Delayed encephalopathy in fulminant hepatic failure in the pediatric population and the role of liver transplantation

Pediatric acute liver failure in Saudi Arabia: prognostic indicators, outcomes and the role of genetic testing

OBJECTIVE

The objective of this study was to determine the etiologies, outcomes, prognostic indicators and the role of genetic testing in children with acute liver failure (ALF).

METHODS

This retrospective study included 46 patients with pediatric acute liver failure (PALF) according to the PALF study group definition, admitted to King Fahad Specialist Hospital-Dammam, Saudi Arabia, between January 2014 and December 2021. Patients who survived with supportive therapy were designated as the recovery group, whereas those who died or underwent liver transplantation were designated as the death/transplant group.

RESULTS

There were 26 (56.5%) patients in the recovery group and 20 (43.5%) patients in the death/transplant group. Four patients (8.7%) underwent liver transplantation. After indeterminate causes (45.6%), genetic-metabolic diseases and drug-induced liver injury (DILI) were the most common cause with 15.2 and 13%, respectively. Genetic testing had a high yield of (6/31) in identifying monogenic disease associated with ALF. Younger age, lower Glasgow Coma Scale and higher international normalized ratio (INR) on admission were predictors for poor prognosis. The death/transplant group had longer intensive care unit stay ( P  < 0.001), and on admission they had more advanced hepatic encephalopathy ( P  < 0.005), more prolonged prothrombin time ( P  < 0.001), higher lactate ( P  < 0.006), higher total and direct bilirubin ( P  < 0.008) and ( P  < 0.001), respectively.

CONCLUSION

Genetic, metabolic and DILI causes constituted the most common cause of PALF after indeterminate causes. The use of genetic testing can improve diagnostic rates in special cases, but we could not assess the effect of genetic testing on prognosis. The overall survival rate in our study was 65.2%. Younger age, higher admission INR and lower Glasgow coma scale were indicators of poor prognosis.

Long-term outcomes of pediatric liver transplantation in acute liver failure vs end-stage chronic liver disease: A retrospective observational study

BACKGROUND

Children with acute liver failure (ALF) who meet the criteria are eligible for super-urgent transplantation, whereas children with end-stage chronic liver disease (ESCLD) are usually transplanted electively. Pediatric liver transplantation (PLT) in ALF and ESCLD settings has been well described in the literature, but there are no studies comparing the outcomes in these two groups.

AIM

To determine if there is a difference in post-operative complications and survival outcomes between ALF and ESCLD in PLT.

METHODS

This was a retrospective observational study of all primary PLTs performed at a single center between 2000 and 2019. ALF and ESCLD groups were compared for pretransplant recipient, donor and operative parameters, and post-operative outcomes including graft and patient survival.

RESULTS

Over a 20-year study period, 232 primary PLTs were performed at our center; 195 were transplanted for ESCLD and 37 were transplanted for ALF. The ALF recipients were significantly older (median 8 years vs 5.4 years; P = 0.031) and heavier (31 kg vs 21 kg; P = 0.011). Living donor grafts were used more in the ESCLD group (34 vs 0; P = 0.006). There was no difference between the two groups concerning vascular complications and rejection, but there were more bile leaks in the ESCLD group. Post-transplant patient survival was significantly higher in the ESCLD group: 1-, 5-, and 10-year survival rates were 97.9%, 93.9%, and 89.4%, respectively, compared to 78.3%, 78.3%, and 78.3% in the ALF group (P = 0.007). However, there was no difference in 1-, 5-, and 10-year graft survival between the ESCLD and ALF groups (90.7%, 82.9%, 77.3% vs 75.6%, 72.4%, and 66.9%; P = 0.119).

CONCLUSION

Patient survival is inferior in ALF compared to ESCLD recipients; the main reason is death in the 1^st year post-PLT in ALF group. Once the ALF children overcome the 1^st year after transplant, their survival stabilizes, and they have good long-term outcomes.

Heart rate variability is associated with encephalopathy and outcomes in pediatric acute liver failure

BACKGROUND

More than half of children with pediatric acute liver failure (PALF) experience hepatic encephalopathy (HE), which is related to poor outcomes; however, HE is difficult to diagnose in children. The objective of this study was to evaluate if heart rate variability (HRV), a continuous measure of autonomic nervous system function, was related to the presence and severity of HE as well as clinical outcomes in children with PALF.

METHODS

We conducted a retrospective observational cohort study of 38 critically ill children with PALF to examine the association between HRV and HE severity and clinical outcome. HRV was estimated using the integer HRV (HRVi). Categorical variables were compared using the Fisher Exact test and continuous variables were compared using Kruskal-Wallis tests. Associations between grades of HE and minimum and median HRVi were evaluated with Pearson's correlation, with p values <0.05 considered significant.

RESULTS

A more negative median and minimum HRVi, indicating poorer autonomic nervous system function, was significantly associated with abnormal EEG findings, presence of HE, and poor outcomes (death or listing for transplant).

CONCLUSIONS

Heart rate variability may hold promise to predict outcomes in children with PALF, but these findings should be replicated in a larger sample.

IMPACT

The findings of our study suggest that heart rate variability is associated with clinical outcomes in children with acute liver failure, a cohort for which prognostics are challenging, especially in young children and infants. Use of heart rate variability in the clinical setting may facilitate earlier detection of children with pediatric acute liver failure (PALF) at high risk for severe hepatic encephalopathy and poor outcomes. Identification of children with PALF at high risk of decompensation may assist clinicians in making decisions about liver transplantation, an important, but resource-limited, treatment of PALF.

Emergencies in paediatric hepatology

The aetiology of several liver diseases in children is age specific and many of these conditions have significant and potentially long-term clinical repercussions if not diagnosed early and managed in a timely fashion. We address 5 clinical scenarios that cover most of the diagnostic and therapeutic emergencies in children: infants with liver disease; acute liver failure; management of bleeding varices; liver-based metabolic disorders; and liver tumours and trauma. A wide spectrum of conditions that cause liver disease in infants may present as conjugated jaundice, which could be the only symptom of time-sensitive disorders - such as biliary atresia, metabolic disorders, infections, and haematological/alloimmune disorders - wherein algorithmic multistage testing is required for accurate diagnosis. In infantile cholestasis, algorithmic multistage tests are necessary for an accurate early diagnosis, while vitamin K, specific milk formulae and disease-specific medications are essential to avoid mortality and long-term morbidity. Management of paediatric acute liver failure requires co-ordination with a liver transplant centre, safe transport and detailed age-specific aetiological work-up - clinical stabilisation with appropriate supportive care is central to survival if transplantation is indicated. Gastrointestinal bleeding may present as the initial manifestation or during follow-up in patients with portal vein thrombosis or chronic liver disease and can be managed pharmacologically, or with endoscopic/radiological interventions. Liver-based inborn errors of metabolism may present as encephalopathy that needs to be recognised and treated early to avoid further neurological sequelae and death. Liver tumours and liver trauma are both rare occurrences in children and are best managed by a multidisciplinary team in a specialist centre.

The Role of Predictive Models in the Assessment of the Poor Outcomes in Pediatric Acute Liver Failure

OBJECTIVES

In children, acute liver failure (ALF) is a severe condition with high mortality. As some patients need liver transplantation (LT), it is essential to predict the fatal evolution and to refer them early for LT if needed. Our study aimed to evaluate the prognostic criteria and scores for assessing the outcome in children with ALF.

METHODS

Data of 161 children with ALF (54.66% female, mean age 7.66 ± 6.18 years) were analyzed based on final evolution (32.91% with fatal evolution or LT) and etiology. We calculated on the first day of hospitalization the PELD score (109 children), MELD, and MELD-Na score (52 children), and King's College Criteria (KCC) for all patients. The Nazer prognostic index and Wilson index for predicting mortality were calculated for nine patients with ALF in Wilson's disease (WD).

RESULTS

PELD, MELD, and MELD-Na scores were significantly higher in patients with fatal evolution (21.04 ± 13.28 vs. 13.99 ± 10.07, p = 0.0023; 36.20 ± 19.51 vs. 20.08 ± 8.57, p < 0.0001; and 33.07 ± 8.29 vs. 20.08 ± 8.47, p < 0.0001, respectively). Moreover, age, bilirubin, albumin, INR, and hemoglobin significantly differed in children with fatal evolution. Function to etiology, PELD, MELD, MELD-Na, and KCC accurately predicted fatal evolution in toxic ALF (25.33 vs. 9.90, p = 0.0032; 37.29 vs. 18.79, p < 0.0001; 34.29 vs. 19.24, p = 0.0002, respectively; with positive predicting value 100%, negative predicting value 88.52%, and accuracy 89.23% for King's College criteria). The Wilson index for predicting mortality had an excellent predictive strength (100% sensibility and specificity), better than the Nazer prognostic index.

CONCLUSIONS

Prognostic scores may be used to predict the fatal evolution of ALF in children in correlation with other parameters or criteria. Early estimation of the outcome of ALF is essential, mainly in countries where emergency LT is problematic, as the transfer to a specialized center could be delayed, affecting survival chances.

North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition Position Paper on the Diagnosis and Management of Pediatric Acute Liver Failure

ABSTRACT

Pediatric acute liver failure (PALF) is a rare, rapidly progressive clinical syndrome with significant morbidity and mortality. The phenotype of PALF manifests as abrupt onset liver dysfunction, which can be brought via disparate etiology. Management is reliant upon intensive clinical care and support, often provided by the collaborative efforts of hepatologists, critical care specialists, and liver transplant surgeons. The construction of an age-based diagnostic approach, the identification of a potential underlying cause, and the prompt implementation of appropriate therapy can be lifesaving; however, the dynamic and rapidly progressive nature of PALF also demands that diagnostic inquiries be paired with monitoring strategies for the recognition and treatment of common complications of PALF. Although liver transplantation can provide a potential life-saving therapeutic option, the ability to confidently determine the certainness that liver transplant is needed for an individual child has been hampered by a lack of adequately tested clinical decision support tools and accurate predictive models. Given the accelerated progress in understanding PALF, we will provide clinical guidance to pediatric gastroenterologists and other pediatric providers caring for children with PALF by presenting the most recent advances in diagnosis, management, pathophysiology, and associated outcomes.

Multiple organ involvement and ICU considerations for the care of acute liver failure (ALF) and acute on chronic liver failure (ACLF) in children

Liver disease results in approximately 15,000 pediatric hospitalizations per year in the United States and is a significant burden to child health. Major etiologies of liver failure and indications for transplantation in children include: biliary atresia, metabolic/genetic conditions, toxins, infections, tumors, and immune-mediated liver/biliary injury. Children requiring transplantation are placed on the United Network of Organ Sharing waitlist including those with acute liver failure (ALF) and acute on chronic liver failure (ACLF). ALF is a clinical syndrome in which a previously healthy child develops rapid-onset hepatic dysfunction, and becomes critically ill with multiple organ dysfunction within days. ACLF, by contrast, is generally described as an acute decompensation of pre-existing chronic liver disease (CLD) brought on by a precipitating event, with higher risk of mortality. Children with ALF and ACLF receive multidisciplinary care in pediatric intensive care units (ICUs) due to multiple organ system involvement and high risk of decompensation in these patients. The care of these patients requires a holistic approach that addresses the complex interplay between hepatic and extra-hepatic organ systems. This review will define and describe ALF and ACLF in the pediatric population, and outline the effects of ALF and ACLF on individual organ systems with diagnostic and management considerations in the ICU while awaiting liver transplantation.

Study of Acute Liver Failure in Children Using Next Generation Sequencing Technology

OBJECTIVE

To use next generation sequencing (NGS) technology to identify undiagnosed, monogenic diseases in a cohort of children who suffered from acute liver failure (ALF) without an identifiable etiology.

STUDY DESIGN

We identified 148 under 10 years of age admitted to King's College Hospital, London, with ALF of indeterminate etiology between 2000 and 2018. A custom NGS panel of 64 candidate genes known to cause ALF and/or metabolic liver disease was constructed. Targeted sequencing was carried out on 41 children in whom DNA samples were available. Trio exome sequencing was performed on 4 children admitted during 2019. A comparison of the clinical characteristics of those identified with biallelic variants against those without biallelic variants was then made.

RESULTS

Homozygous and compound heterozygous variants were identified in 8 out of 41 children (20%) and 4 out of 4 children (100%) in whom targeted and exome sequencing were carried out, respectively. The genes involved were NBAS (3 children); DLD (2 children); and CPT1A, FAH, LARS1, MPV17, NPC1, POLG, SUCLG1, and TWINK (1 each). The 12 children who were identified with biallelic variants were younger at presentation and more likely to die in comparison with those who did not: median age at presentation of 3 months and 30 months and survival rate 75% and 97%, respectively.

CONCLUSIONS

NGS was successful in identifying several specific etiologies of ALF. Variants in NBAS and mitochondrial DNA maintenance genes were the most common findings. In the future, a rapid sequencing NGS workflow could help in reaching a timely diagnosis and facilitate clinical decision making in children with ALF.

Differential Diagnosis of Acute Liver Failure in Children: A Systematic Review

PURPOSE

To develop a probability-based differential diagnosis for pediatric acute liver failure (PALF) based on age and socioeconomic status of the country of origin.

METHODS

Comprehensive literature search using PubMed, EMBASE, and SCOPUS databases was performed. Children 0-22 years of age who met PALF registry criteria were included. Articles included >10 children, and could not be a case report, review article, or editorial. No language filter was utilized, but an English abstract was required. Etiology of PALF, age of child, and country of origin was extracted from included articles.

RESULTS

32 full text articles were reviewed in detail; 2,982 children were included. The top diagnosis of PALF in developed countries was acetaminophen toxicity (9.24%; 95% CredI 7.99-10.6), whereas in developing countries it was Hepatitis A (28.9%; 95% CredI 26.3-31.7). In developed countries, the leading diagnosis of PALF in children aged <1 year was metabolic disorder (17.2%; 95% CredI 10.3-25.5), whereas in developing countries it was unspecified infection (39.3%; CredI 27.6-51.8). In developed countries, the leading diagnosis in children aged >1 year was Non-A-B-C Hepatitis (8.18%; CredI 5.28-11.7), whereas in developing countries it was Hepatitis A (32.4%; CredI 28.6-36.3).

CONCLUSION

The leading causes of PALF in children aged 0-22 years differ depending on the age and developmental status of their country of origin, suggesting that these factors must be considered in the evaluation of children with PALF.

Neurocritical care monitoring of encephalopathic children with acute liver failure: A systematic review

Research on non-invasive neuromonitoring specific to PALF is limited. This systematic review identifies and synthesis the existing literature on non-invasive approaches to monitoring for neurological sequelae in patients with PALF. A series of literature searches were performed to identify all publications pertaining to five different non-invasive neuromonitoring modalities, in line with PRISMA guidelines. Each modality was selected on the basis of its potential for direct or indirect measurement of cerebral perfusion; studies on electroencephalographic monitoring were therefore not sought. Data were recorded on study design, patient population, comparator groups, and outcomes. A preponderance of observational studies was observed, most with a small sample size. Few incorporated direct comparisons of different modalities; in particular, comparison to invasive intracranial pressure monitoring was largely lacking. The integration of current evidence is considered in the context of the clinically significant distinctions between pediatric and adult ALF, as well as the implications for planning of future investigations to best support the evidence-based clinical care of these patients.

Acute Liver Failure due to Wilson Disease: Eight Years of the National Liver Transplant Program in Uruguay

INTRODUCTION AND AIM

Wilson's disease (WD) is an uncommon cause of acute liver failure (ALF). Our aim was to describe clinical features, diagnostic findings, treatments, and outcomes of patients with ALF due to WD.

MATERIAL AND METHODS

Retrospective medical record reviews of all patients with ALF due to WD in eight years in Uruguay.

RESULTS

WD was the cause of six (15%) of thirty-nine ALF cases. All patients were females, with a mean age of 18 years. Four patients presented with hyperacute liver failure and two with acute failure. Jaundice was the main complaint of all patients. Mean total bilirubin (TB), alkaline phosphatase (AP), AST, and ALT were 27.5 mg/dL, 45.5 lU/l, 156 IU/L, and 51 IU/L, respectively. Ceruloplasmin levels were low in four patients, urinary cooper was high in four, and two had Kayser-Fleischer rings. All patients had Coombs-negative hemolytic anemia, acute kidney injury, histochemical identifiable copper, and advanced fibrosis on liver histology. The average MELD score was 36. All patients were treated with d-penicillamine and listed for urgent liver transplantation (LT). Prometheus® was performed in one patient. Three patients died: two without LT and one after LT. Three patients survived: one without LT (New Wilson Index<11) and two with LT. The referral time to the program and the total time (referral plus waiting list time) were longer for non-survivors than for survivors (14 vs. 3 days and 23 vs. 8 respectively).

CONCLUSION

All cases had typical clinical, analytical and histopathology characteristics. Early referral was determinant of prognosis.

Medical Management of Acute Liver Failure

Pediatric acute liver failure is a rapidly progressive, life-threatening, and devastating illness in children without preexisting liver disease. Due to the rarity and heterogeneity of this syndrome, there is a significant lack of data to guide evaluation and management of this disease. Most of our practice is extrapolated from adult literature and guidelines. This leads to significant controversies in medical management of acute liver failure in children. With advances in critical care, there has been a tremendous improvement in outcomes with decreased morbidity and mortality; however, there is a dire need for more research in this field. This chapter discusses challenges as well as controversies in diagnostic evaluation and management of this rare but potentially fatal disease. Latest developments in supportive care of liver failure, including advances in the area of liver support systems, are also discussed.

Successful management of acute liver failure in Italian children: A 16-year experience at a referral centre for paediatric liver transplantation

BACKGROUND

Identifying the causes of acute liver failure (ALF) and predictors of death or liver transplantation (LTX) is crucial to decide its management. We aimed to describe features and outcome of ALF in Italian children.

METHODS

Retrospective review of cases presenting between 1996-2012. ALF was defined by high transaminases, INR ≥2.0 regardless of hepatic encephalopathy (HE), no evidence of underlying chronic liver disease.

RESULTS

55 children (median age 2.6 years, range 0.1-15.1; M/F=31/24) had ALF due to autoimmune hepatitis (AIH) in 10 (18%), metabolic disorders in 9 (17%), paracetamol overdose in 6 (11%), mushroom poisoning in 3 (5%), viral infection in 1 (2%), indeterminate in 26 (47%); 25/55 recovered with supportive management (45%); 28/55 underwent LTX and 2 died on the waiting list (55%). On multivariate analysis severity of HE grade 3-4 and bilirubin ≥12mg/dl were independent predictors of death or LTX (p<0.05). After a median follow up of 4 years (range 2-15.0 years) the overall survival rate was 93%.

CONCLUSION

Children with ALF can be managed successfully with combined medical treatment and transplantation, warranting a survival rate similar to children transplanted because of chronic conditions. In our cohort of patients severe HE and high bilirubin on admission were independent predictors of the need of LTX.

Spectral Electroencephalogram Analysis for the Evaluation of Encephalopathy Grade in Children With Acute Liver Failure

OBJECTIVE

Spectral electroencephalogram analysis is a method for automated analysis of electroencephalogram patterns, which can be performed at the bedside. We sought to determine the utility of spectral electroencephalogram for grading hepatic encephalopathy in children with acute liver failure.

DESIGN

Retrospective cohort study.

SETTING

Tertiary care pediatric hospital.

PATIENTS

Patients between 0 and 18 years old who presented with acute liver failure and were admitted to the PICU.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Electroencephalograms were analyzed by spectral analysis including total power, relative δ, relative θ, relative α, relative β, θ-to-Δ ratio, and α-to-Δ ratio. Normal values and ranges were first derived using normal electroencephalograms from 70 children of 0-18 years old. Age had a significant effect on each variable measured (p < 0.03). Electroencephalograms from 33 patients with acute liver failure were available for spectral analysis. The median age was 4.3 years, 14 of 33 were male, and the majority had an indeterminate etiology of acute liver failure. Neuroimaging was performed in 26 cases and was normal in 20 cases (77%). The majority (64%) survived, and 82% had a good outcome with a score of 1-3 on the Pediatric Glasgow Outcome Scale-Extended at the time of discharge. Hepatic encephalopathy grade correlated with the qualitative visual electroencephalogram scores assigned by blinded neurophysiologists (rs = 0.493; p < 0.006). Spectral electroencephalogram characteristics varied significantly with the qualitative electroencephalogram classification (p < 0.05). Spectral electroencephalogram variables including relative Δ, relative θ, relative α, θ-to-Δ ratio, and α-to-Δ ratio all significantly varied with the qualitative electroencephalogram (p < 0.025). Moderate to severe hepatic encephalopathy was correlated with a total power of less than or equal to 50% of normal for children 0-3 years old, and with a relative θ of less than or equal to 50% normal for children more than 3 years old (p > 0.05). Spectral electroencephalogram classification correlated with outcome (p < 0.05).

CONCLUSIONS

Spectral electroencephalogram analysis can be used to evaluate even young patients for hepatic encephalopathy and correlates with outcome. Spectral electroencephalogram may allow improved quantitative and reproducible assessment of hepatic encephalopathy grade in children with acute liver failure.

Prognostic modeling in pediatric acute liver failure

Liver transplantation (LT) is the only proven treatment for pediatric acute liver failure (PALF). However, over a period of time, spontaneous native liver survival is increasingly reported, making us wonder if we are overtransplanting children with acute liver failure (ALF). An effective prognostic model for PALF would help direct appropriate organ allocation. Only patients who would die would undergo LT, and those who would spontaneously recover would avoid unnecessary LT. Deriving and validating such a model for PALF, however, encompasses numerous challenges. In particular, the heterogeneity of age and etiology in PALF, as well as a lack of understanding of the natural history of the disease, contributed by the availability of LT has led to difficulties in prognostic model development. Several prognostic laboratory variables have been identified, and the incorporation of these variables into scoring systems has been attempted. A reliable targeted prognostic model for ALF in Wilson's disease has been established and externally validated. The roles of physiological, immunological, and metabolomic parameters in prognosis are being investigated. This review discusses the challenges with prognostic modeling in PALF and describes predictive methods that are currently available and in development for the future. Liver Transplantation 22 1418-1430 2016 AASLD.

Outcomes of Children With and Without Hepatic Encephalopathy From the Pediatric Acute Liver Failure Study Group

OBJECTIVES

Hepatic encephalopathy (HE) is challenging to identify in children with acute liver failure and was not a requirement for enrollment into the Pediatric Acute Liver Failure Study Group (PALFSG). The outcomes of PALFSG participants presenting with and without HE are presented.

METHODS

PALFSG participants were classified based on daily assessment of HE during the first 7 days following study enrollment: group 1-never developed HE; group 2-no HE at enrollment with subsequent HE development; and group 3-HE at study enrollment. Clinical and biochemical parameters and outcomes of death, spontaneous recovery, or liver transplantation were compared between groups.

RESULTS

Data from 769 PALFSG (54% boys; median age 4.2 years; range 0-17.9 years) participants were analyzed, with 277 in group 1 (36%), 83 in group 2 (11%), and 409 in group 3 (53%). Mortality occurred in 11% of all participants and was highest among group 3 participants who demonstrated persistent grade III-IV HE (55%) or showed progression of HE (26%). Eleven (4%) group 1 participants died within 21 days of enrollment. Spontaneous recovery was highest in group 1 (79%) and lowest in group 2 (25%; P < 0.001).

CONCLUSIONS

Mortality 21 days after enrollment was highest in participants enrolled with severe HE (grades III or IV) or demonstrating HE progression. Four percent of participants without recorded clinical HE in the 7 days after enrollment, however, died within 21 days. Improved assessment of neurological injury and pediatric acute liver failure prognostication schema are needed.

Pediatric acute liver failure: variations in referral timing are associated with disease subtypes

In pediatric acute liver failure (PALF), rapid referral to a transplant center (TC) is advocated. Clinical variability of PALF may influence referral timing. We aimed to analyze early or late timing of referral in relation to clinical characteristics and outcome in PALF. We conducted a retrospective, single-center, comparative analysis of clinical and liver function parameters in two PALF cohorts (n = 23 per cohort): cohort 1 (early referral, duration of in-patient care before referral (DCR) <7 days) vs. cohort 2 (late referral, DCR ≥ 7 days). Compared to late referrals, patients referred early were more frequently non-icteric and encephalopathic at initial presentation (n = 14 vs. 5 and n = 13 vs. 4, each p < 0.05). Early referred PALF patients had lower hepatic encephalopathy (HE) grades and bilirubin (grade 1 vs. 2, p < 0.02; 215 vs. 439 μmol/l, p < 0.001, respectively) but higher alanine aminotransferase (ALAT) levels (4,340 vs. 963 U/l, p < 0.001). Cumulative poor prognostic indicators were lower in early referrals (2 vs. 4, p < 0.001). In multivariate analysis, subacute liver failure (SLF >7 days between disease onset and development of encephalopathy) was independently associated with late referral (relative risk 9.48; 95 % CI 1.37-64.85, p < 0.02). Differences in survival to discharge were not significant.

CONCLUSION

In PALF, referral timing variability is associated with distinct clinical and liver function patterns. Early recognition of prognostic indicators and of SLF may help to improve referral timing and thus PALF management.

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

BACKGROUND

Supportive care as a bridge to transplant or recovery remains challenging in children suffering from acute liver failure (ALF). We report our experience in children using the Molecular Absorbent Recirculating System (MARS(®)).

METHODS

Retrospective data from children receiving therapy using MARS(®) from October 2009 to October 2012 were included in this single-center retrospective study. Patient characteristics, clinical presentation and complications of ALF, clinical and biological data before and after each MARS(®) session, technical modalities and adverse events were recorded.

RESULTS

A total of six children underwent 17 MARS(®) sessions during the study period. Two adolescents were treated with the adult filter MARSFLUX(®) and four infants were treated with the MiniMARS(®) filter. The mean PEdiatric Logistic Dysfunction (PELOD) score at admission was 19 (range 11-33). All patients were mechanically ventilated, and four had acute kidney injury. The neurological course improved in one case, judged as stable in two cases and worsened in one case; data were unavailable in two cases. Mean serum ammonia levels decreased significantly following treatment with MARS(®) from an initial 89 ± 29 to 58 ± 35 mcmol/L (p = 0.02). No other significant biological improvement was observed. Hemodynamic status improved/remained unchanged in the adolescent group, but in the infants four of the seven sessions were poorly tolerated and two sessions were aborted. Three patients died, two were successfully transplanted and one recovered without transplantation.

CONCLUSION

In our experience, treatment with MARS(®) is associated with encouraging results in adolescents, but it needs modification for very sick infants to improve tolerance.

EEG abnormalities are associated with increased risk of transplant or poor outcome in children with acute liver failure

OBJECTIVES

There are limited data on the incidence of seizures and utility of brain imaging and electroencephalogram (EEG) to predict outcome of children with acute liver failure (ALF). We investigated the association between hepatic encephalopathy (HE) scores, abnormal EEG or neuroimaging, and short-term outcome.

METHODS

Single-center retrospective observational study of infants and children with ALF who underwent continuous EEG monitoring and brain imaging within 24 hours of admission to the intensive care unit (ICU).

RESULTS

A total of 19 patients with ALF with a mean age of 6.8 ± 1.5 years were evaluated. The majority of cases (74%) were indeterminate. Of the total, 10 patients (53%) survived to discharge without liver transplant (LT), 5 (26%) received LT, and 4 (21%) died without LT. Seizures occurred in only 2 cases (19%). Patients who had an abnormal EEG on admission (n = 7) were significantly more likely to die or require LT (P < 0.05, Fisher exact test). Patients with either an admission HE score ≤ 2, or liver injury unit score <222, combined with a normal or mildly abnormal EEG were more likely to survive without LT. Neuroimaging was normal in the majority of cases (87%) and was not associated with outcome.

CONCLUSIONS

Children with a moderate or severe abnormality of EEG background on admission were significantly more likely to require LT or to die. Children with an HE score ≤ 2, and a normal or only mildly abnormal EEG, were significantly more likely to survive without needing LT. These findings are an initial step toward distinguishing patients with ALF who may recover spontaneously from those who will require LT.

Improved outcomes in liver transplantation in children with acute liver failure

OBJECTIVE

The aim of our study was to review the experiences of a living donor-dominant transplantation program for children with acute liver failure (ALF).

METHODS

Data were derived from the retrospective chart review of 50 children with ALF in a major liver center in the Republic of Korea.

RESULTS

A total of 50 children with ALF underwent 47 (94%) primary living donor liver transplantations and 3 (6%) cadaveric liver transplantations. The cumulative survival rates of the grafts at 1 and 5 years were 81.9% and 79.2%, respectively. The overall retransplantation rate was 12%. The cumulative survival rates of these patients at 1 and 5 years were all 87.9%. Most incidents of mortality followed the failure of the preceding graft. We observed no mortalities among donors. Based on multivariate analysis, children who had pretransplant thrombocytopenia or had to use the molecular adsorbent recycling system preoperatively were related to the graft loss. Age younger than 2 years and a hyperacute onset (within 7 days) of hepatic encephalopathy were associated with pretransplant thrombocytopenia.

CONCLUSIONS

Living donor-dominant transplantation program in the present study demonstrates tolerable achievements in terms of clinical outcomes of recipients and donors; however, putative factors, such as pretransplant thrombocytopenia, seem to play unclear roles in a poor prognosis following transplantation.

Differential clinical characteristics of acute liver failure caused by hemophagocytic lymphohistiocytosis in children

BACKGROUND

Children with acute liver failure (ALF) caused by hemophagocytic lymphohistiocytosis (HLH) may be at risk of undergoing unnecessary liver transplantation (LT). The aim of this study was to compare the characteristics of ALF caused by HLH with those of ALF of unknown etiology in children.

METHODS

The clinical features and laboratory findings for eight children with ALF caused by HLH (ALF-HLH group) and 27 children with ALF of unknown etiology (ALF-UK group) were retrospectively compared by reviewing medical records.

RESULTS

The ALF-HLH group had a higher incidence of pleural effusion, C-reactive protein elevation (especially >5 mg/dL), thrombocytopenia, anemia, fever, splenomegaly, and hypoalbuminemia (<2.5 mg/dL), and a higher in-hospital mortality rate. No significant differences were found in the white blood cell count, liver enzymes, coagulation profile, or incidence of hepatomegaly.

CONCLUSIONS

LT should be performed only after it is proven that ALF is not caused by HLH, if a child with ALF shows the differential clinical features of ALF caused by HLH. Further research with larger sample sizes, however, is needed.

Selective head cooling for the treatment of neurologic complications of acute liver failure in a newborn with disseminated herpes infection

Background

Neurologic complications of pediatric acute liver failure (ALF) are a major determinant of outcome. Management of these complications, including increased intracranial pressure (ICP) is largely supportive. Although hypothermia is an effective treatment for perinatal asphyxia and is used to reduce ICP following traumatic brain injury, it has not been evaluated for neurologic complications of ALF in the newborn.

Methods

Case report.

Results

We present a case of neonatal herpes simplex virus (HSV)-associated ALF with profound neurologic impairment and increased ICP. The patient was treated with selective head cooling, and monitored with transcranial doppler (TCD) studies of cerebral blood flow velocity, and electroencephalograms (EEG). The duration of head cooling was influenced by absent diastolic flow on TCDs, which subsequently improved during hypothermia. Continuous EEGs captured subclinical seizures, which improved with antiepileptic medications. Her death was attributed to a massive pulmonary hemorrhage and a hypoxemic cardiac arrest secondary to significant coagulopathy.

Conclusion

This case demonstrates that selective head cooling may attenuate increased ICP in neonatal encephalopathy, and that TCDs may guide management in the absence of invasive monitoring.

Pediatric acute liver failure: etiology, outcomes, and the role of serial pediatric end-stage liver disease scores

To describe etiology, short-term outcomes and prognostic accuracy of serial PELD scores in PALF. Retrospective analysis of children aged ≤16 yr, admitted with PALF under the QLTS, Brisbane, Australia, between 1991 and 2011. PELD-MELD scores were ascertained at three time points (i) admission (ii), meeting PALF criteria, and (iii) peak value. Fifty-four children met criteria for PALF, median age 17 months (1 day-15.6 yr) and median weight 10.2 kg (1.9-57 kg). Etiology was known in 69%: 26% metabolic, 15% infective, 13% drug-induced, 6% autoimmune, and 9% hemophagocytic lymphohistiocytosis. Age <3 months and weight <4.7 kg predicted poor survival in non-transplanted children. Significant independent predictors of poor outcome (death or LT) were peak bilirubin > 220 μm/L and peak INR > 4. Serial PELD-MELD scores were higher in the 17 (32%) transplant recipients (mean: [i] 26.8, [ii] 31.8, [iii] 42.6); highest in the 12 (22%) non-transplanted non-survivors (mean: [i] 31.6, [ii] 37.2, [iii] 45.7) compared with the 25 (46%) transplant-free survivors (mean: [i] 25.3, [ii] 26.0, [iii] 30.3). PELD-MELD thresholds of ≥27 and ≥42 at (ii) meeting PALF criteria and (iii) peak predicted poor outcome (p < 0.001). High peak bilirubin and peak INR predict poor outcome and serial PELD-MELD is superior to single admission PELD-MELD score for predicting poor outcome.

Evaluation of the liver injury unit scoring system to predict survival in a multinational study of pediatric acute liver failure

OBJECTIVE

To examine the predictive value of the Liver Injury Units (LIU) and admission values (aLIU) of bilirubin and prothrombin time and international normalized ratio scores in a large cohort from the Pediatric Acute Liver Failure (PALF) Study Group, a multinational prospective study.

STUDY DESIGN

LIU and aLIU scores were calculated for 461 and 579 individuals, respectively, enrolled in the PALF study from 1999 to 2008. Receiver operator characteristic curves were used to evaluate the scores with respect to survival without liver transplantation (LT), death, or LT by 21 days after enrollment.

RESULTS

At 21 days, 50.3% of participants were alive without LT, 36.2% underwent LT, and 13.4% died. The c-indices for transplant-free survival were 0.81 based on the LIU score with the international normalized ratio (95% CI, 0.78-0.85) and 0.76 based on the aLIU score (95% CI, 0.72-0.79). The LIU score predicted LT better than it predicted death (c-index for LT 0.84, c-index for death 0.76).

CONCLUSION

Based on data from a large, multicenter cohort of patients with PALF, the LIU score was a better predictor of transplant-free survival than was the aLIU score. The LIU score might be a helpful, dynamic tool to predict clinical outcomes in patients with PALF.

Intravenous N-acetylcysteine in pediatric patients with nonacetaminophen acute liver failure: a placebo-controlled clinical trial

N-acetylcysteine (NAC) was found to improve transplantation-free survival in only those adults with nonacetaminophen (non-APAP) acute liver failure (ALF) and grade 1-2 hepatic encephalopathy (HE). Because non-APAP ALF differs significantly between children and adults, the Pediatric Acute Liver Failure (PALF) Study Group evaluated NAC in non-APAP PALF. Children from birth through age 17 years with non-APAP ALF enrolled in the PALF registry were eligible to enter an adaptively allocated, doubly masked, placebo-controlled trial using a continuous intravenous infusion of NAC (150 mg/kg/day in 5% dextrose in water [D5W]) or placebo (D5W) for up to 7 days. The primary outcome was 1-year survival. Secondary outcomes included liver transplantation-free survival, liver transplantation (LTx), length of intensive care unit (ICU) and hospital stays, organ system failure, and maximum HE score. A total of 184 participants were enrolled in the trial with 92 in each arm. The 1-year survival did not differ significantly (P = 0.19) between the NAC (73%) and placebo (82%) treatment groups. The 1-year LTx-free survival was significantly lower (P = 0.03) in those who received NAC (35%) than those who received placebo (53%), particularly, but not significantly so, among those less than 2 years old with HE grade 0-1 (NAC 25%; placebo 60%; P = 0.0493). There were no significant differences between treatment arms for hospital or ICU length of stay, organ systems failing, or highest recorded grade of HE.

CONCLUSION

NAC did not improve 1-year survival in non-APAP PALF. One-year LTx-free survival was significantly lower with NAC, particularly among those <2 years old. These results do not support broad use of NAC in non-APAP PALF and emphasizes the importance of conducting controlled pediatric drug trials, regardless of results in adults.

King's College Hospital Criteria for non-acetaminophen induced acute liver failure in an international cohort of children

OBJECTIVE

To validate King's College Hospital criteria (KCHC) in children with non-acetaminophen induced pediatric acute liver failure (PALF) and to determine whether re-optimizing the KCHC would improve predictive accuracy.

STUDY DESIGN

We used the PALF study group database. Primary outcomes were survival without liver transplantation vs death at 21 days following enrollment. Classification and regression tree analysis was used to determine if modification of KCHC parameters would improve classification of death vs survival.

RESULTS

Among 163 patients who met KCHC, 54 patients (33.1%) died within 21 days. Sensitivity of KCHC in this cohort was significantly lower than in the original study (61% vs 91%, P = .002), and specificity did not differ significantly. The positive predictive value (PPV) and negative predictive value (NPV) of KCHC for this cohort was 33% and 88% respectively. Classification and regression tree analysis yielded the following optimized parameters to predict death: grade 2-4 encephalopathy, international normalized ratio >4.02, and total bilirubin >2.02 mg/dL. These parameters did not improve PPV, but NPV was significantly better (88% vs 92%, P < .0001).

CONCLUSIONS

KCHC does not reliably predict death in PALF. With a PPV of 33%, twice as many participants who met KCHC recovered spontaneously than died, indicating that using KCHC may cause over utilization of liver transplantation. Re-optimized cutpoints for KCHC parameters improved NPV, but not PPV. Parameters beyond the KCHC should be evaluated to create a predictive model for PALF.

Predictors of outcome in children with acute viral hepatitis and coagulopathy

The presence of coagulopathy in acute viral hepatitis (AVH) in children raises issues about prognosis and need for liver transplantation. We evaluated factors predicting outcome in such patients and determined the applicability of the paediatric acute liver failure study group (PALFSG) definition of acute liver failure (ALF) of coagulopathy alone in comparison with coagulopathy and encephalopathy. Children with AVH (clinical features, raised transaminases and positive viral serology) with uncorrectable coagulopathy [prothrombin time (PT) > 15 s] with or without hepatic encephalopathy (HE) were enrolled. Comparative analysis was based on (i) outcome: survivors/nonsurvivors and (ii) ALF criteria: group A coagulopathy (PT > 15 s) and encephalopathy and group B coagulopathy (PT > 20 s). We studied 130 children (86 boys, mean age 7.5 ± 4.5 years): 86 recovered and 44 died. Single virus infection was present in 96 (74%), hepatitis A being the commonest (n-69). On multiple stepwise logistic regression analysis, age <3.5 years, serum bilirubin ≥ 16.7 mg/dL, PT ≥ 40.5 s and clinical signs of cerebral oedema were independent predictors of mortality. Mortality increased from 0% with single to 100% with four risk factors. Ninety-seven cases met the PALFSG criteria: group A-79 and group B-18. Group A subjects had higher mortality (55.6%vs 0%) and poorer liver functions (bilirubin 18.1 ± 8.9 vs 13.8 ± 6.9 mg/dL, PT 63.9 ± 35.1 vs 27.2 ± 5.2 s) than group B. PT deteriorated significantly with the appearance and progression of HE. One-third of children with AVH with coagulopathy die without transplantation. Age <3.5 years, bilirubin ≥ 16.7 mg/dL, PT ≥ 40.5 s and signs of cerebral oedema are predictors of poor outcome. Children with encephalopathy and coagulopathy have a poorer outcome than those with coagulopathy alone.

Invasive intracranial pressure monitoring is a useful adjunct in the management of severe hepatic encephalopathy associated with pediatric acute liver failure

OBJECTIVE

Pediatric acute liver failure is often accompanied by hepatic encephalopathy, cerebral edema, and raised intracranial pressure. Elevated intracranial pressure can be managed more effectively with intracranial monitoring, but acute-liver-failure-associated coagulopathy is often considered a contraindication for invasive monitoring due to risk for intracranial bleeding. We reviewed our experience with use of early intracranial pressure monitoring in acute liver failure in children listed for liver transplantation.

DESIGN AND PATIENTS

Retrospective review of all intubated pediatric acute liver failure patients with grade III and grade IV encephalopathy requiring intracranial pressure monitoring and evaluated for potential liver transplant who were identified from an institutional liver transplant patient database from 1999 to 2009.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

A total of 14 patients were identified who met the inclusion criteria. Their ages ranged from 7 months to 20 yrs. Diagnoses of acute liver failure were infectious (three), drug-induced (seven), autoimmune hepatitis (two), and indeterminate (two). Grade III and IV encephalopathy was seen in ten (71%) and four (29%) patients, respectively. Computed tomography scans before intracranial pressure monitor placement showed cerebral edema in five (35.7%) patients. Before intracranial pressure monitor placement, fresh frozen plasma, vitamin K, and activated recombinant factor VIIa were given to all 14 patients, with significant improvement in coagulopathy (p < .04). The initial intracranial pressure ranged from 5 to 50 cm H2O; the intracranial pressure was significantly higher in patients with cerebral edema by computed tomography (p < .05). Eleven of 14 (78%) patients received hypertonic saline, and three (22%) received mannitol for elevated intracranial pressure. Eight of 14 (56%) monitored patients were managed to liver transplant, with 100% surviving neurologically intact. Four of 14 (28%) patients had spontaneous recovery without liver transplant. Two of 14 (14%) patients died due to multiple organ failure before transplant. One patient had a small 9-mm intracranial hemorrhage but survived after receiving a liver transplant. No patient developed intracranial infection.

CONCLUSIONS

In our series of patients, intracranial pressure monitoring had a low complication rate and was associated with a high survival rate despite severe hepatic encephalopathy and cerebral edema in the setting of pediatric acute liver failure. In our experience, monitoring of intracranial pressure allowed interventions to treat increased intracranial pressure and provided additional information regarding central nervous system injury before liver transplant. Further study is warranted to confirm if monitoring allows more directed intracranial pressure therapy and improves survival in pediatric acute liver failure.

Decline in HAV-associated fulminant hepatic failure and liver transplant in children in Argentina after the introduction of a universal hepatitis A vaccination program

INTRODUCTION

Hepatitis A virus (HAV) infection is a vaccine-preventable disease. The most severe complication in children is fulminant hepatic failure (FHF), estimated to occur in 0.4% of cases; patients with FHF often require a liver transplant (LT). Following another outbreak of HAV infection in Argentina during 2003-2004, a one-dose HAV universal immunization (UI) program was started in 2005, resulting in a reduction in the incidence of HAV infection. We have investigated the impact of HAV UI on the trends in the occurrence of FHF and LT in children.

METHODS

All pediatric cases of FHF admitted to four pediatric centers in Buenos Aires during March 1993-July 2005 were retrospectively reviewed, and data of cases during August 2005-December 2008 were collected. Information about demography, HAV infections and vaccination status, diagnostic data for FHF using the Pediatric Acute Liver Failure criteria, clinical laboratory results, encephalopathy, the severity of liver disease using the Pediatric End Stage Liver Disease score, assessment of patients on the LT waiting list using King's College Criteria for LT, treatment given for FHF (pre- and post-transplant), and clinical outcome were collected using a case report form. The frequency and outcomes of HAV-associated FHF and LT cases before and after UI were analyzed.

RESULTS

During the pre-immunization period, March 1993-July 2005, 54.6% (N = 165) of FHF cases were caused by HAV; HAV-associated FHF cases peaked during 2003-2004. During the post-immunization period, August 2005-December 2008, only 27.7% (N = 18) of FHF cases were caused by HAV infection; only one of these patients had received the HAV vaccine (one dose only). The number of HAV-associated FHF cases decreased from 2005, and no cases were reported from November 2006-December 2008. Multivariate analyses showed that the association of FHF with HAV infection rather than other etiologies decreased with increasing age (P = 0.03), UI against HAV (P = 0.002), and anti-actin antibodies (P = 0.002), and increased with increasing weight (P = 0.0004).

CONCLUSIONS

The number of children with HAV-associated FHF in Argentina has strongly decreased since the initiation of the UI program. Further monitoring is required to confirm the long-term health and economic benefits of UI against HAV infection.

Comparison of Molecular Adsorbents Recirculating System (MARS) dialysis with combined plasma exchange and haemodialysis in children with acute liver failure

BACKGROUND

Molecular Adsorbents Recirculating System (MARS) is an extracorporeal liver support system eliminating albumin-bound and water-soluble substances. While it is increasingly applied in patients with acute liver failure (ALF), no comparison with standard dialysis methods has yet been performed.

METHODS

This is an analysis of ten children (0.1-18 years) with ALF, who underwent a total of 22 MARS sessions. Standard adult MARS sets were used in seven (23.5-72 kg) and MARS Mini in three children (2.8-13 kg). In eight children, MARS was alternated with combined plasma exchange (PE) and haemodialysis (HD) treatments. Mean treatment duration was 7.2 (6-10) h for MARS and 5.7 (4.5-6.6) h for PE/HD.

RESULTS

Standard MARS treatment only slightly decreased serum bilirubin (16.3 ± 6.5-13.8 ± 5.9 mg/dL) and ammonia (113 ± 62-99 ± 68 μmol/L) and international normalized ratio (INR) tended to increase (1.5 ± 0.3 and 2 ± 1.1). Mini-MARS did not reduce serum bilirubin (19.7 ± 3-20.5 ± 3.2 mg/dL), ammonia slightly decreased (70 ± 24-56 ± 9 μmol/L) and INR increased (2.5 ± 0.7-2.9 ± 1.1, all P = n.s.). In contrast, PE/HD reduced serum bilirubin (23 ± 8.4-14.7 ± 7 mg/dL), ammonia (120 ± 60-70 ± 40 μmol/L) and INR (2.4 ± 0.8-1.4 ± 0.1, all P < 0.05). Intraindividual comparison showed a slight increase in bilirubin by 2 ± 22% with MARS and a reduction by 37 ± 11% with PE/HD (P < 0.001 versus MARS) and a decrease in ammonia of 18 ± 27 and 39 ± 23% (P < 0.05). INR increased during MARS by 26 ± 41% and decreased with PE/HD by 37 ± 20% (P < 0.01). All treatment sessions were well tolerated. Five children died, including the three children treated with Mini-MARS.

CONCLUSION

Our experience suggests superior efficacy of combined PE/HD as compared to intermittent MARS therapy for treating ALF.

Chilean experience in liver transplantation for acute liver failure in children

BACKGROUND

Acute liver failure (ALF) in children is a life-threatening condition, associated with high mortality, and in almost one third of the cases, with no other therapeutic option than orthotopic liver transplant (OLT). The aim of this study was to present our experience with OLT for ALF in pediatric patients in Chile. Patients fulfilling the criteria for ALF who were transplanted in our centers were prospectively included in an excel Microsoft database. We analyzed demographics, etiology, surgical techniques, complications, and long-term results.

PATIENTS AND METHODS

Between 1994 and 2009, we transplanted 52 pediatric patients with ALF. The most frequent known etiology was acute hepatitis A in 9 cases (18%), but in 26 cases (50%) it was impossible to determine the etiology. Thirty- one patients were males (63%). The overall mean age was 7.5 years and the mean weight, 28.1 kg. Thirty-five (67%) received a cadaveric graft. Among them in 18 cases (34%) the liver had to be reduced but 17 (33%) received whole livers. There were 17 (33%) recipients of living-related livers. Twenty-two patients needed reoperation, including 13 due to surgical complications (59%) and 9 (41%) as planned interventions. Ten patients were retransplanted.

RESULTS

Actuarial survival of patients at 1 year was 80% and at 5 and 10 years, 72%. Graft survival at 1 year was 79%, at 5 years 69%, and at 10 years 50%.

CONCLUSION

We have reported a series of pediatric liver transplant patients due to ALF whose results were comparable to other reported series. Living donor transplantation for ALF should be considered and offers a low morbidity rate without mortality.

Herpes simplex virus sepsis and acute liver failure

Acute liver failure is a life threatening disease mostly triggered by drug-induced or toxic liver damage or viral hepatitis. Herpes Simplex virus (HSV) hepatitis is rare and accounts for only 1% of all acute liver failures. The importance of HSV-induced acute liver failure is based on its extremely severe clinical course with lethality rates of almost 75%. HSV hepatitis is just one of several clinical manifestations of HSV sepsis leading more frequently to encephalitis, pneumonia and esophagitis. Local herpes infection or recurrence of dermal lesions (herpes labialis, herpes genitalis), however, is common and account for the high prevalence of HSV-1 or HSV-2 infection in adults. Another rare entity is visual dissemination, which mostly affects immunocompromised patients. Compromised cellular immunity is a major risk factor for HSV sepsis because of either primary infection or reactivation of occult chronic HSV infection. Delayed diagnosis without antiviral therapy significantly contributes to the unfavorable outcome. Typically, anicteric hepatitis is seen in patients with HSV hepatitis. Because of its low incidence, however, and the lack of dermal manifestations, HSV hepatitis is rarely considered in the context of acute liver failure. In addition, diagnostic tests might not always be available. Therefore, it is a generally accepted consensus to begin antiviral therapy pre-emptively with acyclovir in cases of acute liver failure of unknown origin, in which high urgency (HU) liver transplantation remains the only therapeutical option. Even in the case of early specific therapy, sepsis may prevail and the indication for HU transplantation must be evaluated carefully. The outcome after liver transplantation for HSV-induced liver failure with reported survival rates of more than 40% is good. Because of the risk of recurrence, lifelong prophylaxis with acyclovir is recommended.

Living-related donor liver transplantation for children with fulminant hepatic failure in Israel

BACKGROUND

Liver transplantation is considered the treatment of choice for most children with deteriorating fulminant hepatic failure (FHF). Living-related donor liver transplantation (LDLT) has been suggested as an alternative to cadaveric liver transplantation to overcome the shortage of organ donors. However, experience with LDLT for children with FHF is limited in the Western world.

OBJECTIVE

To present the experience with LDLT for children with FHF in a major referral center in Israel.

METHODS

The files of all children who underwent primary LDLT for FHF were reviewed for demographic, clinical, and laboratory parameters before and after transplantation.

RESULTS

: During 1996 to 2007, 13 children diagnosed with FHF underwent primary LDLT. Median age was 4 years (range 0.75-14 years); the causes of FHF were acute hepatitis A in 4 patients and were unknown in 9 patients. Short-term complications, documented in 12 children, included mainly hepatic artery thrombosis (n = 5), which warranted retransplantation in 3 cases, and biliary leaks (n = 3). Three patients died within the first month after LDLT of severe intraoperative bleeding (n = 1), severe brain edema (n = 1), and multiorgan failure (n = 1). Long-term complications were less common and included mainly ascending cholangitis (n = 3). Patient survival rate was 68% at 1 year and 57% at 5 years. None of the donors had long-term complications.

CONCLUSIONS

Among children with FHF, LDLT can serve as a timely and lifesaving alternative to cadaveric donation, and could reduce the dependence on cadaveric livers in this setting.

Clinicopathologic spectrum of massive and submassive hepatic necrosis in infants and children

Clinicopathologic features of 45 patients with fulminant hepatic failure due to massive or submassive hepatic necrosis were studied. Both percutaneous biopsies and liver explants were available in 23 patients, whole livers only in 11 cases, and biopsies only in 11 cases. An etiologic diagnosis was established in 16 cases (36%). A further 3 cases (7%) were associated with aplastic anemia. Established etiologies included drug reactions (n = 7); autoimmune hepatitis, type 2 (n = 3); halothane hepatitis (n = 1); ischemia/hypotension (n = 1); mushroom poisoning (n = 1); mitochondrial disorder (n = 1); hemophagocytic lymphohistiocytosis (n = 1); and adenoviral hepatitis (n = 1). The extent of necrosis on liver biopsy correlated poorly with that in liver explants (mean difference, 32% +/- 23.8%). Almost all cases could be classified into one of 2 broad patterns of necrosis, namely, (1) zonal coagulative necrosis or (2) panlobular (nonzonal) necrosis. These patterns differed significantly with respect to several clinical parameters including sex ratio, peripheral blood white cell count, serum aspartate transaminase and alanine transaminase, conjugated bilirubin, and alkaline phosphatase levels. Livers with panlobular necrosis showed a spectrum of histopathologic findings that included central venulitis (76%), lymphocytic infiltration of large duct/gallbladder epithelium (54%), and syncytial giant cell transformation (18%). These features were not seen in livers with zonal coagulative necrosis which frequently showed prominent steatosis (91%). Both patterns of necrosis frequently showed ductular proliferation (100%) and cholangiolitis (80%). The diagnostic yield of ancillary studies (histochemistry, immunohistochemistry, and electron microscopy) was very low (<1%). The small proportion of cases with etiologic diagnoses precluded correlation of clinical and histopathological parameters with specific etiologies. In summary, this study describes the spectrum of changes seen in massive and submassive necrosis in children and identifies clinical features that might differentiate between 2 broad patterns of necrosis.

Population-based surveillance for acute liver failure

OBJECTIVES

Most U.S. studies of acute liver failure (ALF) patients have been conducted at tertiary care liver transplantation centers. The aim of this study was to conduct population-based surveillance for ALF.

METHODS

We conducted population-based surveillance for ALF within the 8 counties comprising Metropolitan Atlanta between November 2000 and October 2004. ALF cases were defined as the presence of coagulopathy, any grade of hepatic encephalopathy within 26 wk of illness onset, and no history of underlying liver disease. A questionnaire was administered and medical records were reviewed to determine clinical features, etiologies, and outcomes.

RESULTS

A total of 65 cases were enrolled, yielding an annualized incidence for all causes of ALF of 5.5 (95% CI 4.3-7.0) per million. Acetaminophen (APAP)-related ALF was the most common (41%) etiology in adults while ALF of undetermined etiology was most common (38%) in children, followed by APAP-related ALF (25%). Unintentional APAP overdose was the most common type (61%) of APAP-related cause. Blacks were more likely than other races to have ALF of undetermined etiology (32%vs 11%). Overall mortality was 40%, with 27 (42%) surviving with supportive care alone and 8 (12%) requiring orthotopic liver transplantation.

CONCLUSIONS

Our population-based study suggests approximately 1,600 ALF cases occur in the United States each year. Consistent with findings from studies conducted exclusively at liver transplantation centers, APAP-related ALF was the most common etiology. Increased awareness of APAP-related ALF in the medical community may limit future cases. More research is warranted into ALF of undetermined etiology, especially in children.

Paediatric acute liver failure and transplantation: The University of Essen experience

To report our experience with 17 children who underwent a liver transplantation (LT) for acute liver failure (ALF). All LT procedures (deceased and living donor) were offered. Since 2003 Molecular Adsorbents Recycling System (MARS) was proposed as bridging procedure. We monitored the perioperative course and the short- and long-term outcomes. All children developed pretransplant hepatic encephalopathy (mostly grades II and III); six needed ventilator support and three haemodialysis. Median PELD/MELD score was 30. MARS was used in five children with poor pretransplant prognostic factors: all five survived the LT without sequelae. We performed 13 deceased donor LT (seven whole, five split and onr reduced) and four left lateral LDLT. Postoperative complications were observed in 10 children, requiring re-operation in seven. Two children developed irreversible neurological disorders. After a median follow up of 45 months, 16 children are still alive. About 1- and 5-year cumulative patient survival rates are 94% with a corresponding graft survival of 88% and 81%, respectively. The combination of experienced paediatric ICU management, the application of new liver support devices, and the capacity to offer both living and deceased donor transplant alternatives in a timely fashion represent the best formula to achieve optimal results in children with ALF.

Issues unique to pediatric liver transplantation

Liver transplantation in pediatrics has become an accepted modality of treatment in end-stage liver disease and irreversible acute liver failure. Biliary atresia is the most common indication requiring liver transplantation in children. The diagnosis and causes of acute liver failure in children differ from those in adults. Growth and development require special consideration in children. Regular surveillance of Epstein-Barr virus by polymerase chain reaction and appropriate therapy may reduce the incidence of post-transplant lymphoproliferative disease after transplantation. Adherence to the prescribed medical regimen is essential for good graft function. A multidisciplinary approach is the key to success in liver transplantation in children.

Predictors of clinical outcome in children undergoing orthotopic liver transplantation for acute and chronic liver disease

The current United Network for Organ Sharing (UNOS) policy is to allocate liver grafts to pediatric patients with chronic liver disease based on the pediatric end-stage liver disease (PELD) scoring system, while children with fulminant hepatic failure may be urgently listed as Status 1a. The objective of this study was to identify pre-transplant variables that influence patient and graft survival in those children undergoing LTx (liver transplantion) for FHF (fulminant hepatic failure) compared to those patients transplanted for extrahepatic biliary atresia (EHBA), a chronic form of liver disease. The UNOS Liver Transplant Registry was examined for pediatric liver transplants performed for FHF and EHBA from 1987 to 2002. Variables that influenced patient and graft survival were assessed using univariate and multivariate analysis. Kaplan-Meier analysis of FHF and EHBA groups revealed that 5 year patient and graft survival were both significantly worse (P < 0.0001) in those patients who underwent transplantation for FHF. Multivariate analysis of 29 variables subsequently revealed distinct sets of factors that influenced patient and graft survival for both FHF and EHBA. These results confirm that separate prioritizing systems for LTx are needed for children with chronic liver disease and FHF; additionally, our findings illustrate that there are unique sets of variables which predict survival following LTx for these two groups.

Acute liver failure in children: the first 348 patients in the pediatric acute liver failure study group

OBJECTIVES

To determine short-term outcome for children with acute liver failure (ALF) as it relates to cause, clinical status, and patient demographics and to determine prognostic factors.

STUDY DESIGN

A prospective, multicenter case study collecting demographic, clinical, laboratory, and short-term outcome data on children from birth to 18 years with ALF. Patients without encephalopathy were included if the prothrombin time and international normalized ratio remained > or = 20 seconds and/or >2, respectively, despite vitamin K. Primary outcome measures 3 weeks after study entry were death, death after transplantation, alive with native liver, and alive with transplanted organ.

RESULTS

The cause of ALF in 348 children included acute acetaminophen toxicity (14%), metabolic disease (10%), autoimmune liver disease (6%), non-acetaminophen drug-related hepatotoxicity (5%), infections (6%), other diagnosed conditions (10%); 49% were indeterminate. Outcome varied between patient sub-groups; 20% with non-acetaminophen ALF died or underwent liver transplantation and never had clinical encephalopathy.

CONCLUSIONS

Causes of ALF in children differ from in adults. Clinical encephalopathy may not be present in children. The high percentage of indeterminate cases provides an opportunity for investigation.

Pediatric liver transplantation

In the past two decades, pediatric liver transplantation has become the state-of-the-art operation with anticipated success and limited mortality. The future success of pediatric liver transplantation will require thoughtful solutions to the delicate balance of risk to donors and recipients, the complex needs of the acute postoperative patient, and the long-term challenges of chronic immunosuppression in these previously unsalvageable patients.

Acute liver failure in children

Acute liver failure (ALF) is a rare but devastating illness. Specific therapy to promote liver recovery is often not available, and the underlying cause of the liver failure is often unknown. This article examines current knowledge of the epidemiology, pathobiology, and treatment of ALF in children and identifies potential gaps in this knowledge for future study.

Characterization of acute liver failure and development of a continuous risk of death staging system in children

BACKGROUND/AIMS

Acute liver failure (ALF) in children has been associated with an overall mortality of approximately 70% in the pretransplant era and 50-80% survival in those undergoing orthotopic liver transplantation. There is currently no system for staging severity of ALF in children. The aim of this study was to characterize pediatric ALF in a tertiary hospital and to derive a scoring system to stratify severity of ALF based on predicted mortality.

METHODS

Prospective data collection of 81 children from December 1993-2003 who presented with ALF. Data recorded included peak laboratory values, clinical characteristics, and survival.

RESULTS

Transplant-free survival was 56% with overall survival including those undergoing OLT of 72%. Transplantation rate was 22% with transplant survival of 72%. Of the peak laboratory values analyzed, total bilirubin, prothrombin time/INR, and ammonia were the most predictive of death or a need for liver transplant. A simple risk staging system was developed based on the ability of these three laboratory measurements to predict mortality.

CONCLUSIONS

The survival in pediatric ALF has improved in recent years. Risk staging for ALF could potentially be used in clinical research for risk-adjusted outcomes analysis and to help stratify patients for clinical studies according to mortality risk.

Transplantation for acute liver failure in children

We reviewed the clinical data of 30 children-hospitalized for acute liver failure in the last 6 years. Ten patients were not listed for liver transplantation OLTX. Their clinical conditions gradually improved and they are all alive without deficit. Among 20 patients listed, 15 underwent urgent OLTX. Two children died on the waiting list and three were suspended from waiting list after few days because of improvement. Survival according to age class was analyzed dividing the patients into two groups: A, age 1 year or less versus B, age between 1 and 16 years. The patient survival was 86% at 6 months and 61% both at 1 and 2 years. Survival at 6 months and 1 and 2 years was 88%, 67%, and 45% for the patients in group A and 83%, 83%, and 83% for the patients in group B (P = NS). Observing graft-to-recipient weight ratio and donor-to-recipient weight ratio most patients received an optimal sized graft. The split-liver technique is considered the preferred method of liver transplantation even in the pediatric patients with acute liver failure; especially in the setting of a cooperative system in which all livers that are suitable for split-liver transplantation are shared between centers. In order to have the best chance for survival, children with acute liver failure should be referred as soon as possible to an highly specialized pediatric liver transplantation center that can offer all the treatment modalities that are currently available.

Resolution of hypophosphatemia is associated with recovery of hepatic function in children with fulminant hepatic failure

Fulminant hepatic failure (FHF) is a rare but often fatal disease in children. Clinical and laboratory predictors of liver regeneration and recovery, however, have not been well established. We hypothesized that hypophosphatemia may indicate recovery of liver synthetic function in children with FHF. We retrospectively reviewed the medical records of children with FHF who were admitted to UCLA and recovered hepatic function either spontaneously or by liver transplantation (LTx). Serum phosphate (Ph) and prothrombin time or international normalized ratio (INR) were compared over the patient's clinical course. Records of 39 children who spontaneously recovered experienced profound hypophosphatemia that resolved as liver synthetic function improved. Similar patterns were seen in the 84 children who recovered after LTx. We found that hypophosphatemia precedes the recovery of liver synthetic function in children with FHF who recovered with or without transplantation, and that Ph levels return to normal as liver synthetic function improves. These data suggest that hypophosphatemia may be a useful laboratory indicator of recovering liver function in children with FHF.

Etiology, outcome and prognostic indicators of childhood fulminant hepatic failure in the United kingdom

OBJECTIVE

To study the etiology, outcome and prognostic indicators in children with fulminant hepatic failure in the United Kingdom.

DESIGN

Retrospective review of all patients <17 years with fulminant hepatic failure from 1991 to 2000. Fulminant hepatic failure was defined as presence of coagulopathy (prothrombin time >24 seconds or International Normalized Ratio >2.0) with or without hepatic encephalopathy within 8 weeks of the onset of symptoms.

SETTING

Liver Unit, Birmingham Children's Hospital, United Kingdom.

RESULTS

Ninety-seven children (48 male, 49 female; median age, 27 months; range, 1 day-192.0 months) were identified with fulminant hepatic failure. The etiologies were: 22 metabolic, 53 infectious, 19 drug-induced, and 3 autoimmune hepatitis. The overall survival rate was 61%. 33% (32/97) recovered spontaneously with supportive management. Fifty-five children were assessed for liver transplantation. Four were unstable and were not listed for liver transplantation; 11 died while awaiting liver transplantation. Liver transplantation was contraindicated in 10 children. Of the 40 children who underwent liver transplantation, 27 survived. Children with autoimmune hepatitis, paracetamol overdose or hepatitis A were more likely to survive without liver transplantation. Children who had a delay between the first symptom of liver disease and the onset of hepatic encephalopathy (median, 10.5 days versus 3.5 days), higher plasma bilirubin (299 micromol/L versus 80 micromol/L), higher prothrombin time (62 seconds versus 40 seconds) or lower alanine aminotransferase (1288 IU/L versus 2929 IU/L) levels on admission were more likely to die of fulminant hepatic failure or require liver transplantation (P < 0.05). On multivariate analysis, the significant independent predictors for the eventual failure of conservative therapy were time to onset of hepatic encephalopathy >7 days, prothrombin time >55 seconds and alanine aminotransferase </=2384 IU/L on admission.

CONCLUSIONS

Children with fulminant hepatic failure with severe coagulopathy, lower alanine aminotransferase on admission and prolonged duration of illness before the onset of hepatic encephalopathy are more likely to require liver transplantation. Early referral to a specialized center for consideration of liver transplantation is vital.