Molecular Absorbent Recirculating System therapy (MARS®) in pediatric acute liver failure: a single center experience

Diagnosis and management of pediatric acute liver failure: consensus recommendations of the Indian Society of Pediatric Gastroenterology, Hepatology, and Nutrition (ISPGHAN)

Timely diagnosis and management of pediatric acute liver failure (PALF) is of paramount importance to improve survival. The Indian Society of Pediatric Gastroenterology, Hepatology, and Nutrition invited national and international experts to identify and review important management and research questions. These covered the definition, age appropriate stepwise workup for the etiology, non-invasive diagnosis and management of cerebral edema, prognostic scores, criteria for listing for liver transplantation (LT) and bridging therapies in PALF. Statements and recommendations based on evidences assessed using the modified Grading of Recommendations Assessment, Development and Evaluation (GRADE) system were developed, deliberated and critically reappraised by circulation. The final consensus recommendations along with relevant published background information are presented here. We expect that these recommendations would be followed by the pediatric and adult medical fraternity to improve the outcomes of PALF patients.

Molecular Adsorbent Recirculating System for Acute Liver Failure in a New Pediatric-Based Extracorporeal Liver Support Program

IMPORTANCE

Acute liver failure (ALF) carries significant morbidity and mortality, for both pediatric and adult patients. Albumin dialysis via the molecular adsorbent recirculating system (MARS) is a form of extracorporeal liver support (ELS) that can reduce hepatic encephalopathy (HE), a main driver of mortality in ALF. However, data on MARS and its benefit on mortality have been inconsistent.

OBJECTIVES

We sought to report our experiences and patient outcomes from the first 2 years of operation of a new ELS program, within an established pediatric liver transplantation center.

DESIGN SETTING AND PARTICIPANTS

Retrospective review of outcomes in pediatric and adult patients treated with MARS therapy for ALF, from 2021 to 2022.

MAIN OUTCOMES AND MEASURES

Outcomes included reduction in HE and biochemical markers of ALF after MARS therapy, survival, and transplant-free survival. Comparisons were made via Wilcoxon signed-rank test.

RESULTS

Five pediatric and two adult patients underwent MARS for ALF. Ages ranged from 2 to 29 years. Overall, 21 MARS runs were performed (median 3 runs per patient, 12.4 hr per run [interquartile range, IQR 10.1-17]). Overall survival was 85.7%, and transplant-free survival was 71.4%. There was a statistically significant reduction in HE score with MARS therapy (median 3 [IQR 3-4] to 1 [IQR 0-1], p = 0.03), and in ALF biomarkers including ammonia (256 µL/dL [195-265] to 75 µL/dL [58-101], p = 0.02), aspartate aminotransferase (6,362 U/L [920-8,305] to 212 U/L [72-431], p = 0.02), alanine aminotransferase (8,362 U/L [3,866-9,189] to 953 U/L [437-1,351], p = 0.02), and international normalized ratio (4.5 [3.3-6.7] to 1.3 [1.2-1.4], p = 0.02).

CONCLUSIONS AND RELEVANCE

MARS therapy for ALF was well tolerated by both pediatric and adult patients, and resulted in significant improvement in clinical and biochemical parameters. We demonstrated encouraging overall and transplant-free survival, suggesting that early initiation of MARS with relatively long and frequent cycle times may be of significant benefit to ALF patients, and is worthy of additional study in larger cohorts.

Combination of Plasma Exchange and Adsorption Versus Plasma Exchange in Pediatric Acute Liver Failure: A Multicenter Cohort Study

OBJECTIVES

This study aimed to compare the efficacy of double plasma molecular adsorption system (DPMAS) with half-dose plasma exchange (PE) to that of full-dose PE in pediatric acute liver failure (PALF).

METHODS

This multicenter, retrospective cohort study was conducted in 13 pediatric intensive care units in Shandong Province, China. DPMAS+PE and single PE therapies were performed in 28 and 50 cases, respectively. The patients' clinical information and biochemical data were obtained from the patients' medical records.

RESULTS

The severity of illness did not differ between the 2 groups. At 72 hours after treatment, comparing with PE group, the rates of decline of Pediatric model for End-stage Liver Disease and Pediatric Sequential Organ Failure Assessment scores as well as total bilirubin blood ammonia and interleukin-6 were significantly higher, while the short-term effective rate (75.0% vs 44.0%, P = 0.008) was significantly higher in the DPMAS+PE group. The volume of plasma consumption (26.5 vs 51.0 mL/kg, P = 0.000) and the rate of adverse events (3.6% vs 24.0%, P = 0.026) were lower in the DPMAS+PE group than in the PE group, respectively. However, there was no statistical difference in the 28-day mortality between the 2 groups (21.4% vs 40.0%, P > 0.05).

CONCLUSIONS

For PALF patients, both DPMAS + half-dose PE and full-dose PE could improve the liver function, while DPMAS + half-dose PE could significantly reduce plasma consumption without obvious adverse effects in contrast with full-dose PE. Thus, DPMAS + half-dose PE may be a suitable alternative method for PALF in the context of the increasingly tight blood supply situation.

Acute Fatty Liver of Pregnancy

Acute fatty liver of pregnancy is a rare, but potentially fatal obstetric disorder characterized principally by varying degrees of hepatic failure with an onset typically in late pregnancy. This review outlines the etiopathogenesis and describes the multiorgan involvement that often results in a number of clinical and laboratory aberrations. These laboratory derangements provide distinct features to differentiate from other obstetric complications, such as hemolysis, elevated liver enzymes, and low platelet count (HELLP) syndrome. Once recognized, central to the management of acute fatty liver of pregnancy is delivery planning and meticulous supportive care. One particularly dangerous complication is profound coagulopathy. After delivery, the coagulation defect resolves over 1-2 days, and hepatic and renal function are restored soon thereafter. This report offers anticipated recovery and management strategies for commonly associated complications. Application of these factors has served to decrease mortality from as high as 80% down to 10%; however, given the seriousness of this condition, severe maternal morbidities are frequently associated with this obstetric emergency.

Artificial liver support systems

Artificial liver systems are used to bridge between transplantation or to allow a patient's liver to recover. They are used in patients with acute liver failure (ALF) and acute-on-chronic liver failure. There are five artificial systems currently in use: molecular adsorbent recirculating system (MARS), single-pass albumin dialysis (SPAD), Prometheus, selective plasma filtration therapy, and hemodiafiltration. The aim is to compare existing data on the efficiency of these devices. A literature search was conducted using online libraries. Inclusion criteria included randomized control trials or comparative human studies published after the year 2000. A systematic review was conducted for the five individual devices with a more detailed comparison of the biochemistry for the SPAD and MARS systems. Eighty-nine patients were involved in the review comparing SPAD and MARS. Results showed that there was an average reduction in bilirubin (-53 μmol/L in MARS and -50 μmol/L in SPAD), creatinine (-19.5 μmol/L in MARS and -7.5 μmol/L in SPAD), urea (-0.9 mmol/L in MARS and -0.75 mmol/L in SPAD), and gamma-glutamyl transferase (-0.215 μmol/L·s in MARS and -0.295 μmol/L·s in SPAD) in both SPAD and MARS. However, there was no significant difference between the changes in the two systems. This review demonstrated that both MARS and SPAD aid recovery of ALF. There is no difference between the efficiency of MARS and SPAD. Because of the limited data, there is a need for more randomized control trials. Evaluating cost and patient preference would aid in differentiating the systems.

Application of the Molecular Adsorbent Recirculating System in Type 1 Hepatorenal Syndrome in the Course of Alcohol-Related Acute on Chronic Liver Failure

BACKGROUND This study aimed to evaluate the Molecular Adsorbent Recirculating System (MARS) effectiveness in patients with alcohol-related acute-on-chronic liver failure (AoCLF) complicated with type 1 hepatorenal syndrome (HRS). So far, MARS efficacy and safety has been demonstrated in various acute liver failure scenarios. MATERIAL AND METHODS Data from 41 MARS procedures (10 patients with type 1 HRS, in the course of alcohol-related AoCLF were considered for this study. Biochemical tests of blood serum were performed before and after each procedure. The condition of patients was determined before and after the treatment with the use of the model for end-stage liver disease - sodium (MELD-Na) and the stage of encephalopathy severity based on the West Haven criteria. RESULTS During the observation period (20.5±13.9 days), 5 patients died, and the remaining 5 surviving patients were discharged from the hospital. In the group of 10, the 14-day survival, starting from the first MARS treatment, was 90%. The MARS procedure was associated with a 19% reduction in bilirubin (27.5±6.1 versus 22.3±4.0 mg/dL, P<0.001), 37% reduction in ammonia (44.1±22.5 versus 27.6±20.9 P<0.001), 27% reduction in creatinine (1.5±1.0 versus 1.1±0.6 mg/dL, P<0.001) and 14% reduction urea (83.8±36.1 versus 72.1±33.3, P<0.001) in blood serum samples, with stable hemodynamic parameters. In the group of patients discharged from the clinic (n=5), the MARS treatments resulted in an improvement in hepatic encephalopathy (West Haven; P=0.043), as well as a reduction in the MELD-Na score (P=0.015). CONCLUSIONS MARS is a hemodynamically safe method for supporting the function of the liver and the kidneys. Application of the MARS reduces the symptoms of encephalopathy in patients with alcohol-related type 1 HRS.

Prognostic parameters of pediatric acute liver failure and the role of plasma exchange

BACKGROUND

This study investigated the prognostic parameters and beneficial effects of repeat plasma exchange in children with acute liver failure (ALF).

METHODS

Twenty-three patients under 18 years of age admitted to National Taiwan University Hospital due to ALF from 2003 to 2016 were included in this retrospective analysis.

RESULTS

Among the patients, 11 (48%) had native liver recovery (NLR), 9 (39.1%) died without liver transplant, and 3 (12.9%) received liver transplantation. The NLR group showed a lower proportion of idiopathic cases, lower peak ammonia level, higher peak alpha fetoprotein (AFP) level, and they had plasma exchange fewer times than the other groups. Receiver operating characteristic curve analyses yielded optimal cutoff values of plasma exchange (≤6 times), peak ammonia level (<190 μmol/L), and peak AFP level for predicting NLR in children with ALF.

CONCLUSION

Pediatric ALF with idiopathic etiology, high peak ammonia level, and low peak AFP level are associated with fewer cases of NLR. Plasma exchange for more than six times probably offers little benefit with regard to patient survival if liver transplantation is not performed promptly.

A successful use of therapeutic plasma exchange in a fulminant form of acute fatty liver of pregnancy

Acute fatty liver of pregnancy (AFLP) continues to raise special concerns since its first post-mortem description by Sheehan in 1940. While early diagnosis and expedite delivery are the cornerstone of management, this condition remains fatal for both mother and fetus. Acute fulminant liver failure is the most serious and life-threatening AFLP-related complication and can require liver transplant despite aggressive supportive management. In lieu of transplant, therapeutic plasma exchange (PE) has emerged as a life-saving alternative and has, in few reports, demonstrated efficacy for the reversal of this dangerous condition. Here we present a case report of a patient diagnosed with fulminant liver failure complicating an AFLP and progressed to severe hepatic encephalopathy who was successfully treated with five rounds of plasma exchange.

Hybrid Extracorporeal Therapies as a Bridge to Pediatric Liver Transplantation

OBJECTIVES

Standard intensive care treatment is inadequate to keep children with liver failure alive without catastrophic complications to ensure successful transplant, as accumulation of endogenous protein-bound toxins often lead to hepatic encephalopathy, hepatorenal syndrome, cardiovascular instability, and multiple organ failure. Given paucity of proven treatment modalities for liver failure, blood purification using different extracorporeal treatments as a bridge to transplantation is used, but studies evaluating the safety and efficacy of combination of these therapies, especially in pediatric liver failure, are lacking. We describe our experience at a major tertiary children's hospital, where a unique hybrid extracorporeal treatment protocol has been instituted and followed for acute liver failure or acute-on-chronic liver failure as a bridge to transplantation. This protocol combines high-flux continuous renal replacement therapy for hyperammonemia, therapeutic plasma exchange for coagulopathy, and albumin-assisted dialysis (molecular adsorbent recirculating system) for hepatic encephalopathy.

DESIGN

Retrospective observational study.

SETTING

Freestanding tertiary children's hospital and liver transplant referral center.

PATIENTS

All patients with acute liver failure/acute-on-chronic liver failure receiving hybrid extracorporeal therapy over 24 months.

INTERVENTION

Hybdrid extracorporeal therapy.

MEASUREMENTS AND MAIN RESULTS

Fifteen children (age 3 yr [0.7-9 yr]; 73% male) with acute liver failure/acute-on-chronic liver failure who were either listed or actively considered for listing and met our protocol criteria were treated with hybrid extracorporeal therapy; 93% were ventilated, and 80% were on vasoactive support. Of these, two patients recovered spontaneously, four died prior to transplant, and nine were successfully transplanted; 90-day survival post orthotopic liver transplant was 100%. Overall survival to hospital discharge was 73%.

CONCLUSIONS

Hybrid extracorporeal therapies can be effectively implemented in pediatric liver failure as a bridge to transplantation. Overall complexity and heavy resource utilization need to be carefully considered in instituting these therapies in suitable candidates.

Acute Liver Failure: Outcome and Value of Pediatric End-Stage Liver Disease Score in Pediatric Cases

PURPOSE

The aims of this study were to analyze the characteristics of patients with acute liver failure (ALF) in our center and evaluate the prognostic value of the Pediatric End-Stage Liver Disease (PELD) score calculated at admission.

METHODS

A retrospective analysis of patients with ALF younger than 15 years between 2005 and 2013 was performed. Information collected included age, sex, etiology of ALF, laboratory tests, PELD score, stage of encephalopathy, and need for liver support devices such as MARS and/or liver transplant (LT) and survival. A poor prognosis was defined as the need for LT or death.

RESULTS

Twenty patients (10 male patients, 50%) with a median age of 2.6 years (3 days-14.5 y old) were included. Acute liver failure was of indeterminate cause in 5 cases (25%). Within the recognized causes, the most frequent were viral hepatitis (herpes simplex virus, adenovirus, influenza B, Epstein-Barr virus), autoimmune hepatitis, and metabolopathies. Sixty percent presented with encephalopathy at diagnosis. Four patients were aided by a MARS liver support device. Six patients received a total of 7 transplants, all from deceased donors. The rate of spontaneous recovery was 45%. Currently 13 patients (65%) are living, 4 of them with an LT. Six patients died because of ALF. The mean PELD score of patients with spontaneous recovery was 15.31 (5.3-27.6) compared with a mean of 29.5 (17.2-39.4) in LT patients and 31.55 (15.8-52.4) for nonsurvivors (P = 0.013).

CONCLUSIONS

High PELD scores at diagnosis were accurate predictors of a poor prognosis in our patients with ALF. This model may help in the clinical management of this entity, although prospective validation is needed.

Extracorporeal Liver Support Systems in Paediatric Liver Failure

Extracorporeal liver support systems (ELSS), encompassing artificial and bioartificial devices, have been used for decades, with the aim of supporting patients with acute liver failure and acute-on chronic liver failure, as a bridge to recovery (acute liver failure only) or liver transplantation, in an era of organ donation shortage. Although biochemical efficacy has been consistently demonstrated by these devices, translation into clinical and survival benefits has been unclear, due to study limitations and lack of reliable prognostic scoring in liver failure. Consequently, extracorporeal devices are not widely accepted as routine therapy in adult liver failure. Recent large multicentre trials using artificial liver systems have not revealed beneficial outcomes associated with albumin dialysis but plasma exchange practices have shown some potential. In paediatric liver failure, data on extracorporeal systems is scarce, comprising few reports on albumin dialysis (namely, Molecular Adsorbent Recirculating System; MARS) and plasma exchange. When extrapolating data from adult studies differences in disease presentation, aetiology, prognosis and the suitability, and safety of such devices in children must be considered. The aim of this review is to critically appraise current practices of extracorporeal liver support systems to help determine efficacy in paediatric liver failure.

Metabolic Liver Diseases Presenting as Acute Liver Failure in Children

CONTEXT

Suspecting metabolic liver disease in an infant or young child with acute liver failure, and a protocol-based workup for diagnosis is the need of the hour.

EVIDENCE ACQUISITION

Data over the last 15 years was searched through Pubmed using the keywords Metabolic liver disease and Acute liver failure with emphasis on Indian perspective. Those published in English language where full text was retrievable were included for this review.

RESULTS

Metabolic liver diseases account for 13-43% cases of acute liver failure in infants and young children. Etiology remains indeterminate in very few cases of liver failure in studies where metabolic liver diseases were recognized in large proportion. Galactosemia, tyrosinemia and mitochondrial disorders in young children and Wilsons disease in older children are commonly implicated. A high index of suspicion for metabolic liver diseases should be kept when there is strong family history of consanguinity, recurrent abortions or sibling deaths; and history of recurrent diarrhea, vomiting, failure to thrive or developmental delay. Simple dietary modifications and/or specific management can be life-saving if instituted promptly.

CONCLUSION

A high index of suspicion in presence of red flag symptoms and signs, and a protocol-based approach helps in timely diagnosis and prompt administration of lifesaving therapy.

Efficacy of coupled low-volume plasma exchange with plasma filtration adsorption in treating pigs with acute liver failure: A randomised study

BACKGROUND & AIMS

Extracorporeal blood purification systems for supportive therapy of liver failure are widely used. We developed a novel blood purification system, named Li's artificial liver system (Li-ALS), which couples low-volume plasma exchange (low-volume PE) with plasma filtration adsorption (PFA). This study aims to evaluate the efficacy of our novel system in pigs with acute liver failure (ALF).

METHODS

Thirty-two pigs were infused with D-galactosamine (1.3g/kg) to induce ALF. All animals were equally and randomly divided into four groups: the ALF control group received intensive care, the PFA group underwent five hour plasma recycling filtration and adsorption purification, the low-volume PE group received one hour low-volume PE, and the Li-ALS group underwent one hour low-volume PE, followed by five hour PFA. Intervention was initiated 36hours after drug administration. The efficacy of each treatment was assessed by survival time and improvement in hematological, biochemical, and immunohistological parameters.

RESULTS

Pigs in the Li-ALS group survived longer than those in the other groups (p<0.001, ALF control: 60±2h; PFA group: 74±2h; low-volume PE group: 75±2h; and Li-ALS group: 90±3h). Liver enzyme, bilirubin, bile acid and blood ammonia levels were decreased significantly after Li-ALS treatment, and increases in inflammatory cytokines were ameliorated. A higher hepatocyte regeneration index was also observed in the Li-ALS group.

CONCLUSION

Our novel Li-ALS could expedite liver regeneration and improve survival time; hence, it could be promising for treating ALF.