Continuous Renal Replacement Therapy for Treatment of Severe Attacks of Inborn Errors of Metabolism

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.

Patient-centered outcomes in pediatric continuous kidney replacement therapy: new morbidity and worsened functional status in survivors

BACKGROUND

Ongoing measures to improve pediatric continuous kidney replacement therapy (CKRT) have lowered mortality rates, shifting the focus to survivor functional status. While septic acute kidney injury generates new morbidity in pediatric critically ill patients, acquired morbidities and functional status of CKRT population are unknown. We predicted that CKRT survivors are at risk for new morbidity and would have worse functional status at PICU discharge compared to baseline, and aimed to describe associated factors.

METHODS

Retrospective cohort study over 24 months of CKRT patients surviving to PICU discharge in a quaternary children's hospital. Functional outcome was determined by Functional Status Scale (FSS).

RESULTS

FSS scores were higher at PICU and hospital discharge compared to baseline. Of 45 CKRT survivors, 31 (69%) had worse FSS score at PICU discharge and 51% had new morbidity (≥3 increase in FSS); majority qualified as moderate to severe disability (FSS ≥10). Four patients (9%) had new tracheostomy, 3 (7%) were ventilator dependent, and 10 (22%) were dialysis dependent. Most (23/45, 51%) required outpatient rehabilitation. Cumulative days on sedation, controlled for illness severity, were independently associated with worse FSS at PICU discharge (aOR 25.18 (3.73, 169.92)). In adjusted analyses, duration of sedation was associated with new morbidity, while neurologic comorbidity, percent fluid overload at CKRT start, and nonrenal comorbidity were associated with moderate to severe disability at PICU discharge when controlled for baseline FSS.

CONCLUSIONS

CKRT survivors, with new morbidity and worse functional outcomes at PICU discharge, are a newly described vulnerable population requiring targeted follow-up. Deliberate decrease of sedation exposure in patients with decreased clearance due to organ dysfunction needs to be studied as a modifiable risk factor.

Characteristics of continuous venovenous hemodiafiltration in the acute treatment of inherited metabolic disorders

BACKGROUND

Continuous kidney replacement therapies (CKRT) have been reported to be an effective approach to removing toxic metabolites in inborn errors of metabolism (IEM). The present study evaluates efficiency and complications of CKRT in children with IEM.

METHODS

Patients diagnosed with IEM who underwent CKRT in pediatric and neonatal intensive care units were analyzed. CKRT were initiated in patients with persistently high blood ammonia levels (≥ 500 μmol/L), blood ammonia levels > 250 μmol/L in the presence of moderate encephalopathy, high blood leucine levels (≥ 1500 μmol/L), and blood leucine levels < 1500 μmol/L in the presence of deteriorating neurological status or persistent metabolic acidosis.

RESULTS

Of 22 patients enrolled, nine (40.9%) Maple syrup urine disease (MSUD), eight (36.4%) urea cycle disorders (UCD), and five (22.7%) organic acidemias (OA). Median age was 72.3 [9.9-1040.8] days. In total, 28 dialysis sessions were analyzed [16 (57.1%) continuous venovenous hemodialysis, and 12 (42.9%) continuous venovenous hemodiafiltration]. A significant decrease was noted in leucine levels (from 1608.4 ± 885.3 to 314.6 ± 109.9 µmol/L) of patients with MSUD, while ammonia levels were significantly decreased in patients with UCD and OA (from 1279.9 ± 612.1 to 85.1 ± 21.6 µmol/L). The most frequent complications of CKRT were thrombocytopenia (60.7%), hypotension (53.6%), and hypocalcemia (42.9%). Median age of patients with hypotension treated with vasoactive medications was significantly lower than median age of those with normal blood pressure.

CONCLUSION

CKRT is a reliable approach for effective and rapid removal of toxic metabolites in children with IEM, and CKRT modalities can be safely used and are well-tolerated in infants.

[Application of continuous renal replacement therapy in the treatment of neonates with inherited metabolic diseases]

OBJECTIVE

To study the efficacy and safety of continuous renal replacement therapy (CRRT) in the treatment of neonates with inherited metabolic diseases and hyperammonemia.

METHODS

A retrospective analysis was performed on the medical records of neonates with inherited metabolic diseases and hyperammonemia who were hospitalized and underwent CRRT in the Department of Neonatology, Hunan Children's Hospital, from September 2016 to March 2020, including general conditions, clinical indices, laboratory markers, and adverse reactions.

RESULTS

A total of 11 neonates were enrolled, with 7 boys (64%) and 4 girls (36%). The neonates had a mean gestational age of (38.9±0.8) weeks, a mean body weight of (3 091±266) g on admission, and an age of (5.7±2.0) days at the time of CRRT. The main clinical manifestations were vomiting (100%), convulsions (100%), and coma (55%), and the main primary disease was urea cycle disorder (55%). The mean duration of CRRT was (44±14) hours, the medium duration of coma before CRRT was 2 hours, and the total duration of coma was 10 hours. The patients had a mean hospital stay of (18±10) days and a survival rate of 73%, and 2 survivors had epilepsy. After treatment, all patients had significant reductions in blood ammonia, lactic acid, and K⁺ concentration (P < 0.001) and a significant increase in pH (P < 0.001). The incidence rate of adverse reactions was 27%.

CONCLUSIONS

CRRT is safe and effective in the treatment of neonates with inherited metabolic diseases and hyperammonemia.