcomes improve for MSUD patients, the long-term sequelae of chronic hyperleucemia are being elucidated and include cognitive impairment, mental health disorders, and movement disorders.

In this report we present an adult patient with MSUD with attention deficit, hyperactivity type (ADHD) and depression due to prolonged exposure to elevated leucine managed with community support services who presented to the emergency department with new onset of acute hallucinations. He was held in the emergency department awaiting involuntary commitment to a psychiatric facility and underwent psychiatric treatments for suspected new onset hallucinations without improvement. Upon notification of metabolic specialists and initiation of appropriate therapy of MSUD, his leucine level normalized rapidly with resolution of his acute psychosis.

This case describes the acute presentation of psychosis in the setting of long-term toxicity of leucine. This case also highlights the importance of transition of care, education and planning in patients with inborn errors of metabolism.

Kidney support therapy in the pediatric patient: Unique considerations for a unique population

The use of kidney support therapy (KST) for use in managing patients with acute kidney injury (AKI) has expanded greatly in the last several decades. The growing use of KST modalities in children, and now in neonates, has been associated with opportunities for education, clinical research, clinical practice improvements, and outcomes research. A multitude of controversies exist in the field of pediatric KST-many of which are shared by adult critical care nephrology practice. Simultaneously, pediatric KST has led the way to a burgeoning exploration of the importance of fluid overload as it relates to KST initiation and management and also with quality improvement. In this review, we will explore and describe the paradigms contained with pediatric KST used to support children with AKI. In addition to the governing principles related to the mechanics of KST, we will describe the novel aspects of newer support machines and ethical considerations of KST provision. Anticoagulation, dose, and modality will be discussed as well as priming procedures for special considerations. The utilization of KST across pediatric populations represents the next frontier of critical care nephrology.

Renal Replacement Therapy in Neonates

Acute kidney injury (AKI) is a highly prevalent disease entity in the NICU, affecting nearly one-quarter of critically ill neonates by some reports. Though medical management remains the mainstay in the treatment of AKI, renal replacement therapy (RRT) is indicated when conservative measures are unable to maintain electrolytes, fluid balance, toxins, or waste products within a safe margin. Several modalities of RRT exist for use in neonatal populations, including peritoneal dialysis, hemodialysis, and continuous RRT. It is the aim of this review to introduce each of these RRT modalities, as well as to discuss their technical considerations, benefits, indications, contraindications, and complications.

Continuous renal replacement therapy and its impact on hyperammonaemia in acute liver failure

OBJECTIVE

Hyperammonaemia contributes to complications in acute liver failure (ALF) and may be treated with continuous renal replacement therapy (CRRT), but current practice is poorly understood.

DESIGN

We retrospectively analysed data for baseline characteristics, ammonia concentration, CRRT use, and outcomes in a cohort of Australian and New Zealand patients with ALF.

SETTING

All liver transplant ICUs across Australia and New Zealand.

PARTICIPANTS

Sixty-two patients with ALF.

MAIN OUTCOME MEASURES

Impact of CRRT on hyperammonaemia and patient outcomes.

RESULTS

We studied 62 patients with ALF. The median initial (first 24 h) peak ammonia was 132 μmol/L (interquartile range [IQR], 91-172), median creatinine was 165 μmol/L (IQR, 92-263) and median urea was 6.9 mmol/L (IQR, 3.1-12.0). Most patients (43/62, 69%) received CRRT within a median of 6 hours (IQR, 2-12) of ICU admission. At CRRT commencement, three-quarters of such patients did not have Stage 3 acute kidney injury (AKI): ten patients (23%) had no KDIGO creatinine criteria for AKI, 12 (28%) only had Stage 1, and ten patients (23%) had Stage 2 AKI. Compared with non-CRRT patients, those treated with CRRT had higher ammonia concentrations (median, 141 μmol/L [IQR, 102-198] v 91 μmol/L [IQR, 54-115]; P = 0.02), but a nadir Day 1 pH of only 7.25 (standard deviation, 0.16). Prevention of extreme hyperammonaemia (> 140 μmol/L) after Day 1 was achieved in 36 of CRRT-treated patients (84%) and was associated with transplant-free survival (55% v 13%; P = 0.05).

CONCLUSION

In Australian and New Zealand patients with ALF, CRRT is typically started early, before Stage 3 AKI or severe acidaemia, and in the presence hyperammonaemia. In these more severely ill patients, CRRT use was associated with prevention of extreme hyperammonaemia, which in turn, was associated with increased transplant-free survival.

Consensus guidelines for management of hyperammonaemia in paediatric patients receiving continuous kidney replacement therapy

Hyperammonaemia in children can lead to grave consequences in the form of cerebral oedema, severe neurological impairment and even death. In infants and children, common causes of hyperammonaemia include urea cycle disorders or organic acidaemias. Few studies have assessed the role of extracorporeal therapies in the management of hyperammonaemia in neonates and children. Moreover, consensus guidelines are lacking for the use of non-kidney replacement therapy (NKRT) and kidney replacement therapies (KRTs, including peritoneal dialysis, continuous KRT, haemodialysis and hybrid therapy) to manage hyperammonaemia in neonates and children. Prompt treatment with KRT and/or NKRT, the choice of which depends on the ammonia concentrations and presenting symptoms of the patient, is crucial. This expert Consensus Statement presents recommendations for the management of hyperammonaemia requiring KRT in paediatric populations. Additional studies are required to strengthen these recommendations.

This expert Consensus Statement from the Pediatric Continuous Renal Replacement Therapy (PCRRT) workgroup presents recommendations for the management of hyperammonaemia requiring kidney replacement therapy in paediatric populations. Additional studies are needed to strengthen these recommendations, which will be reviewed every 2 years.

Continuous Renal Replacement Therapy with High Flow Rate Can Effectively, Safely, and Quickly Reduce Plasma Ammonia and Leucine Levels in Children

Introduction: Peritoneal dialysis and continuous renal replacement therapy (CRRT) are the most frequently used treatment modalities for acute kidney injury. CRRT is currently being used for the treatment of several non-renal indications, such as congenital metabolic diseases. CRRT can efficiently remove toxic metabolites and reverse the neurological symptoms quickly. However, there is not enough data for CRRT in children with metabolic diseases. Therefore, we aimed a retrospective study to describe the use of CRRT in metabolic diseases and its associated efficacy, complications, and outcomes. Materials and Methods: We performed a retrospective analysis of the records of all patients admitted in the pediatric intensive care unit (PICU) for CRRT treatment. Results: Between December 2014 and November 2018, 97 patients were eligible for the present study. The age distribution was between 2 days and 17 years, with a mean of 3.77 ± 4.71 years. There were 13 (36.1%) newborn with metabolic diseases. The patients were divided into two groups: CRRT for metabolic diseases and others. There was a significant relationship between the groups, including age (p ≤ 0.001), weight (p = 0.028), blood flow rate (p ≤ 0.001); dialysate rate (p ≤ 0.001), and replacement rate (p ≤ 0.001). The leucine reduction rate was 3.88 ± 3.65 (% per hour). The ammonia reduction rate was 4.94 ± 5.05 in the urea cycle disorder group and 5.02 ± 4.54 in the organic acidemia group. The overall survival rate was 88.9% in metabolic diseases with CRRT. Conclusion: In particularly hemodynamically unstable patients, CRRT can effectively and quickly reduce plasma ammonia and leucine.