Acute-on-chronic liver failure in children with biliary atresia awaiting liver transplantation

The Outcome of a Centralization Program in Biliary Atresia: Twenty Years and Beyond

OBJECTIVE

Biliary atresia is a rare disease and reported outcomes of surgical management, typically a Kasai portoenterostomy (KPE), vary considerably across the world. Centralization has been proposed to improve this.

BACKGROUND

A national centralization program was started in January 1999, involving 3 English units with colocated liver transplant facilities. As the program has now reached the 20-year point, the main aim was to update outcome statistics and identify trends.

METHODS

Prospective registry and database. The main measures of outcome were (1) time to KPE, (2) clearance of jaundice (CoJ), defined as reaching a bilirubin value of <20 µmol/L (≈1.5 mg/dL), and (3) actuarial native liver survival and overall survival (OS). Data are quoted as median (interquartile range) and nonparametric statistical comparison used with P <0.05 regarded as statistically significant.

RESULTS

A total of 867 infants were born with biliary atresia and managed between January 1999 and December 2019. Death occurred without intervention (n = 10, 1.1%) or were subject to primary transplant (n = 26, 3.0%); leaving 831 (95.9%) infants who underwent KPE at a median age of 51 (interquartile range: 39-64) days. Age at KPE reduced over the period ( P = 0.0001) becoming 48 (35-57) days in the last 5-year era. CoJ was achieved in 505/831 (60.6%), also increasing over the period ( P = 0.002). Forty-two (5.0%) died post-KPE and 384 were transplanted, leaving 405 alive with their native livers at the last follow-up. Of the 412 children transplanted, there were 23 (5.6%) deaths, leaving 387 alive. Five-year and 10-year native liver survivals were 51.3% (95% CI: 54.8-47.8) and 46.5% (95% CI: 50.1-42.9) and OSs were 91.5% (95% CI 93.2-89.4) and 90.5% (95% CI 92.3-88.2%), respectively.

CONCLUSIONS

There have been continued improvements in efficiency over the period of centralization with a significant reduction in time to KPE and improved CoJ after KPE. OS in this disease remains >90%.

Postoperative outcomes of acute-on-chronic liver failure in infants and children with biliary atresia

INTRODUCTION

Acute-on-chronic liver failure (ACLF) is associated with increased mortality and morbidity in patients with biliary atresia (BA). Data on impact of ACLF on postoperative outcomes, however, are sparse.

METHOD

We performed a retrospective analysis of patients with BA aged <18 years who underwent LT between 2011 and 2021 at our institution. ACLF was defined using the pediatric ACLF criteria: ≥1 extra-hepatic organ failure in children with decompensated cirrhosis.

RESULTS

Of 107 patients (65% female; median age 14 [9-31] months) who received a LT, 13 (12%) had ACLF during the index admission prior to LT. Two (15%) had Grade 1; 4 (30%) had Grade 2; and 7 (55%) had Grade ≥3 ACLF. ACLF cohort was younger at time of listing (5 [4-8] vs. 9 [6-24] months; p < .001) and at LT (8 [8-11] vs. 16 [10-40] months, p < .001) compared to no-ACLF group. Intraoperatively, ACLF patients had higher blood loss (40 [20-53] vs. 10 [6-19] mL/kg; p < .001) and blood transfusion requirements (33 [21-69] vs. 18 [7-25] mL/kg; p = .004). Postoperatively, they needed higher vasopressor support (31% vs. 10.6%; p = .04) and had higher total hospital length of stay (106 [45-151] vs. 13 [7-30] days; p = .023). Rate of return to the operating room, hospital readmission rates, and 1-year post-LT survival rates were comparable between the groups.

CONCLUSION

Despite higher perioperative complications, survival outcomes for ACLF in BA after LT are favorable and comparable to those without ACLF. These encouraging data reiterate prioritization during organ allocation of these critically ill children for LT.

Pediatric Acute-on-Chronic Liver Failure

Acute-on-chronic liver failure (ACLF) is characterized by an acute hepatic insult happening in a patient with underlying cirrhosis with compromised hepatic reserve leading to development of systemic inflammation, sepsis, and organ failure resulting in poor outcome in majority. While Asia Pacific Association for Study of Liver Diseases (APASL) emphasizes on early diagnosis before development of organ failure, European Association for Study of Liver Diseases (EASL) mandates the presence of organ failures to define ACLF. There is a lack of consensus definition of pediatric ACLF although recent APASL guidelines have tried to address the issue. While Wilson disease (WD) and autoimmune hepatitis (AIH) are the most common cause of underlying cirrhosis in children, acute viral hepatitis and flares of WD and AIH are the commonest acute precipitating events. Poor outcomes [death and liver transplantation (LT)] ranging from 19 to 59% have been reported. Prognosis in pediatric ACLF is usually better than that in adults due to greater proportion of treatable etiologies, lesser organ failures, comorbidities and better hepatic reserves. APASL ACLF Research Consortium (AARC) score more than or equal to 11 is predictive of poor 28-90 d mortality. Treatment of pediatric ACLF relies mainly on prompt diagnosis and medical management of a potentially treatable etiology of underlying cirrhosis. Bridging therapies, especially high volume plasma exchange can be initiated early as a bridge to LT or native liver recovery. Those with no improvement in 4-7 d should undergo LT before development of sepsis or multi-organ failure.

Respiratory problems associated with liver disease in children

Respiratory manifestations of chronic liver disease have a profound impact on patient clinical outcomes. Certain conditions within paediatric liver disease have an associated respiratory pathology. This overlap between liver and respiratory manifestations can result in complex challenges when managing patients and requires clinicians to be able to recognise when referral to specialists is required. While liver transplantation is at the centre of treatment, it opens up further potential for respiratory complications. It is established that these complications place patients at risk of longer stays in hospital and reduced survival. Additionally, late post-transplant complications can occur, including post-transplant lymphoproliferative disease and immunosuppression-induced interstitial lung disease. Although rare, it is important for clinicians to recognise these conditions to allow for prompt management. Finally, as liver disease progresses in children, respiratory complications can occur. Hepatopulmonary syndrome can occur in the context of portal hypertension, resulting in increased mortality and poorer quality of life for patients. Another consequence is portopulmonary hypertension, which can be associated with poor survival. Failure to recognise these complications in children may result in poorer outcomes and therefore it is vital that clinicians can establish when referral to a paediatric respiratory medicine specialist is required.

Hepatic Encephalopathy in Children

Hepatic encephalopathy, characterized by mental status changes and neuropsychiatric impairment, is associated with chronic liver disease as well as acute liver failure. In children, its clinical manifestations can be challenging to pinpoint. However, careful assessment for the development of hepatic encephalopathy is imperative when caring for these patients as progression of symptoms can indicate impending cerebral edema and systemic deterioration. Hepatic encephalopathy can present with hyperammonemia, but it is important to note that the degree of hyperammonemia is not indicative of severity of clinical manifestations. Newer forms of assessment are undergoing further research, and include imaging, EEG and neurobiomarkers. Mainstay of treatment currently includes management of underlying cause of liver disease, as well as reduction of hyperammonemia with either enteral medications such as lactulose and rifaximin, or even with extracorporeal liver support modalities.

Transient elastography and von Willebrand factor as predictors of portal hypertension and decompensation in children

Background & Aims

Von Willebrand factor antigen (vWFAg), a protein measured to test the level of vWF released from the vascular endothelium has gained much attention as a marker for portal hypertension (PHT) severity. The objectives of this study were to investigate the use of vWFAg as a biomarker along with liver and spleen stiffness measurements by transient elastography as potential predictors of clinically significant varices (CSV), variceal bleeding (VB) and decompensation in children with PHT.

Methods

This observational prospective cohort study included 117 children (median age 10 [IQR 6-14] years) who underwent oesophagogastroduodenoscopy between January'2012 to November'2021 and a validation group of 33 children who underwent the same procedure between December'2021 to March'2023. Measurements of vWFAg and glycoprotein Ib binding activity of VWF (GPIbR) were available in 97 patients in the study group and in all patients in the validation group.Results: vWFAg and GPIbR were significantly higher in children with CSV (223 IU/dl and 166 IU/dl; p = 0.015 and p = 0.04, respectively) and VB (218 IU/dl and 174 IU/dl; p = 0.077 and p = 0.03, respectively) than in those without CSV or VB, respectively. Ninety-six patients had liver and spleen stiffness measurements. Spleen stiffness was significantly higher in patients with CSV compared to those without CSV (p = 0.003). In a chronic liver disease subgroup, a predictive scoring tool based on vWFAg, GPIbR, platelet count, and spleen/liver stiffness measurements could predict CSV with an AUROC of 0.76 (p = 0.04).

Conclusions

This study suggests the predictive value of vWF for CSV and VB increases when combined with spleen stiffness, with AUROCs of 0.88 and 0.82, respectively. Hence, a combination of biomarkers could assist clinicians in diagnosing CSV, preventing unnecessary invasive procedures.

Impacts and implications

Surveillance endoscopies in children with portal hypertension (PHT) have their own risks and non-invasive markers, such as von Willebrand factor antigen, glycoprotein Ib binding activity of VWF (GPIbR), and transient elastography could be used to predict clinically significant varices, variceal bleeding and disease compensation in children with PHT. Such non-invasive markers for PHT and varices are lacking in the paediatric population. The results show that von Willebrand factor and GPIbR along with transient elastography can be used to formulate a scoring system which can be used as a clinical tool by paediatric hepatologists to monitor the progression of PHT and risk of bleeding, and hence to stratify the performance of invasive endoscopic procedures under general anaesthesia. However, there is a need to validate the scoring system in children with portal vein thrombosis and for hepatic decompensation in a multi-centre registry in the future.

Consensus document on acute-on-chronic liver failure (ACLF) established by the Mexican Association of Hepatology

Acute-on chronic liver failure (ACLF) has been an intensively debated topic mainly due to the lack of a unified definition and diagnostic criteria. The growing number of publications describing the mechanisms of ACLF development, the progression of the disease, outcomes and treatment has contributed to a better understanding of the disease, however, it has also sparked the debate about this condition. As an attempt to provide medical professionals with a more uniform definition that could be applied to our population, the first Mexican consensus was performed by a panel of experts in the area of hepatology in Mexico. We used the most relevant and impactful publications along with the clinical and research experience of the consensus participants. The consensus was led by 4 coordinators who provided the most relevant bibliography by doing an exhaustive search on the topic. The entire bibliography was made available to the members of the consensus for consultation at any time during the process and six working groups were formed to develop the following sections: 1.- Generalities, definitions, and criteria, 2.- Pathophysiology of cirrhosis, 3.- Genetics in ACLF, 4.- Clinical manifestations, 5.- Liver transplantation in ACLF, 6.- Other treatments.

Acute-on-chronic liver failure before liver transplantation does not impact post-transplant survival in children with biliary atresia

Acute-on-chronic liver failure (ACLF) occurs in children with biliary atresia (BA) awaiting liver transplantation (LT). However, data on transplant outcomes in ACLF are limited. Our aim was to characterize ACLF and determine its effect on transplant outcome and resource utilization. Using a linkage of the Scientific Registry of Transplant Recipients and Pediatric Health Information System, we identified children with BA between 3 months and 18 years at the time of listing who received a transplant from 2003 to 2018 and were hospitalized while waiting. ACLF was defined by the presence of at least 1 extra-hepatic organ failure during a pre-LT hospitalization. In all, 1044 patients (58% female, median age at listing 7.0 months IQR 5.0-14.0) were included. Thirty-four percent (351/1044) of the patients had at least 1 ACLF hospitalization. Patients with ACLF had longer waitlist times (114 [54-231] vs. 81 [35-181] days, p < 0.001), and were more likely to be listed as Status 1 (8% vs. 4%, p = 0.02). Pre-LT resource utilization was significantly higher in ACLF patients. There were no differences in mortality at 30 days (ACLF 3% vs. No ACLF 2%, p = 0.17), 90 days (ACLF 3% vs. No ACLF 2%, p = 0.24), 1 year (ACLF 3% vs. No ACLF 2%, p =0.23), 3 years (ACLF 4% vs. No ACLF 3%, p = 0.58), or 5 years (ACLF 5% vs. No ACLF 4%, p = 0.38) after LT. ACLF status was not associated with increased post-transplant mortality (adjusted HR 1.51, 95% CI 0.76-3.0, p =0.25). ACLF is an important morbidity in children with BA awaiting LT as it is associated with higher resource utilization and longer waitlist times. Further studies are needed to help understand the spectrum of ACLF and better prioritize critically ill children awaiting LT, as our study shows successful post-LT outcomes in children with BA and ACLF.

Neonatal Hepatic Myeloid Progenitors Expand and Propagate Liver Injury in Mice

BACKGROUND

Biliary atresia (BA) is a progressive pediatric inflammatory disease of the liver that leads to cirrhosis and necessitates liver transplantation. The rapid progression from liver injury to liver failure in children with BA suggests that factors specific to the perinatal hepatic environment are important for disease propagation. Hematopoietic stem and progenitor cells (HSPCs) reside in the fetal liver and are known to serve as central hubs of inflammation. We hypothesized that HSPCs are critical for the propagation of perinatal liver injury (PLI).

METHODS

Newborn BALB/c mice were injected with rhesus rotavirus (RRV) to induce PLI or with PBS as control. Livers were compared using histology and flow cytometry. To determine the effects of HSPCs on PLI, RRV-infected neonatal mice were administered anti-CD47 and anti-CD117 to deplete HSPCs.

RESULTS

PLI significantly increased the number of common myeloid progenitors and the number of CD34⁺ hematopoietic progenitors. Elimination of HSPCs through antibody-mediated myeloablation rescued animals from PLI and significantly increased survival (RRV+isotype control 36.4% vs. RRV+myeloablation 77.8%, Chi-test = 0.003).

CONCLUSIONS

HSPCs expand as a result of RRV infection and propagate PLI. Targeting of HSPCs may be useful in preventing and treating neonatal inflammatory diseases of the liver such as BA.

Efficacy and Safety of Endoscopic Primary Prophylaxis of Bleeding in Children With High-Risk Gastroesophageal Varices

OBJECTIVES

Primary prophylaxis of bleeding is debated in children with gastroesophageal varices; one of the reasons is the limited number of studies concerning its efficacy and safety. We report our experience with endoscopic primary prophylaxis.

METHODS

From 2006 to 2019, 145 children (median age, 3.5 years; cirrhosis, n = 116) with high-risk gastroesophageal varices underwent primary prophylaxis (banding, n = 114; sclerotherapy n = 31, primarily in smaller children).

RESULTS

We observed the eradication of varices in 93% of children after a mean of 6 months, at least one recurrence of varices in 45% after eradication, and gastrointestinal bleeding in 17% of children. Irrespective of the cause of portal hypertension, grade 3 esophageal varices, presence of gastric varices along the cardia and a lower composite score of endoscopic severity were associated with a worse probability of eradication, a longer time to eradication and a lower risk of a first recurrence and of bleeding following the procedure, respectively. Ten-year probabilities of overall survival and of bleeding-free survival were 95% and 75%, respectively.

CONCLUSIONS

Endoscopic primary prophylaxis of variceal bleeding is reasonably effective and safe in children with high-risk gastroesophageal varices. Worse results are observed in children with more advanced endoscopic features. This pleads for endoscopic screening in children with portal hypertension and early detection of varices warranting primary prophylaxis.

Rescue venovenous extracorporeal membrane oxygenation for the deterioration of acute respiratory distress syndrome in pediatric liver transplantation

BACKGROUND

Twenty percent of pediatric patients with BA develop ACLF with increased mortality while awaiting LT. Respiratory complications are common in pediatric ACLF and are associated with increased morbidity and mortality. ARDS is the most severe manifestation of acute respiratory failure with considerable risk of mortality.

METHODS

A 5-month-old girl with post-Kasai BA preoperatively experienced ARDS from RSV infection while awaiting LT. She developed decompensated liver failure with shock, acute kidney injury, coagulopathy, and pulmonary hemorrhage after several episodes of sepsis over the course of 1 month in the PICU. At this stage, RSV was not detected in the patient's tracheal aspirate by real-time polymerase chain reaction. She underwent living donor LT to manage her pre-existing critical state. Following reperfusion during LT, her pre-existing ARDS rapidly deteriorated, which was alleviated by intraoperative VV ECMO.

RESULTS

Severe respiratory acidosis improved rapidly following ECMO, and LT was completed uneventfully. The patient was successfully weaned off ECMO on POD 3.

CONCLUSIONS

This is the first pediatric case rescued by the intraoperative application of ECMO during LT. Our case and cumulative evidence suggest that VV ECMO can serve as rescue therapy for perioperative refractory respiratory failure in pediatric LT.

Status 1B designation does not adequately prioritize children with acute-on-chronic liver failure for liver transplantation

Acute-on-chronic liver failure (ACLF) is an acute decompensation of chronic liver disease leading to multiorgan failure and mortality. The objective of this study was to evaluate characteristics and outcomes of children with ACLF who are at the highest priority for liver transplantation (LT) on the United Network for Organ Sharing (UNOS) database-listed as status 1B. The characteristics and outcomes of 478 children with ACLF listed as status 1B on the UNOS LT waiting list from 2007-2019 were compared with children with similar or higher priority listing for transplant: 929 with acute liver failure (ALF) listed as status 1A and 808 with metabolic diseases and malignancies listed as status 1B (termed "non-ACLF"). Children with ACLF had comparable rates of cumulative organ failures compared with ALF (45% vs. 44%; p > 0.99) listings, but higher than non-ACLF (45% vs. 1%; p < 0.001). ACLF had the lowest LT rate (79%, 84%, 95%; p < 0.001), highest pre-LT mortality (20%, 11%, 1%; p < 0.001), and longest waitlist time (57, 3, 56 days; p < 0.001), and none recovered without LT (0%, 4%, 1%; p < 0.001). In survival analyses, ACLF was associated with an increased adjusted hazard ratio (HR) for post-LT mortality (HR, 1.50 vs. ALF [95% confidence interval, CI, 1.02-2.19; p = 0.04] and HR, 1.64 vs. non-ACLF [95% CI, 1.15-2.34; p = 0.01]). ACLF has the least favorable waitlist and post-LT outcomes of all patients who are status 1A/1B. Increased prioritization on the LT waiting list may offer children with ACLF an opportunity for enhanced outcomes.

Acute-on-chronic liver failure: A 20-year retrospective review of a tertiary paediatric liver centre

AIM

Acute-on-chronic liver failure (ACLF) is an acute deterioration of pre-existing chronic liver disease related to a precipitating event. We characterised paediatric ACLF at Birmingham Children's Hospital (BCH) utilising European Association of Liver Disease CLIF criteria, including prevalence, triggers and outcomes.

METHODS

All BCH patients from 2000 to 2020 with CLD who underwent initial liver transplant or died on the transplant waiting list or whilst too unwell to be listed were reviewed.

RESULTS

From 2000 to 2020, 24 (4%) children with ACLF were identified. Death occurred in 18 (75%). Transplant occurred in 9 (36%), 3 of which died. ACLF triggers were sepsis organism negative 11 (46%), sepsis organism positive 8 (33%) and GI bleed 5 (17%). Bilirubin at the time of transplant/death in those with ACLF who lived compared with those who died was 529 umol/L (381) versus 665 (210) (p=0.38), creatinine 138 umol/L (147) versus 67 (46) (p=0.41), PT 33 sec (14) versus (32 (15) (p = 0.72), Grade 3, 4 hepatic encephalopathy 1 (17%) versus 10 (56%) (p = 0.17), vasopressor use 1 (17%) versus 17 (94%) (p = 0.001) and ventilation 3 (50%) versus 17 (94%) (p = 0.035).

CONCLUSION

Acute-on-chronic liver failure whilst infrequent has high rates of mortality. The use of vasopressors and ventilation is more frequent in those who die from ACLF.

A Model for Early Endoscopic Detection of High-Risk Gastroesophageal Varices in Children With Biliary Atresia

OBJECTIVE

In children with biliary atresia and portal hypertension, progression to gastroesophageal varices carrying a risk of bleeding depends on age, total serum bilirubin concentration and initial endoscopic features. We report an attempt to use these factors for early detection of high-risk varices (HRVs).

METHODS

Based on different combinations of these factors, a model was set to estimate the probabilities of emergence of HRVs at various time intervals. A 10% probability was chosen to set the date of the next endoscopy in children who did not display HRVs initially. A total of 113 children without HRVs who underwent their first endoscopy before age 8 in 2013-2020 were included. A comparison was made with children seen during the period 1990-2012 when this model was not used.

RESULTS

In all, 65 of the 113 children underwent one to five additional endoscopies at dates set according to the model. The emergence of HRVs was recorded in 22 children after a mean interval of 14 months and was managed by endoscopic primary prophylaxis in all but one who underwent liver transplantation. Three other children bled before the next planned endoscopy. Compared with 175 children of the same age ranges without HRVs in the period 1990-2012, the use of the model was associated with a faster detection of HRVs with a lower number of endoscopic procedures (P  = 0.0022 and P  = 0.023, respectively).

CONCLUSION

The results suggest that the model reported may be a useful tool for the early detection of HRVs to allow primary prophylaxis of bleeding.

Variability of Care and Access to Transplantation for Children with Biliary Atresia Who Need a Liver Replacement

Background & Aims: Biliary atresia (BA) is the commonest single etiology indication for liver replacement in children. As timely access to liver transplantation (LT) remains challenging for small BA children (with prolonged waiting time being associated with clinical deterioration leading to both preventable pre- and post-transplant morbidity and mortality), the care pathway of BA children in need of LT was analyzed—from diagnosis to LT—with particular attention to referral patterns, timing of referral, waiting list dynamics and need for medical assistance before LT. Methods: International multicentric retrospective study. Intent-to-transplant study analyzing BA children who had indication for LT early in life (aged < 3 years at the time of assessment), over the last 5 years (2016−2020). Clinical and laboratory data of 219 BA children were collected from 8 transplant centers (6 in Europe and 2 in USA). Results: 39 patients underwent primary transplants. Children who underwent Kasai in a specialist -but not transplant- center were older at time of referral and at transplant. At assessment for LT, the vast majority of children already were experiencing complication of cirrhosis, and the majority of children needed medical assistance (nutritional support, hospitalization, transfusion of albumin or blood) while waiting for transplantation. Severe worsening of the clinical condition led to the need for requesting a priority status (i.e., Peld Score exception or similar) for timely graft allocation for 76 children, overall (35%). Conclusions: As LT currently results in BA patient survival exceeding 95% in many expert LT centers, the paradigm for BA management optimization and survival have currently shifted to the pre-LT management. The creation of networks dedicated to the timely referral to a pediatric transplant center and possibly centralization of care should be considered, in combination with implementing all different graft type surgeries in specialist centers (including split and living donor LTs) to achieve timely LT in this vulnerable population.

Proceedings of ESPGHAN Monothematic Conference 2020: "Acute Liver Failure in Children": Diagnosis and Initial Management

OBJECTIVES

The Hepatology Committee of the European Society for Pediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) aims to educate pediatric gastroenterologists, members of ESPGHAN and professionals from other specialties promoting an exchange of clinical expertise in the field of pediatric hepatology. Herewith we have concentrated on detailing the recent advances in acute liver failure in infants and children.

METHODS

The 2020 ESPGHAN monothematic three-day conference on pediatric hepatology disease, entitled "acute liver failure" (ALF), was organized in Athens, Greece. ALF is a devastating disease with high mortality and most cases remain undiagnosed. As knowledge in diagnosis and treatment of ALF in infants and children has increased in the past decades, the objective was to update physicians in the field with the latest research and developments in early recognition, curative therapies and intensive care management, imaging techniques and treatment paradigms in these age groups.

RESULTS

In the first session, the definition, epidemiology, various causes of ALF, in neonates and older children and recurrent ALF (RALF) were discussed. The second session was dedicated to new aspects of ALF management including hepatic encephalopathy (HE), coagulopathy, intensive care interventions, acute on chronic liver failure, and the role of imaging in treatment and prognosis. Oral presentations by experts in various fields are summarized highlighting key learning points.

CONCLUSIONS

The current report summarizes the major learning points from this meeting. It also identifies areas where there is gap of knowledge, thereby identifying the research agenda for the near future.

Hepatorenal syndrome in acute-on-chronic liver failure with acute kidney injury: more questions requiring discussion

In cirrhosis with ascites, hepatorenal syndrome (HRS) is a specific prerenal dysfunction unresponsive to fluid volume expansion. Acute-on-chronic liver failure (ACLF) comprises a group of clinical syndromes with multiple organ failure and early high mortality. There are differences in the characterization of ACLF between the Eastern and Western medical communities. Patients with ACLF and acute kidney injury (AKI) have more structural injuries, contributing to confusion in diagnosing HRS-AKI. In this review, we discuss progress in the pathogenesis, diagnosis, and management of HRS-AKI, especially in patients with ACLF. Controversy regarding HRS-AKI in ACLF and acute liver failure, hepatic carcinoma, shock, sepsis, and chronic kidney disease is also discussed. Research on the treatment of HRS-AKI with ACLF needs to be more actively pursued to improve disease prognosis.

Acute-on-chronic liver failure in children

Although various complex definitions of acute-on-chronic liver failure (ACLF) have been suggested in relation to adult patients, there is currently no universal definition of the syndrome in pediatric patients. In simplified terms, ACLF is characterized by the acute deterioration of the liver functions due to the effects of a precipitating factor on the basis of a chronic liver disease. Acute events and underlying liver diseases are very different in children from those seen in adults. Moreover, acute events and underlying chronic liver diseases vary among geographical regions, although it seems that the most common such diseases and acute events are autoimmune hepatitis, Wilson's disease, and their flares. ACLF is associated with a poor prognosis. While no scoring systems have been developed to predict the prognosis for children with ACLF, modified versions of the Asian Pacific Association for the Study of the liver's acute-on-chronic liver failure scoring system and the Chronic Liver Failure-Sequential Organ Failure Assessment criteria can be used in children until specific and validated scoring systems are available. Aside from liver transplantation, there is no proven treatment for ACLF. Thus, the early recognition of ACLF prior to the development of extrahepatic organ failure is important.

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.

METABOLIC AND NUTRITIONAL REPERCUSSIONS OF LIVER DISEASE ON CHILDREN: HOW TO MINIMIZE THEM?

Objective:

To describe the metabolic and nutritional repercussions of chronic liver disease (CLD), proposing strategies that optimize nutritional therapy in the pre- and post-liver transplantation (LT) period, in order to promote favorable clinical outcomes and adequate growth and development, respectively.

Data sources:

Bibliographic search in the PubMed, Lilacs and SciELO databases of the last 12 years, in English and Portuguese; target population: children from early childhood to adolescence; keywords in Portuguese and their correlates in English: “Liver Transplant,” “Biliary Atresia,” “Nutrition Therapy,” “Nutritional Status,” and “Child”; in addition to Boolean logics “and” and “or,” and the manual search of articles.

Data synthesis:

Malnutrition in children with CLD is a very common condition and an important risk factor for morbidity and mortality. There is an increase in energy and protein demand, as well as difficulties in the absorption of carbohydrates, lipids and micronutrients such as fat-soluble vitamins and some minerals. An increase in the supply of energy, carbohydrates and proteins and micronutrients, especially fat-soluble vitamins, iron, zinc and calcium, is suggested, except in cases of hepatic encephalopathy (this restriction is indicated for a short period).

Conclusions:

Based on metabolic changes and anthropometric and body composition monitoring, a treatment plan should be developed, following the nutritional recommendations available, in order to minimize the negative impact of malnutrition on clinical outcomes during and after LT.

Random forest analysis identifies change in serum creatinine and listing status as the most predictive variables of an outcome for young children on liver transplant waitlist

Young children listed for liver transplant have high waitlist mortality (WL), which is not fully predicted by the PELD score. SRTR database was queried for children < 2 years listed for initial LT during 2002-17 (n = 4973). Subjects were divided into three outcome groups: bad (death or removal for too sick to transplant), good (spontaneous improvement), and transplant. Demographic, clinical, listing history, and laboratory variables at the time of listing (baseline variables), and changes in variables between listing and prior to outcome (trajectory variables) were analyzed using random forest (RF) analysis. 81.5% candidates underwent LT, and 12.3% had bad outcome. RF model including both baseline and trajectory variables improved prediction compared to model using baseline variables alone. RF analyses identified change in serum creatinine and listing status as the most predictive variables. 80% of subjects listed with a PELD score at time of listing and outcome underwent LT, while ~70% of subjects in both bad and good outcome groups were listed with either Status 1 (A or B) prior to an outcome, regardless of initial listing status. Increase in creatinine on LT waitlist was predictive of bad outcome. Longer time spent on WL was predictive of good outcome. Subjects with biliary atresia, liver tumors, and metabolic disease had LT rate >85%, while >20% of subjects with acute liver failure had a bad outcome. Change in creatinine, listing status, need for RRT, time spent on LT waitlist, and diagnoses were the most predictive variables.

Unusual Clinical Course for Untreated Malformative Biliary Atresia Infant: Is Portal Hypertension an Important Driver of Liver Fibrosis?

In biliary atresia, infants left untreated, and in those with unsuccessful porto-enterostomy, hepatic condition and function worsen rapidly towards cirrhosis, malnutrition, portal hypertension with ascites, and variceal haemorrhage; many die within the first 3 years of life unless they benefit from liver replacement. We describe a girl with biliary atresia splenic malformation syndrome, who had portal vein cavernoma and microsplenia; she did not undergo porto-enterostomy. She survived with her native liver over the age of 3 years. Remarkably, she remained in satisfactory condition in absence of ascites or severe hepatic dysfunction, when 4 other similar patients-managed during the same period of time-all had the usual clinical deterioration and ascites, with the need for liver replacement. To our knowledge, there is no similar report in literature. Possible pathogenetic mechanisms and the role of portal hypertension as important factors are discussed.

Higher Waitlist Mortality in Pediatric Acute-on-chronic Liver Failure in the UNOS Database

OBJECTIVES

Acute-on-chronic liver failure (ACLF), whereas increasingly well-defined in adults, has been poorly characterized in pediatric patients other than having a poor prognosis. This study aimed to identify ACLF and evaluate prognosis in the American pediatric population.

METHODS

Modified ACLF definitions (p-CLIF) were applied to 11,300 children listed for liver transplantation from March 2002 through 2017 in the Organ Procurement and Transplantation Network (OPTN) database.

RESULTS

Pediatric ACLF patients have greater mortality within 90 days from listing (46.6% by p-CLIF) than other types of failure (<30%), including acute liver failure, as well as greater mortality within the first 30 and 90 days after transplantation than all other types of liver failure, but do not have increased mortality rates relative to other groups between 90 and 365 days from transplant. Although some ACLF listings also received 1B status, ACLF mortality at 90 days was greater than the general 1B population (50 vs 29.4%). Model for End-Stage Liver Disease/Pediatric End-Stage Liver Disease scores of ACLF patients are lower than 1B listings, and do not predict waitlist or posttransplant death. Greater number of organ failures does correlate with increased mortality. Biliary atresia is the leading etiology of pediatric chronic liver disease, accounting for over 30% of chronic and 45% of ACLF listings, yet is protective against mortality (hazard ratio [HR] = 0.142 for ACLF). Receiving exception approval is independently but similarly protective in ACLF (HR = 0.145).

CONCLUSIONS

These findings pose a challenge for allocation decisions but indicate greater attention to ACLF is needed, as scoring systems may not capture these children's risk of early death, which appears to currently be mitigated by exceptions. Multicenter, clinical, preferably prospective study of ACLF is necessary to determine how to prioritize ACLF relative to other liver failure types to address its relatively higher early mortality.

Admission Characteristics Identify Risk of Pediatric Acute-on-Chronic Liver Failure

OBJECTIVES

Acute-on-chronic liver failure (ACLF) is well-studied in adults and characterized by decompensated cirrhosis, multi-organ failure, and early mortality. Studies of ACLF in children are limited. We sought to characterize the prevalence and clinical factors associated with pediatric ACLF (PACLF).

METHODS

A retrospective review of children 3 months to 18 years listed for liver transplantation and hospitalized for decompensated cirrhosis between January 2007 and December 2017 at a single pediatric hospital. Primary outcome was the development of PACLF, characterized as failure of at least 1 extrahepatic organ (mechanical ventilation, renal replacement therapy, vasoactive medications, grade III/IV hepatic encephalopathy). Characteristics were recorded for each hospitalization.

RESULTS

Sixty-six patients had 186 hospitalizations with mean age at admission 4.0 ± 5.6 years and diagnosis of biliary atresia (BA) in 65%. PACLF developed in 20 patients during 23 hospitalizations (12%) and respiratory failure was most common (17/23, 74%). Duration of intensive care unit stay, 13.1 ± 1.2 days versus 0.6 ± 0.6 days (P < 0.001) and length of stay, 24.3 ± 5.0 days versus 7.9 ± 1.9 days (P = 0.003) were longer in PACLF compared with non-PACLF. Mortality during PACLF hospitalizations was 22%. Clinical factors associated with PACLF were reported from a generalized linear mixed model and included increased admission creatinine (P < 0.0001), increased aspartate aminotransferase (AST) (P = 0.014), increased international normalized ration (INR) (P = 0.0015), and a positive blood culture (P = 0.007).

CONCLUSION

In this pediatric series, PACLF developed in 12% of hospitalizations and mortality was high. Admission creatinine, AST, INR, and presence of a positive blood culture were associated with PACLF development.

Improved Outcomes for Liver Transplantation in Patients with Biliary Atresia Since Pediatric End-Stage Liver Disease Implementation: Analysis of the Society of Pediatric Liver Transplantation Registry

OBJECTIVE

To identify changes in demographics, outcomes, and risk factors for patient and graft loss in patients with biliary atresia undergoing liver transplantation since Pediatric End-Stage Liver Disease implementation (2002).

STUDY DESIGN

Demographics and outcomes were compared between patients enrolled in the Society of Pediatric Liver Transplantation registry before (n = 547) and after (n = 1477) 2002. Kruskal-and χ² Wallis tests identified significant differences between eras. Risk factors for patient and graft loss after 2002 were determined by Cox regression model analysis of time to event data.

RESULTS

Significant patient differences after 2002 support increasing disease severity including more status 1 patients and those with a derived Model for End-Stage Liver Disease/Pediatric End-Stage Liver Disease score of greater than 30 awaiting transplant. Both patient and graft survival improved after 2002 from 90% to 97% and 81% to 90%, respectively (primary transplant; P < .0001). Significant differences in complications within 30 days included reduced relisting for transplant, rejection, culture-positive infection, repeat operation, hepatic artery thrombosis, portal vein thrombosis, and death/transplant before discharge. Multivariable analysis identified deceased technical variant vs whole graft and retransplantation predictive for patient death, hazard ratios of 4.041 and 8.308, respectively. Deceased technical variant vs whole graft (hazard ratio, 1.963) and donor age 0-5 months vs 1-17 years (hazard ratio, 5.525) were risk factors for graft loss.

CONCLUSIONS

The overall outcomes of patients receiving liver transplantation for patients with biliary atresia have improved since 2002 despite evidence of increased disease severity at the time of transplant. Risk factors impacting post-transplant morbidity and mortality in patients with biliary atresia are now mainly surgical including donor variables.

A paradigm shift in the intention-to-transplant children with biliary atresia: Outcomes of 101 cases and a review of the literature

For children with BA who do not benefit from Kasai surgery, the only therapeutic option is liver replacement and transplantation. The very decision to proceed for transplantation is a crucial point in time because it is the first step toward the preparation for the transplantation. The former time point is defined in this analysis as "intent-to-transplant" care pathway. In the life of every BA candidate for liver replacement, this point in time varies and mostly depends on the decision of their primary caring teams-about when to switch from supportive care to transplant, and thus to refer to a transplant center. This intent-to-transplant analysis of a series of 101 consecutive infants that were referred to a single transplant team showed that excellent overall outcome (97% survival) has been achieved overall. However, three deaths occurred that were clearly related to a late referral. This analysis and recent observations from other centers strongly support that the timing for referring these children to a transplant center and/or deciding to list them on the waiting list is currently too late and should be anticipated to what it is currently. This paradigm shift in the intention-to-transplant children is likely necessary for giving a better chance to an increased number of children and impacts positively on the general outcome. Networking and defining new tools for a rapid recognition of the infants who need early transplantation are necessary; centralization of these children may be helpful to achieve better outcomes than currently observed.