Pattern of diagnostic evaluation for the causes of pediatric acute liver failure: an opportunity for quality improvement

Systemic T-cell activation and IFN-γ activity in indeterminate severe hepatitis are reminiscent of hemophagocytic lymphohistiocytosis: Implications for T-cell- and IFN-γ-directed therapies

BACKGROUND

Severe hepatitis cases in children are increasingly recognized, but the exact etiology remains unknown in a significant proportion of patients. Cases of indeterminate severe hepatitis (iSH) may progress to indeterminate pediatric acute liver failure (iPALF), so understanding its immunobiology is critical to preventing disease progression. Hemophagocytic lymphohistiocytosis (HLH) is a systemic hyperinflammatory disorder associated with T-cell and macrophage activation with liver injury.

OBJECTIVES

We hypothesized that a high proportion of patients with iSH demonstrate systemic T-cell activation similar to HLH before developing iPALF and that the degree of T-cell activation in iSH might correlate with outcomes.

METHODS

From 2019 to 2022, 14 patients with iSH and 7 patients with PALF of known, nonimmune etiology were prospectively enrolled. We compared immune signatures of iSH, HLH, known PALF, and healthy controls.

RESULTS

We found that patients with iSH have increased CD8+ T-cell activation and high IFN-γ activity similar to HLH. The amplitude of CD8+ T-cell activation was predictive of iSH progression to iPALF. We also found that in patients with iSH, ferritin had only modest elevation. However, the ratio of age-normalized plasma soluble IL-2 receptor to ferritin level can distinguish iSH from known PALF and HLH. As proof of concept, we report that in 3 patients with steroid-refractory iSH, emapalumab, an IFN-γ blocking antibody used in combination with steroids, improved liver function and may have prevented progression to PALF.

CONCLUSIONS

Flow-based T-cell activation markers could help in early identification and risk stratification for targeted intervention in patients with iSH.

Identification of pediatric activated T-cell hepatitis using clinical immune studies

BACKGROUND AND AIMS

The majority of indeterminate pediatric acute liver failure (PALF) cases are secondary to immune dysregulation, labeled activated T-cell hepatitis (TCHep). We aimed to describe a cohort of children with acute severe hepatitis and PALF and define how clinical immune labs may help identify the TCHep group.

METHODS

Retrospective review of children with acute hepatitis and PALF between March 2020 and August 2022. Patients were classified as known diagnosis, indeterminate hepatitis (IND-Hep), or TCHep (defined by liver biopsy with predominant CD8 T-cell inflammation or development of aplastic anemia).

RESULTS

124 patients were identified: 83 with known diagnoses, 16 with TCHep, and 25 with IND-Hep. Patients with TCHep had significantly increased median total bilirubin levels (7.5 mg/dL (IQR 6.8-8.9) vs 1.5 mg/dL (IQR 1.0-3.6), p < 0.0001), soluble interleukin-2 receptor levels (4512 IU/mL (IQR 4073-5771) vs 2997 IU/mL (IQR 1957-3237), p = 0.02), and percent of CD8+ T-cells expressing perforin (14.5 % (IQR 8.0-20.0) vs 1.0 % (IQR 0.8-1.0), p = 0.004) and granzyme (37.5 % (IQR 15.8-54.8) vs 4.0 % (IQR 2.5-5.5), p = 0.004) compared to IND-Hep patients. Clinical flow cytometry showed that TCHep patients had significantly increased percent CD8+ T cells (29.0 % (IQR 24.5-33.5) vs 23.6 % (IQR 19.8-25.8), p = 0.04) and HLA-DR+ (16.0 % (IQR 14.5-24.5) vs 2.7 (1.8-5.3), p < 0.001) compared to IND-Hep patients indicative of increase in CD8+ T cells that are activated.

CONCLUSIONS

Peripheral blood clinical immune studies demonstrate increased markers of CD8 T-cell activation, proliferation, and cytotoxic function for TCHep patients. These readily available immune function labs can be used to help distinguish patients with TCHep from those with other causes. This provides a non-invasive tool for early detection of potential TCHep before progression to liver failure.

Whole-exome sequencing for genetic diagnosis of idiopathic liver injury in children

Genome-wide approaches, such as whole-exome sequencing (WES), are widely used to decipher the genetic mechanisms underlying inter-individual variability in disease susceptibility. We aimed to dissect inborn monogenic determinants of idiopathic liver injury in otherwise healthy children. We thus performed WES for 20 patients presented with paediatric-onset recurrent elevated transaminases (rELT) or acute liver failure (ALF) of unknown aetiology. A stringent variant screening was undertaken on a manually-curated panel of 380 genes predisposing to inherited human diseases with hepatobiliary involvement in the OMIM database. We identified rare nonsynonymous variants in nine genes in six patients (five rELT and one ALF). We next performed a case-level evaluation to assess the causal concordance between the gene mutated and clinical symptoms of the affected patient. A genetic diagnosis was confirmed in four rELT patients (40%), among whom two carried novel mutations in ACOX2 or PYGL, and two had previously-reported morbid variants in ABCB4 or PHKA2. We also detected rare variants with uncertain clinical significance in CDAN1, JAG1, PCK2, SLC27A5 or VPS33B in rELT or ALF patients. In conclusion, implementation of WES improves diagnostic yield and enables precision management in paediatric cases of liver injury with unknown aetiology, in particular recurrent hypertransaminasemia.

Improved mortality prediction for pediatric acute liver failure using dynamic prediction strategy

OBJECTIVES

To develop and validate a prediction tool for pediatric acute liver failure (PALF) mortality risks that captures the rapid and heterogeneous clinical course for accurate and updated prediction.

METHODS

Data included 1144 participants with PALF enrolled during three phases of the PALF registry study over 15 years. Using joint modeling, we built a dynamic prediction tool for mortality by combining longitudinal trajectories of multiple laboratory and clinical variables. The predictive performance for 7-day and 21-day mortality was assessed using the area under curve (AUC) through cross-validation and split-by-time validation.

RESULTS

We constructed a prognostic joint model that combines the temporal trajectories of international normalized ratio, total bilirubin, hepatic encephalopathy, platelet count, and serum creatinine. Dynamic prediction using updated information improved predictive performance over static prediction using the information at enrollment (Day 0) only. In cross-validation, AUC increased from 0.784 to 0.887 when measurements obtained between Days 1 and 2 were incorporated. AUC remained similar when we used the earlier subset of the sample for training and the later subset for testing.

CONCLUSIONS

Serial measurements of five variables in the first few days of PALF capture the dynamic clinical course of the disease and improve risk prediction for mortality. Continuous disease monitoring and updating risk prognosis are beneficial for timely and judicious medical decisions.

Disorders of vesicular trafficking presenting with recurrent acute liver failure: NBAS, RINT1, and SCYL1 deficiency

Among genetic disorders of vesicular trafficking, there are three causing recurrent acute liver failure (RALF): NBAS, RINT1, and SCYL1-associated disease. These three disorders are characterized by liver crises triggered by febrile infections and account for a relevant proportion of RALF causes. While the frequency and severity of liver crises in NBAS and RINT1-associated disease decrease with age, patients with SCYL1 variants present with a progressive, cholestatic course. In all three diseases, there is a multisystemic, partially overlapping phenotype with variable expression, including liver, skeletal, and nervous systems, all organ systems with high secretory activity. There are no specific biomarkers for these diseases, and whole exome sequencing should be performed in patients with RALF of unknown etiology. NBAS, SCYL1, and RINT1 are involved in antegrade and retrograde vesicular trafficking. Pathomechanisms remain unclarified, but there is evidence of a decrease in concentration and stability of the protein primarily affected by the respective gene defect and its interaction partners, potentially causing impairment of vesicular transport. The impairment of protein secretion by compromised antegrade transport provides a possible explanation for different organ manifestations such as bone alteration due to lack of collagens or diabetes mellitus when insulin secretion is affected. Dysfunction of retrograde transport impairs membrane recycling and autophagy. The impairment of vesicular trafficking results in increased endoplasmic reticulum stress, which, in hepatocytes, can progress to hepatocytolysis. While there is no curative therapy, an early and consequent implementation of an emergency protocol seems crucial for optimal therapeutic management.

Therapeutic Plasma Exchange in Children With Acute and Acuteon-Chronic Liver Failure: A Single-Center Experience

OBJECTIVES

Acute liver failure is a life-threatening condition that may result in death if liver transplant is not performed. The aim of our study was to evaluate patients with acute liver failure or acute-on-chronic liver failure who were followed and treated with therapeutic plasma exchange in a pediatric intensive care unit until they achieved clinical recovery or underwent liver transplant.

MATERIALS AND METHODS

In this retrospective, singlecenter study, we included patients with acute liver failure or acute-on-chronic liver failure who received therapeutic plasma exchange between April 2020 and December 2021. Clinical findings, laboratory findings, extracorporeal therapies, Pediatric Risk of Mortality III and liver injury unit scores and pretherapy and posttherapy hepatic encephalopathy scores, Model for End-Stage Liver Disease score, and Pediatric End-Stage Liver Disease score were retrospectively analyzed.

RESULTS

Nineteen patients were included in the study. One patient was excluded because of positivity for COVID-19. The mean age of children was 62.06 months, ranging from 5 months to 16 years (12 boys, 6 girls). Thirteen patients (72.2%) had acute liver failure, and 5 patients (27.8%) had acute-on-chronic liver failure. No significant difference was shown for mean liver injury unit score (P = .673) and Pediatric Logistic Organ Dysfunction score (P = .168) between patients who died and patients who received treatment at the inpatient clinic and transplant center. However, Pediatric Risk of Mortality score and the mean Model for End-Stage Liver Disease/Pediatric End-Stage Liver Disease scores before therapeutic plasma exchange and after therapeutic plasma exchange (after 3 consecutive days of treatment) were statistically significant (P = .001 and P = .004).

CONCLUSIONS

Therapeutic plasma exchange may assist bridge to liver transplant or assist with spontaneous recovery of liver failure in pediatric patients with acute liver failure or acute-on-chronic liver failure.

Hepatitis A-induced acute liver failure with glucose 6 phosphate dehydrogenase deficiency induced hemolysis and renal failure

Hepatitis A is the most prevalent viral hepatitis in India and rarely can lead to life-threatening complications such as acute liver failure (ALF). Glucose 6 phosphate dehydrogenase (G6PD) deficiency is the most common enzyme deficiency in the world, and in the setting of acute viral hepatitis, it can cause massive intravascular hemolysis, resulting in acute kidney injury. Here, we report a case of a 12-year-old male child who had hepatitis A-associated ALF, which was complicated by massive hemolysis due to underlying G6PD deficiency, manifesting as acute renal failure requiring renal replacement therapy with other supportive management. He had a prolonged, protracted stormy clinical course, which was further complicated by dialysis disequilibrium syndrome, posterior reversible encephalopathy syndrome, and nosocomial sepsis, which improved over 4 weeks. Our case highlights the importance of having high index of clinical suspicion for G6PD deficiency in a child with acute viral hepatitis with complications.

Clinical Aspects and Etiologic Investigation of Pediatric Patients With Acute Liver Failure

A new outbreak of hepatitis of unknown origin raised awareness in the international community. A few reports have attempted to associate new cases with adenovirus infection and the immunologic effects of previous SARS-CoV-2 infections through a superantigen mechanism. Moreover, according to a case series, viral isolates were identified in 7 of 10 cases of pediatric patients with hepatitis of unknown origin and acute liver failure. Adenovirus was detected by respiratory secretion polymerase chain reaction in 2 patients, with neither presenting with SARS-CoV-2 acute infection. Clinical and laboratory descriptions and cross-referencing epidemiologic and pathophysiological data can help identify possible disease etiologies.

Etiology of viral induced acute liver failure and defensins as potential therapeutic agents in ALF treatment

Acute liver failure (ALF) is a rare and severe disease, which, despite continuous advances in medicine, is still characterized by high mortality (65-85%). Very often, a liver transplant is the only effective treatment for ALF. Despite the implementation of prophylactic vaccinations in the world, the viral background of ALF is still a problem and leads to many deaths. Depending on the cause of ALF, it is sometimes possible to reverse this condition with appropriate therapies, which is why the search for effective antiviral agents seems to be a very desirable direction of research. Defensins, which are our natural antimicrobial peptides, have a very high potential to be used as therapeutic agents for infectious liver diseases. Previous studies on the expression of human defensins have shown that increased expression of human α and β-defensins in HCV and HBV infections is associated with a better response to treatment. Unfortunately, conducting clinical trials for ALF is very difficult due to the severity of the disease and the low incidence, therefore animal models are important for the development of new therapeutic strategies. One of the best animal models that has real reference to research on acute liver failure (ALF) is rabbit hemorrhagic disease in rabbits caused by the Lagovirus europaeus virus. So far, there have been no studies on the potential of defensins in rabbits infected with Lagovirus europaeus virus.

Identifying the Aetiology of Acute Liver Failure Is Crucial to Impact Positively on Outcome

Management of children with acute liver failure is challenging. In this retrospective study, paediatric patients diagnosed with ALF at our centre, in the last 26 years, were divided into two groups (G1 = diagnosed from 1997 to 2009; G2 = from 2010 to 2022) and compared to see whether they differed with regard to aetiologies, need for liver transplantation (LT), and outcome. A total of 90 children (median age 4.6 years, range 1.2-10.4; M/F = 43/47) were diagnosed with ALF, by autoimmune hepatitis (AIH) in 16 (18%), paracetamol overdose in 10 (11%), Wilson disease in 8 (9%), and other causes in 19 (21%); 37 (41%) had indeterminate ALF (ID-ALF). Comparing the two periods, the clinical features, aetiologies, and median peak values of INR [3.8 (2.9-4.8) in G1 vs. 3.2 (2.4-4.8) in G2] were similar (p > 0.05). The percentage of ID-ALF tended to be higher in G1 compared to G2 (50% vs. 32% in G2, p = 0.09). The overall percentage of patients diagnosed with Wilson disease, inborn errors of metabolism, neonatal hemochromatosis or viral infection was higher in G2 (34% vs. 13% in G1, p = 0.02). A total of 21/90 patients (23%; 5 with indeterminate ALF) were treated with steroids; 12 (14%) required extracorporeal liver support treatment. The need for LT was significantly higher in G1 compared to G2 (56% vs. 34%; p = 0.032). Among 37 children with ID-ALF, 6 (16%) developed aplastic anaemia (all in G2, p < 0.001). The survival rate at last follow up was of 94%. On a KM curve, the transplant-free survival was lower in G1 compared to G2. In conclusion, we report a lower need for LT in children diagnosed with PALF during the most recent period compared to the first era. This suggests improvements over time in the diagnosis and management of children with PALF.

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 Survival Outcomes beyond the First Year after Liver Transplantation in Pediatric Acute Liver Failure Compared with Biliary Atresia: A Large-Volume Living Donor Liver Transplantation Single-Center Study

Pediatric acute liver failure (PALF) is a common cause of liver transplantation (LT) but showed poor post-LT outcomes. We reviewed 36 PALF patients and 120 BA patients who underwent LT in our institution. The cause of PALF was unknown in 66.7%. PALF patients were older (6.2 vs. 2.9 years) with higher PELD scores (31.5 vs. 24.4) and shorter waitlist time (15.7 vs. 256.1 days) (p < 0.01). PALF patients showed higher rates of post-transplant renal replacement therapy (RRT) (13.9% vs. 4.2%) and hepatic artery complications (13.9% vs. 0.8%), while portal vein complications rates were lower (0% vs. 10.8%), (p < 0.05). Although PALF patients showed lower 5-year survival rates (77.8% vs. 95.0 %, p < 0.01), the 5-year survival rates of patients who lived beyond the first year were comparable (96.6% vs. 98.3%, p = 0.516). The most common cause of deaths within one year was graft failure (75.0%) in PALF patients, but infection (67.7%) in BA patients. In multivariate analysis, lower body weight, hepatic artery complications and post-transplant RRT were associated with worse survival outcomes (p < 0.05). In conclusion, physicians should be alert to monitor the immediate postoperative graft dysfunction and hepatic artery complications and patients on post-transplant RRT in order to improve survival outcomes in PALF patients.

Acute hepatitis of unknown origin in children: A combination of factors

On 5 April 2022, the World Health Organization was notified of 10 cases of severe acute hepatitis of unknown etiology in children under 10 years of age in the United Kingdom. Although the exact cause of a proportion of pediatric acute hepatitis and acute liver failure cases was unclear, the above event has caused widespread concern worldwide. As of 14 September 2022, approximately 1,296 probable cases of acute hepatitis of unknown etiology have been reported from 37 countries/regions, of which approximately 55 required or received liver transplantation and 29 died. Although the etiology of acute hepatitis of unknown origin in children remains unclear, many hypotheses have been proposed about the disease. Instead of individual factors such as "adenovirus infection," "SARS-CoV-2 related," and "Adeno-associated virus 2 with helper virus coinfection," it is more likely due to a combination of factors. Accordingly, there is an urgent need for more data and research to clarify the disease etiology. This review aims to provide a historical perspective of acute hepatitis of unknown etiology in children in the past decades and summarize the current hypothesis and evidence on this emerging disease.

An Update on Pediatric Acute Liver Failure: Emerging Understanding of the Impact of Immune Dysregulation and Novel Opportunities for Intervention

Pediatric acute liver failure (PALF) is a complex, unpredictable, often rapidly progressive, potentially devastating clinical syndrome that occurs in infants, children, and adolescents without pre-existing liver disease. PALF is characterized by acute onset of hepatocellular injury and liver-based coagulopathy, frequently accompanied by hepatic encephalopathy. Etiologies include drug and toxin exposures, metabolic and genetic disorders, infections, and immune-mediated disease. PALF management primarily involves early contact with and consideration of transfer to a pediatric liver transplant center and intensive supportive multidisciplinary clinical care, with targeted therapies available for a subset of causes. Outcomes include survival with native liver, death, and liver transplantation. Efforts to develop reliable clinical prognostic tools to predict PALF outcomes early in the course of disease have not yet been fulfilled, and the possibility remains that some transplanted PALF patients might have survived without transplantation.

Indeterminate pediatric acute liver failure: Clinical characteristics of a temporal cluster of five children in the Netherlands in the spring of 2022

There is increasing global concern of severe acute hepatitis of unknown etiology in young children. In early 2022, our center for liver transplantation in the Netherlands treated five children who presented in short succession with indeterminate acute liver failure. Four children underwent liver transplantation, one spontaneously recovered. Here we delineate the clinical course and comprehensive diagnostic workup of these patients. Three of five patients showed a gradual decline of liver synthetic function and had mild neurological symptoms. Their clinical and histological findings were consistent with hepatitis. These three patients all had a past SARS-CoV-2 infection and two of them were positive for adenovirus DNA. The other two patients presented with advanced liver failure and encephalopathy and underwent dialysis as a bridge to transplantation. One of these children spontaneously recovered. We discuss this cluster of patients in the context of the currently elevated incidence of severe acute hepatitis in children.

Outcomes Analyses of Pediatric Acute Liver Failure Subjects Listed for Liver Transplantation

BACKGROUND

We characterized recent outcomes in US pediatric acute liver failure (PALF) subjects listed for liver transplantation (LT) using the Scientific Registry of Transplant Recipients (SRTR) database.

METHODS

Pediatric subjects listed for LT from 2002 to 2015 were assigned to the "PALF" group based on status 1/1A listing, INR >2, no hepatic artery thrombosis, and no primary graft nonfunction (N = 397). Subjects were assigned to the "non-PALF" group if listed with any status other than 1/1A (N = 4509).

RESULTS

The PALF group had more infants <3 months of age and males at listing for LT compared to the non-PALF group. Two-thirds of PALF subjects had an indeterminate etiology. LT waitlist survival was significantly worse in the PALF group compared to the non-PALF group. Likelihood of removal from the LT waitlist for being "too sick" was higher, while that of removal for "spontaneous recovery" was lower in PALF subjects. Post-LT short-term (30 days) and long-term (60 months) outcomes were also significantly worse in PALF versus non-PALF subjects. PALF subjects who underwent living-donor-liver-transplant (LDLT) had similar LT waitlist times and post-LT survival compared to those undergoing deceased-donor-liver-transplant (DDLT). Over the study period, we observed a decreased number of liver transplants, and increase in LT waitlist- and short-term post-LT-survival in PALF subjects.

CONCLUSION

LT waitlist and post-LT outcomes are worse in PALF subjects compared to non-PALF subjects. PALF subjects who undergo LDLT have similar waitlist times and post-LT outcomes compared to those undergoing DDLT.

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.

Case Report: A Case of Epstein-Barr Virus-Associated Acute Liver Failure Requiring Hematopoietic Cell Transplantation After Emergent Liver Transplantation

Hepatic manifestations of Epstein-Barr virus (EBV) infection are relatively common, mild, and self-limiting. Although fulminant hepatic failure has been reported in a few cases, the contributing factors are unclear. This report discusses a pediatric case of EBV-associated acute liver failure that required urgent liver transplantation; however, liver damage continued to progress post-liver replacement. Monoclonal CD8+ T cells that preferentially infiltrated the native and transplanted liver were positive for EBV-encoded small RNA, suggesting a pathophysiology similar to that of EBV-associated hemophagocytic lymphohistiocytosis and chronic active EBV infection. Therefore, subsequent chemotherapy and hematopoietic cell transplantation was conducted, which led to cure. This is the first case of EBV-associated acute liver failure that relapsed post-liver transplant. As such, it sheds light on an under-recognized clinical entity: liver-restricted hyperinflammation caused by EBV-infected monoclonal CD8+ T cells. This phenomenon needs to be recognized and differentiated from hepatitis/hepatic failure caused by EBV-infected B cells, which has a relatively benign clinical course.

Case report: A case of severe acute hepatitis of unknown origin

According to analyses of etiology, clinical features, diagnostic methods, and treatment strategies by summarizing a case of unexplained acute hepatitis recently experienced, we are aiming to provide some information to enrich the clinical experience in diagnosis and treatment of severe acute hepatitis of unknown etiology in young children. A boy, aged 10 years and 6 months old, was admitted to the hospital due to acute abdominal pain, jaundice, and exceptionally high levels of ALT and AST. A range of measures, including patient history, physical examination, and routine laboratory testing, were performed. Furthermore, strategies such as trio-based next-generation sequencing (Trio-NGS) and liver biopsy, as well as metagenomic NGS (mNGS) of blood and liver samples were also performed. In summary, this case was an acute severe non-A-E hepatitis that is a probable case with hepatitis of unknown origin. Immunohistochemical analysis showed an immune injury in liver tissues. Torque teno virus (TTV) sequences were detected by mNGS assay. As for treatment strategies, in addition to general treatment, this patient also underwent plasmapheresis and methylprednisolone treatment due to disease deterioration. The patient's liver function was improved afterward and discharged after one month of treatment. Taken together, this work reported the clinical feature and treatment of severe acute hepatitis with non-A-E hepatitis in detail. The potential mechanism of liver damage might be due to an immune attack in which TTV might play a role as a co-factor.

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.

Transcriptional Analysis of Liver Tissue Identifies Distinct Phenotypes of Indeterminate Pediatric Acute Liver Failure

Many patients with indeterminate pediatric acute liver failure (PALF) have evidence of T-cell driven immune injury; however, the precise inflammatory pathways are not well defined. We have characterized the hepatic cytokine and transcriptional signatures of patients with PALF. A retrospective review was performed on 22 children presenting with indeterminate (IND-PALF; n = 17) or other known diagnoses (DX-PALF; n = 6) with available archived liver tissue. Specimens were stained for clusters of differentiation 8 (CD8) T cells and scored as dense, moderate, or minimal. Measurement of immune analytes and RNA sequencing (RNA-seq) was performed on whole-liver tissue. Immune analyte data were analyzed by principal component analysis, and RNA-seq was analyzed by unsupervised hierarchical clustering, differential gene expression, and gene-set enrichment analysis. Most patients with IND-PALF (94%) had dense/moderate CD8 staining and were characterized by Th1 immune analytes including tumor necrosis factor α, interferon γ (IFN-γ), interleukin (IL) 1β, IL-12, C-X-C motif chemokine ligand (CXCL) 9, and CXCL12. Transcriptional analyses identified two transcriptional PALF phenotypes. Most patients in group 1 (91%) had IND-PALF and dense/moderate CD8 staining. This group was characterized by increased expression of genes and cell subset-specific signatures related to innate inflammation, T-cell activation, and antigen stimulation. Group 1 expressed significantly higher levels of gene signatures for regulatory T cells, macrophages, Th1 cells, T effector memory cells, cytotoxic T cells, and activated dendritic cells (adjusted P < 0.05). In contrast, patients in group 2 exhibited increased expression for genes involved in metabolic processes. Conclusion: Patients with IND-PALF have evidence of a Th1-mediated inflammatory response driven by IFN-γ. Transcriptional analyses suggest that a complex immune network may regulate an immune-driven PALF phenotype with less evidence of metabolic processes. These findings provide insight into mechanisms of hepatic injury in PALF, areas for future research, and potential therapeutic targets.

Safety of High-Volume Plasmapheresis in Children With Acute Liver Failure

OBJECTIVES

Paediatric acute liver failure (P-ALF) is a rare condition and is associated with a high mortality rate. Management of P-ALF aims to stabilise vital organ functions and to remove circulating toxins and provide vital plasma factors that are lacking. High-volume plasmapheresis (HVP) removes protein-bound substances and improves survival in adult ALF. It is unknown if this effect can be extrapolated to P-ALF. The aim of this study is to report the safety and feasibility of HVP in P-ALF.

METHODS

Children with P-ALF were offered HVP if bilirubin was higher than 200 μmol/L or if the aetiology was toxic hepatitis. HVP was performed with fresh frozen plasma corresponding to 10% of the body weight on a minimum of 3 consecutive days. Diagnostics, biochemical and clinical data during HVP as well as outcome data after 3 months were collected from 2012 to 2019 and retrospectively analysed.

RESULTS

Sixteen children were treated by HVP and completed at least one series of three treatment sessions with HVP. The only complication seen was an increase in pH > 7.55 in three children within the first 12 hours and was corrected with hydrochloric acid. No bleeding or septic episodes were noted during HVP. Eight children survived without liver transplantation, two survived after successful grafting and a total of six children died. The liver injury unit score between survivors with their own liver and the rest, the two groups was significantly different (P = 0.005).

CONCLUSION

HVP with fresh frozen plasma is feasible and well tolerated in children with P-ALF. No serious adverse events and no procedure-related mortality were observed.

Inborn Errors of Metabolism in a Tertiary Pediatric Intensive Care Unit

Few studies exist describing resources and care of pediatric patients with inborn errors of metabolism (IEM) admitted to pediatric intensive care unit (PICU). This study aims to characterize the PICU admissions of these patients to provide better diagnostic and therapeutic care in the future. Retrospective analysis of pediatric patients with IEM admitted to the PICU of a tertiary care center at a metabolic referral university hospital from 2009 to 2019 was included. Clinical information and demographic data were collected from PICU clinical records. During this period, 2% (n = 88 admissions, from 65 children) out of 4,459 PICU admissions had clinical features of IEM. The median age was 3 years (range: 3 days–21 years) and 33 were male. Median age at diagnosis was 3 months; 23/65 patients with intoxication disorders, 21/65 with disorders of energy metabolism, 17/65 with disorders of complex molecules, and 4/65 with other metabolic diseases (congenital lipodystrophy, Menkes' disease, hyperammonemia without a diagnosis). From a total of 88 admissions, 62 were due to metabolic decompensation (infection—38, neonatal period decompensation—14, external accident—5, prolonged fasting—2, and therapeutic noncompliance—3) and 26 elective admissions after a scheduled surgery/elective procedure. The most frequent clinical presentations were respiratory failure (30/88) and neurological deterioration (26/88). Mechanical ventilation was required in 30 patients and parenteral nutrition in 6 patients. Extracorporeal removal therapy was required in 16 pediatric patients (12 with maple syrup urine disease and 4 with hyperammonemia) with a median duration of 19 hours. The median length of PICU stay was 3.6 days (3 hours–35 days). Eight patients died during the studied period (cerebral edema—2, massive hemorrhage—5, and malignant arrhythmia—1). Acute decompensation was the main cause of admission in PICU in these patients. The complexity of these diseases requires specialized human and technical resources, with an important impact on the recovery and survival of these patients.

Pediatric chronic liver failure-sequential organ failure assessment score and outcome of acute liver failure in children

Aim of the study

Liver transplantation remains the only definitive treatment for children with acute liver failure proven to have irreversible liver injury. Many prognostic models have been used for outcome prediction in pediatric acute liver failure to select patients in a real need of liver transplantation, but unfortunately all have shown inconsistent reproducibility and prognostic accuracy. The aim of this study was to evaluate the pediatric chronic liver failure sequential organ failure assessment (pCLIF-SOFA) score as a predictor of pediatric acute liver failure outcome.

Material and methods

Clinical and laboratory data of 41 children with acute liver failure admitted to the National Liver Institute – Menoufia University were collected retrospectively and used for calculation of both pCLIF-SOFA and Pediatric End-Stage Liver Disease (PELD)/Model for End-Stage Liver Disease (MELD) scores on the day of admission, then statistical analysis was performed to identify the ability of these scores to predict the outcome.

Results

According to the outcome, children enrolled in this study were allocated to survived (n = 16) and died (n = 25) groups, which were age and sex matched. The non-survival group had significantly higher values of both pCLIF-SOFA score (11 [7-13]) and PELD/MELD score (36 [18-42]) than those of the survival group (8 [7-11], 27.5 [15-45]; p < 0.001, p = 0.004) respectively. Both pCLIF-SOFA and PELD/MELD scores at cut-off values > 8 and > 30 respectively on admission could predict death in children with acute liver failure (ALF) with high sensitivity, but with higher specificity, positive and negative predictive values for pCLIF-SOFA.

Conclusions

pCLIF-SOFA is a good predictor of death in pediatric acute liver failure.

Infantile fever-triggered acute liver failure caused by novel neuroblastoma amplified sequence mutations: a case report

BACKGROUND

Infantile liver failure syndrome-2 (ILFS2) is caused by neuroblastoma amplified sequence (NBAS) mutation. The disease is characterized by recurrent episodes of acute liver failure (ALF) or by liver crisis triggered by recurrent episodes of fever and complete recovery.

CASE PRESENTATION

Here, we describe the case of a Chinese girl with typical clinical manifestation of ILFS2 without exhibition of extrahepatic involvement. The patient harbored novel compound heterozygous mutations in the NBAS region (c.3386C > T (p.Ser1129Phe), c.1A > C (p.Met1Leu) and c.875G > A (p.Gly292Glu)), mutations which have not been previously reported. After administration of antipyretics and intravenous glucose and electrolyte administration, the patient recovered fully.

CONCLUSION

Through the present study, we recommend that ILFS2 should be taken into consideration during the differential diagnosis of children with recurrent, fever-triggered ALF. While the definitive diagnosis of ILFS2 remains dependent on genetic sequencing and discovery of NBAS, early antipyretic treatment is recommended to prevent liver crisis.

Acute liver failure associated with metabolic diseases: A 10-year single-center experience

BACKGROUND

Acute liver failure (ALF) is a rare multisystemic disease occurring in individuals with no history of liver disease, characterized by coagulopathy and / or hepatic encephalopathy secondary to acute liver injury. It is mostly caused by viral infections, drug intoxication, and metabolic diseases (MD), and can also have an indeterminate etiology. In this study, we aimed to evaluate the demographic and clinical characteristics and clinical outcomes of the patients that presented to our clinic with MD-associated ALF.

METHODS

This retrospective study reviewed age, gender, parental consanguinity, family history, presence of encephalopathy, laboratory parameters, and clinical outcomes of the patients that presented to our clinic between January 2009 and January 2019. Patients with MD-associated ALF were compared with patients in whom ALF was associated with other etiologies.

RESULTS

The study included 39 patients (53.8% boys; mean age + SD 6.13 ± 1.43 years). The total and direct bilirubin, international normalized ratio, and ammoniac levels were significantly higher in patients with MD than in the others (P < 0.05). Moreover, the incidences of hypoglycemia, death of a sibling and / or a family history of liver disease were also higher in patients with MD than in the others (P < 0.05). On the other hand, alanine aminotransferase (ALT) levels were significantly higher in patients with other etiologies.

CONCLUSIONS

Metabolic diseases should be kept in mind in patients with a history of parental consanguinity and a positive family history of liver disease along with less increased alanine aminotransferase than expected, and increased bilirubin, international normalized ratio, and ammoniac levels and hypoglycemia. As the number of these parameters increases, the chance of diagnosis increases.

Transplant-free Survival in Chronic Liver Disease Presenting as Acute Liver Failure in Childhood

BACKGROUND

In adults, the absence of a preexisting chronic liver disease (CLD) is required to diagnose acute liver failure (ALF). The pediatric classification does not consider this aspect, thus previous studies pooled together children with ALF and children with unknown CLD presenting with acute hepatic decompensation (ALF-CLD). We aimed to compare prevalence, features, and outcome of children with ALF-CLD to those with a proper ALF.

METHODS

Patients admitted between 1996 and 2017 because of ALF defined by Pediatric Acute Liver Failure criteria (raised transaminases, International Normal Ratio ≥2.0, no history of liver disease) were classified as ALF-CLD if diagnosed with autoimmune hepatitis, Wilson disease, Budd-Chiari syndrome, hepatitis B virus reactivation, inborn errors of metabolism. The others were classified as ALF.

RESULTS

Seventy-four children (median age, 4 years; 1.0-8.8; male/female, 36/38] with ALF were found; 18 of <1 year of age were excluded. Fifty-six (median age, 6.6 years; 2.7-11.7; male/female, 23/33], 22 with ALF-CLD (autoimmune hepatitis, n = 14; Wilson disease, n = 6; inborn errors of metabolism, n = 2) and 34 with ALF (paracetamol overdose, n = 6; viral infections, n = 3; mushroom poisoning, n = 5; indeterminate, n = 20) were compared. In ALF-CLD, the median age at onset was higher, alanine aminotransferase, albumin, and International Normal Ratio levels were lower, splenomegaly, ascites, and cirrhosis were more common (all P < 0.01). On multivariate analysis, the diagnosis of ALF-CLD was an independent predictor of transplant-free survival (P = 0.006).

CONCLUSIONS

In children, ALF-CLD is common, has peculiar features, and is associated with a favorable outcome. This study suggests the need to distinguish this entity from other forms of ALF in children.

RINT1 Bi-allelic Variations Cause Infantile-Onset Recurrent Acute Liver Failure and Skeletal Abnormalities

Pediatric acute liver failure (ALF) is life threatening with genetic, immunologic, and environmental etiologies. Approximately half of all cases remain unexplained. Recurrent ALF (RALF) in infants describes repeated episodes of severe liver injury with recovery of hepatic function between crises. We describe bi-allelic RINT1 alterations as the cause of a multisystem disorder including RALF and skeletal abnormalities. Three unrelated individuals with RALF onset ≤3 years of age have splice alterations at the same position (c.1333+1G>A or G>T) in trans with a missense (p.Ala368Thr or p.Leu370Pro) or in-frame deletion (p.Val618_Lys619del) in RINT1. ALF episodes are concomitant with fever/infection and not all individuals have complete normalization of liver function testing between episodes. Liver biopsies revealed nonspecific liver damage including fibrosis, steatosis, or mild increases in Kupffer cells. Skeletal imaging revealed abnormalities affecting the vertebrae and pelvis. Dermal fibroblasts showed splice-variant mediated skipping of exon 9 leading to an out-of-frame product and nonsense-mediated transcript decay. Fibroblasts also revealed decreased RINT1 protein, abnormal Golgi morphology, and impaired autophagic flux compared to control. RINT1 interacts with NBAS, recently implicated in RALF, and UVRAG, to facilitate Golgi-to-ER retrograde vesicle transport. During nutrient depletion or infection, Golgi-to-ER transport is suppressed and autophagy is promoted through UVRAG regulation by mTOR. Aberrant autophagy has been associated with the development of similar skeletal abnormalities and also with liver disease, suggesting that disruption of these RINT1 functions may explain the liver and skeletal findings. Clarifying the pathomechanism underlying this gene-disease relationship may inform therapeutic opportunities.

Clinical and biochemical footprints of inherited metabolic diseases. II. Metabolic liver diseases

Inherited metabolic diseases account for about one third of pediatric patients with hepatomegaly, acute liver failure, cirrhosis or cholestasis. Specifically for pediatric acute liver failure, they account for 10-15% of cases, with a mortality of 22-65%. The percentage of acute liver failure caused by an inherited metabolic disease in children <2-3 years of age is even higher, ranging from a third to half of all cases. Metabolic liver disease accounts for 8-13% of all pediatric liver transplantations. Despite this high burden of disease, underdiagnosis remains common. We reviewed and updated the list of known metabolic etiologies associated with various types of metabolic liver involvement, and found 142 relevant inborn errors of metabolism. This represents the second of a series of articles attempting to create and maintain a comprehensive list of clinical and metabolic differential diagnoses according to system involvement.

Corticosteroid Therapy for Indeterminate Pediatric Acute Liver Failure and Aplastic Anemia with Acute Hepatitis

OBJECTIVE

To examine the characteristics and outcomes of a multicenter patient cohort with indeterminate pediatric acute liver failure (IND-PALF) and with aplastic anemia with acute hepatitis treated with corticosteroids.

STUDY DESIGN

Retrospective study of patients age 1-17 years with IND-PALF and aplastic anemia with acute hepatitis who presented between 2009 and 2018 to 1 of 4 institutions and were treated with corticosteroids for presumed immune dysregulation.

RESULTS

Of 28 patients with IND-PALF (median of 4.0 years of age [range 1-16] and 71% male) 71% (n = 20) were treated with 0.5-4 mg/kg/day of intravenous methylprednisolone, and 8 patients received 10 mg/kg/day followed by a taper. By 21 days postcorticosteroid initiation, 14 patients (50%) underwent liver transplantation, 13 patients (46%) recovered with their native liver, and 1 patient (4%) died. Patients who recovered with their native liver received a median of 139 days (range 19-749) of corticosteroid therapy, with a median of 12 days (range 1-240) to international normalized ratio ≤1.2. Patients with aplastic anemia with acute hepatitis (n = 6; median of 9.5 years of age [range 1-12], 83% male), received 1-2 mg/kg/day of methylprednisolone for a median of 100 days (range 63-183), and all recovered with their native liver. One patient with IND-PALF and 2 patients with aplastic anemia with acute hepatitis developed a serious infection within 90 days postcorticosteroid initiation.

CONCLUSIONS

Many patients with IND-PALF or aplastic anemia with acute hepatitis that were treated with corticosteroids improved, but survival with native liver may not be different from historical reports. A randomized controlled trial exploring the benefits and risks of steroid therapy is needed before it is adopted broadly.

Novel neuroblastoma amplified sequence (NBAS) mutations in a Japanese boy with fever-triggered recurrent acute liver failure

Biallelic mutations in the neuroblastoma amplified sequence (NBAS) gene have been reported to cause two different clinical spectra: short stature with optic nerve atrophy and Pelger-Huët anomaly (SOPH) syndrome and infantile liver failure syndrome 2 (ILFS2). Here, we describe a case of a 3-year-old Japanese boy who presented with fever-triggered recurrent acute liver failure (ALF). The clinical characteristics were considerable elevation of liver enzymes, severe coagulopathy, and acute renal failure. In addition to the liver phenotype, he had short stature and Pelger-Huët anomaly in the peripheral granulocytes. Whole-exome and Sanger sequencing of the patient and his parents revealed that he carried novel compound heterozygous missense mutations in NBAS, c.1018G>C (p.Gly340Arg) and c.2674 G>T (p.Val892Phe). Both mutations affect evolutionarily conserved amino acid residues and are predicted to be highly damaging. Immunoblot analysis of the patient’s skin fibroblasts showed a normal NBAS protein level but a reduced protein level of its interaction partner, p31, involved in Golgi-to-endoplasmic reticulum retrograde vesicular trafficking. We recommend NBAS gene analysis in children with unexplained fever-triggered recurrent ALF or liver dysfunction. Early antipyretic therapy may prevent further episodes of ALF.

Novel mutations in a gene called NBAS have been identified in a Japanese boy with recurrent acute liver failure. Researchers led by Junko Matsuda from Kawasaki Medical School, Okayama, Japan, searched for the genetic cause of a young boy’s recurrent episodes of fever-triggered liver dysfunction. They sequenced the entire protein-coding portion of his genome and that of his parents. They found that the boy had inherited two defective copies of the NBAS (neuroblastoma amplified sequence) gene, one from each parent. Laboratory experiments indicated that these mutations impaired the ability of the protein encoded by NBAS to function correctly. The authors recommend testing for NBAS mutations in any children with unexplained liver problems, and then treating with fever-reducing therapies to prevent future life-threatening episodes of liver failure.

Mutation in the Neuroblastoma Amplified Sequence Gene as a Cause of Recurrent Acute Liver Failure, Acute Kidney Injury, and Status Epilepticus

Cause of acute liver failure (ALF) in children remains elusive in almost 50% cases. It is caused by viral hepatitis, hemophagocytic lymphohistiocytosis, autoimmune diseases, drugs, and metabolic diseases. Recurrent ALF with intermittent recovery is caused by metabolic disorders such as fatty acid oxidation defects, respiratory chain disorders, or unknown repeat insult from diet, toxins, or viruses. Biallelic mutations in the neuroblastoma amplified sequence (NBAS) gene have recently been associated with infantile liver failure syndrome type 2. It is associated with ALF during intercurrent febrile illness and complete recovery with conservative management. A 12-year-old boy presented with history of recurrent ALF since infancy with complete recovery and no etiological clue. He was detected to have homozygous pathogenic variation in NBAS gene which has been recently described in the literature to be associated with recurrent ALF. This is the first such case report from India. During the episode of ALF, when he presented to us, he had acute kidney injury and status epilepticus. The association of other organs with NBAS protein deficiency-associated ALF needs to be established.

Acute Liver Failure in Children

“Acute liver failure” (ALF) and “fulminant liver failure” are terms used interchangeably to describe severe and sudden onset of liver cell dysfunction leading on to synthetic and detoxification failure across all age groups. Considerable variations exist between ALF in children and adults, in terms of aetiology and prognosis. Encephalopathy is not essential to make a diagnosis of ALF in children but when present has a bad prognosis. Early recognition of ALF and initiation of supportive management improve the outcome. Liver transplantation remains the only definitive treatment when supportive medical management fails.

SOPH Syndrome with Growth Hormone Deficiency, Normal Bone Age, and Novel Compound Heterozygous Mutations in NBAS

BACKGROUND

Short stature with optic atrophy and Pelger-Huet anomaly (SOPH; MIM 614800) syndrome is a genetic disease caused by mutation in the neuroblastoma amplified sequence (NBAS) gene.

CASE REPORT

We present a 11-year-old Chinese boy with SOPH syndrome, growth hormone deficiency with a normal bone age. Gene sequencing in the patient revealed a novel compound heterozygous mutation of c.5752A > C (Thr1918Pro) and c.500_501delTT (Phe167Cysfs*7) in the NBAS gene.

CONCLUSIONS

To our best knowledge, these novel mutations in the NBAS gene have not been reported. Normal bone age with growth hormone deficiency in this patient is different from the patients with SOPH syndrome that have been previously reported. These findings enrich the mutant spectrum of the NBAS gene and add our understanding of SOPH syndrome.

Acute Liver Failure: An Update

Pediatric acute liver failure (PALF) is a dynamic, life-threatening condition of disparate etiology. Management of PALF is dependent on intensive collaborative clinical care and support. Proper recognition and treatment of common complications of liver failure are critical to optimizing outcomes. In parallel, investigations to identify underlying cause and the implementation of timely, appropriate treatment can be life-saving. Predicting patient outcome in the era of liver transplantation has been unfulfilling and better predictive models must be developed for proper stewardship of the limited resource of organ availability.

A Learning Collaborative Approach Increases Specificity of Diagnosis of Acute Liver Failure in Pediatric Patients

BACKGROUND & AIMS

Many pediatric patients with acute liver failure (PALF) do not receive a specific diagnosis (such as herpes simplex virus or Wilson disease or fatty acid oxidation defects)-they are left with an indeterminate diagnosis and are more likely to undergo liver transplantation, which is contraindicated for some disorders. Strategies to facilitate complete diagnostic testing should increase identification of specific liver diseases and might reduce liver transplantation. We investigated whether performing recommended age-specific diagnostic tests (AS-DTs) at the time of hospital admission reduces the percentage PALFs with an indeterminate diagnosis.

METHODS

We performed a multinational observational cohort study of 658 PALF participants in the United States and Canada, enrolled at 10 medical centers, during 3 study phases from December 1999 through December 2014. A learning collaborative approach was used to implement AS-DT using an electronic medical record admission order set at hospital admission in phase 3 of the study. Data from 10 study sites participating in all 3 phases were compared before (phases 1 and 2) and after (phase 3) diagnostic test recommendations were inserted into electronic medical record order sets.

RESULTS

The percentage of subjects with an indeterminate diagnosis decreased significantly between phases 1-2 (48.0%) and phase 3 (to 30.8%) (P = .0003). The 21-day cumulative incidence rates for liver transplantation were significantly different among phase 1 (34.6%), phase 2 (31.9%), and phase 3 (20.2%) (P = .030). The 21-day cumulative incidence rates for death did not differ significantly among phase 1 (17.9%), phase 2 (11.9%), and phase 3 (11.3%) (P = .20).

CONCLUSIONS

In a multinational study of children with acute liver failure, we found that incorporating diagnostic test recommendations into electronic medical record order sets accessed at time of admission reduced the percentage with an indeterminate diagnosis that may have reduced liver transplants without increasing mortality. Widespread use of this approach could significantly enhance care of acute liver failure in children.

Liver Biopsy Can Be Safely Performed in Pediatric Acute Liver Failure to Aid in Diagnosis and Management

OBJECTIVES

Liver biopsy can be a valuable tool to help determine the etiology of pediatric acute liver failure (PALF), but is often not performed due to safety concerns. The primary aim was to describe the incidence of major complications after liver biopsy performed in the setting of PALF.

METHODS

Medical records from 2006 to 2016 were reviewed. Patients age 0 to 17 years, who met criteria for PALF, and had a liver biopsy performed while their international normalized ratio (INR) was ≥1.5 were included.

RESULTS

A total of 26 cases of liver biopsy in the setting of PALF were identified. The majority (n = 22, 85%) of patients had primary liver disease. Most biopsies (n = 17, 65%) were performed by the transjugular route, with 5 (19%) performed percutaneously under ultrasound guidance and 4 (15%) during a surgical procedure. Median INR before biopsy was 2.1 (IQR = 1.73-2.9). Blood products were given before or during the procedure in 23 (88%) cases. One patient (3.8%) had a major complication of biopsy-associated bleeding requiring a blood transfusion. An additional 3 patients had a hemoglobin decrease of 2.1 to 2.9 g/dL post-biopsy that was attributed to the procedure but no interventions were necessary. Biopsy results contributed to establishing a diagnosis in 62% (n = 16) of cases, and influenced treatment decisions in 9 of those cases.

CONCLUSIONS

Liver biopsy is safe in the majority of patients with PALF and associated with infrequent major complications. Clinicians should consider performing liver biopsy in this setting, especially when the transjugular approach is feasible, since findings may guide diagnosis and therapy.

Indeterminate pediatric acute liver failure is uniquely characterized by a CD103+ CD8+ T-cell infiltrate

The cause of pediatric acute liver failure (PALF) is unknown in up to 40% of cases. Evidence suggests that aberrant immune system activation may play a role. We hypothesized that indeterminate PALF cases would exhibit a unique pattern of hepatic inflammation. This was a retrospective and prospective study of PALF cases due to indeterminate (iPALF), autoimmune hepatitis, or known diagnosis (dPALF) etiology. Liver tissue sections were stained with immunohistochemical markers for cytotoxic T-cells (cluster of differentiation 8 [CD8]), perforin, and tissue resident memory T-cells (CD103) and scored as minimal, moderate, or dense. Lymphocytes were isolated from liver tissue for T-cell receptor beta sequencing and flow-cytometric studies. Thirty-three iPALF, 9 autoimmune hepatitis, and 14 dPALF cases were included. Dense hepatic infiltrates of CD8⁺ T-cells were found in 27 (82%) iPALF cases compared to 1 (7%) dPALF case (P < 0.0001). Perforin staining was dense or moderate in 19 (73%) of 26 iPALF cases compared to minimal in all 7 dPALF cases (P = 0.004); 16 (62%) of 26 iPALF cases had dense CD103 staining compared to none of the 6 dPALF cases (P = 0.001). T-cell receptor beta sequencing of iPALF cases demonstrated increased clonality compared to dPALF and control cases. Flow cytometry and immunohistochemistry revealed that iPALF intrahepatic leukocytes were predominantly tissue resident memory CD8⁺ T-cells.

CONCLUSION

Indeterminate PALF is characterized by a dense CD8⁺ T-cell hepatic infiltrate consistent with expansion of a tissue resident memory T-cell phenotype; CD8⁺ T-cells are a biomarker of immune dysregulation in iPALF and may be used to better identify and define this group. (Hepatology 2018).

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.

Liver involvement in kidney disease and vice versa

The liver and kidneys are often similarly affected by a single disease. This is the case in metabolic, immunological, toxic, and infectious diseases, and in the different congenital malformation syndromes. Also, an enzymatic defect in an otherwise healthy liver or the consequences of advanced liver disease by itself can cause kidney disease as a secondary phenomenon. In this review, we describe numerous pathogenic mechanisms leading to dysfunction or malformations of the liver and kidneys in children. We encourage multidisciplinary management for optimal care. A combined liver-kidney transplantation is sometimes needed.

Management of Acute Liver Failure: A Pediatric Perspective

Purpose of Review

Pediatric acute liver failure is a rare, complex, rapidly progressing, and life-threatening illness. Majority of pediatric acute liver failures have unknown etiology. This review intends to discuss the current literature on the challenging aspects of management of acute liver failure.

Recent Findings

Collaborative multidisciplinary approach for management of patients with pediatric acute liver failure with upfront involvement of transplant hepatologist and critical care specialists can improve outcomes of this fatal disease. Extensive but systematic diagnostic evaluation can help to identify etiology and guide management. Early referral to a transplant center with prompt liver transplant, if indicated, can lead to improved survival in these patients.

Summary

Prompt identification and aggressive management of pediatric acute liver failure and related comorbidities can lead to increased transplant-free survival and improved post-transplant outcomes, thus decreasing mortality and morbidity associated with this potential fatal condition.

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.

Profile and outcome of first 109 cases of paediatric acute liver failure at a specialized paediatric liver unit in India

BACKGROUND & AIMS

The outcome of paediatric acute liver failure largely depends on age and aetiology. The aim of this work was to study the aetiological spectrum and outcome of the paediatric acute liver failure cases.

METHODS

This prospective observational study included all children (<18 years age) fulfilling paediatric acute liver failure study group definition. Aetiological evaluation was done and predictive factors for poor outcome (death or liver transplantation) were analysed.

RESULTS

There were 109 children in total. The commonest aetiology was viral infections (50, 45.8%) followed by metabolic liver diseases (14, 13.2%) and drug-induced liver injury (12, 11%). Viral, indeterminate and drug-induced liver injury group were older in age, had higher international normalized ratio and alanine transaminases in comparison with those with metabolic liver diseases and other aetiologies (P<.05). At 90 days from presentation, 52 (47.7%) children survived with native liver. On multivariate analysis, jaundice to encephalopathy interval >7 days (adjusted OR: 9.16, 95% CI: 1.55-53) and higher paediatric/model for end-stage liver disease scores at 72 hours (adjusted OR: 1.2, 95% CI: 1.08-1.32) were associated with poor outcome.

CONCLUSION

Viral infections, indeterminate and drug-induced liver injury-related paediatric acute liver failure usually present in older children with higher international normalized ratio and alanine transaminases. Jaundice to encephalopathy interval >7 days and paediatric/model for end stage liver disease score >24 at 72 hours are associated with poor outcome.