# Molecular adsorbent recirculating system (MARS®) and continuous renal replacement therapy for the treatment of paediatric acute liver failure — two-centre retrospective cohort study

## TL;DR

This study compares two treatments for children with severe liver failure and finds no significant difference in survival outcomes.

## Contribution

A two-center retrospective comparison of MARS® and CRRT in pediatric acute liver failure with no observed survival difference.

## Key findings

- No significant difference in survival with native liver or overall survival between MARS® and CRRT groups.
- CRRT patients were generally sicker at admission but had similar outcomes after treatment.
- Few studies have previously compared different extracorporeal therapies in pediatric acute liver failure.

## Abstract

To describe outcomes of a cohort of patients with paediatric acute liver failure (PALF) treated with either one of two extracorporeal therapies (ECT) — continuous renal replacement therapy (CRRT) and molecular adsorbent recirculatory system (MARS®). Retrospective, observational, cohort study at two European paediatric intensive care units (PICUs) — UK (2006–2017, CRRT) and the Netherlands (2003–2017, MARS® and CRRT). Patients were children (0–18 years) admitted to the PICU with PALF who required CRRT or MARS®. Between each group, we compared baseline characteristics, biochemical parameters at 0 and 24 h after commencing MARS®/CRRT, and clinical outcomes. In total, 95 patients (23 MARS®, 72 CRRT) were included. The median age at admission for the whole cohort was 4.3 years (interquartile range (IQR) 1.0–12.1), and 47/95 (49.5%) of patients had an indeterminate aetiology. A lower proportion of patients in the MARS® group were on inotropes or were ventilated at admission, and they had a lower Pediatric Index of Mortality 3 risk % than the CRRT group (14.5% (7.5–22) vs 20.4% (16.8–26.4), p = 0.002). After treatment, there were no significant differences detected between groups in survival with native liver, or overall survival (15/23 (65.2%) for MARS® and 49/72 (68.1%) for CRRT, p = 0.998). Conclusion: We did not detect a significant difference in clinical outcomes between PALF patients treated with CRRT or MARS®, despite a relatively sicker cohort in the CRRT group. Further high-quality evidence is necessary regarding the role of extracorporeal therapies in PALF, with consideration of clinical outcomes, feasibility, and cost.
What is Known:• Outcomes for children with paediatric acute liver failure (PALF) have improved in recent years secondary to improved supportive care aimed at avoiding liver transplantation.• Extracorporeal therapies, in particular continuous renal replacement therapy (CRRT), are increasingly applied in the management of these children; however few studies have compared outcomes between different extracorporeal therapies.What is New:• In this retrospective study across two centres, outcomes between patients with PALF treated with CRRT were compared to patients treated with MARS®.• There was no significant difference in key clinical outcomes between groups, including survival with native liver and overall survival.

What is Known:

• Outcomes for children with paediatric acute liver failure (PALF) have improved in recent years secondary to improved supportive care aimed at avoiding liver transplantation.

• Extracorporeal therapies, in particular continuous renal replacement therapy (CRRT), are increasingly applied in the management of these children; however few studies have compared outcomes between different extracorporeal therapies.

What is New:

• In this retrospective study across two centres, outcomes between patients with PALF treated with CRRT were compared to patients treated with MARS®.

• There was no significant difference in key clinical outcomes between groups, including survival with native liver and overall survival.

The online version contains supplementary material available at 10.1007/s00431-025-06013-y.