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

The diagnosis and management of idiosyncratic drug-induced liver injury

Drug-induced liver injury (DILI) is an uncommon but important cause of liver disease that can arise after exposure to a multitude of drugs and herbal and dietary supplements. The severity of idiosyncratic DILI varies from mild serum aminotransferase elevations to the development of severe liver injury that can progress to acute liver failure resulting in death or liver transplantation within days of DILI onset. Chronic liver injury that persists for more than 6 months after DILI onset is also becoming increasingly recognized in up to 20% of DILI patients. Host demographic (age, gender, race), clinical and laboratory features at DILI onset have been associated with the severity and outcome of liver injury in DILI patients. In addition to cessation of the suspect drug, other medical interventions including the use of N-acetylcysteine and corticosteroids in selected patients have shown some clinical benefit, but additional prospective studies are needed. A number of promising diagnostic, prognostic and mechanistic serum and genetic biomarkers may help improve our understanding of the pathogenesis and treatment of idiosyncratic DILI.

Rodenticide Poisoning

How to cite this article: D'Silva C, Krishna B. Rodenticide Poisoning. Indian J Crit Care Med 2019;23(Suppl 4):S272–S277.

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.

A comparison of the effects of thymoquinone, silymarin and N-acetylcysteine in an experimental hepatotoxicity

This study investigated the effects of thymoquinone, silymarin, and N-acetylcysteine in a rat model with carbon tetrachloride (CCl₄)-induced hepatotoxicity. Although numerous similar studies are available, we aimed to compare the efficacy of these agents by considering N-acetylcysteine as a reference compound. A total of 50 male Wistar albino rats were randomly designated as 5 groups: Group I, CCl₄; group II, thymoquinone and CCl₄; group III, silymarin and CCl₄; group IV, N-acetylcysteine and CCl₄; group V, control group. CCl₄ was administered intraperitoneally at a dose of 1.5 mL/kg (a mixture of CCl₄: olive oil, 1:2) twice a week. Thymoquinone was administered at a dose of 10 mg/kg, silymarin was administered at a dose of 100 mg/kg, and N-acetylcysteine was administered at a dose of 100 mg/kg by daily intraperitoneal injection. At the end of four weeks, blood and liver tests were analyzed. The results were evaluated statistically via the one-way ANOVA test. A p-value <0.05 was considered statistically significant. Thymoquinone, silymarin, and N-acetylcysteine improved the levels of alanine aminotransferase, tumor necrosis factor-α, platelet-derived growth factor-BB, and interleukin-6, which were increased by CCl₄. Thymoquinone and silymarin showed the positive increase in liver glutathione levels. Thymoquinone, silymarin, and N-acetylcysteine improved blood total oxidant status. In the histological examinations of liver tissue, thymoquinone decreased necrosis, and inflammation. The most positive decrease in the α-smooth muscle actin-stained hepatic stellate cell count was only observed with thymoquinone. These findings suggest that thymoquinone, silymarin, and N-acetylcysteine have potential for the treatment of diseases causing liver injury. Among these agents, thymoquinone showed the best results on most of the parameters. Since TQ appears to be at least as effective as SM and NAC in our in-vitro study, we propose that it is time for clinical studies with thymoquinone on hepatotoxicity.

Nonacetaminophen Drug-Induced Acute Liver Failure

Acute liver failure of all causes is diagnosed in between 2000 and 2500 patients annually in the United States. Drug-induced acute liver failure is the leading cause of acute liver failure, accounting for more than 50% of cases. Nonacetaminophen drug injury represents 11% of all cases in the latest registry from the US Acute Liver Failure Study Group. Although rare, acute liver failure is clinically dramatic when it occurs, and requires a multidisciplinary approach to management. In contrast with acetaminophen-induced acute liver failure, non-acetaminophen-induced acute liver failure has a more ominous prognosis with a lower liver transplant-free survival.

Acute liver failure induced by idiosyncratic reaction to drugs: Challenges in diagnosis and therapy

Acute liver failure (ALF) requires urgent attention to identify etiology and determine prognosis, in order to assess likelihood of survival or need for transplantation. Identifying idiosyncratic drug-induced liver injury (iDILI) may be particularly difficult, but the illness generally follows a subacute course, allowing time to assess outcome and find a liver graft if needed. Not all drugs that cause iDILI lead to ALF; the most common are antibiotics including anti-tuberculous medications, non-steroidal anti-inflammatory agents and herbal and dietary supplements (HDS). Determining causality remains challenging particularly if altered mentation is present; identifying the causative agent depends in part on knowing the propensity of the drugs that have been taken in the proper time interval, plus excluding other causes. In general, iDILI that reaches the threshold of ALF will more often than not require transplantation, since survival without transplant is around 25%. Treatment consists of withdrawal of the presumed offending medication, consideration of N-acetylcysteine (NAC), as well as intensive care. Corticosteroids have not proven useful except perhaps in instances of apparent autoimmune hepatitis caused by a limited number of agents. Recently developed prognostic scoring systems may also aid in predicting outcome in this setting.

Drug idiosyncrasy due to pirfenidone presenting as acute liver failure: Case report and mini-review of the literature

Idiosyncratic drug‐induced liver injury (DILI) is ranked among the top most common etiologies of acute liver failure (ALF). It carries poor transplant‐free survival. Pirfenidone is an anti‐inflammatory and antifibrotic drug that is commonly used for the treatment of idiopathic pulmonary fibrosis (IPF). Hepatotoxicity due to pirfenidone is rare and generally manifests as a mild rise in serum aminotransferases. In this mini‐review, we report an unusual case of idiosyncratic DILI due to pirfenidone presenting as ALF, with emphasis on the definition, classification, diagnostic criteria, histopathology, molecular markers, and treatment options for DILI and related ALF. A 77‐year‐old man with known Parkinson's disease and IPF presented with jaundice for 7 days and altered mental status for 4 days. His long‐term medications included a levodopa/carbidopa combination with a recent addition of pirfenidone over the previous 1 month; there was no monitoring of liver function tests. The evaluation suggested features of acute liver failure with grade III hepatic encephalopathy, acute kidney injury, and metabolic acidosis. The diagnostic workup ruled out viral, toxic, ischemic, and other etiologies for acute liver failure. Based on a Roussel Uclaf Causality Assessment Method score of 7 and possible DILI‐ALF, pirfenidone was withdrawn. He was evaluated for liver transplantation but was declined. Despite all supportive measures in intensive care, organ failure progressed and he succumbed to the illness on day 4. Postmortem liver biopsy revealed findings consistent with DILI (final Roussel Uclaf Causality Assessment score, 10). Conclusion: DILI‐ALF carries poor prognosis, and liver transplantation should be considered early in the course. Characterization, reporting, monitoring, and labeling of pirfenidone‐related hepatotoxicity is vital given its common use in IPF. (Hepatology Communications 2018;2:142–147)

Antiepileptic Drugs and Liver Disease

Acute, symptomatic seizures or epilepsy may complicate the course of hepatic disease. Choosing the most appropriate antiepileptic drug in this setting represents a difficult challenge, as most medications are metabolized by the liver. This article focuses on the acute and chronic treatment of seizures in patients with advanced liver disease and reviews the hepatotoxic potential of specific antiepileptic drugs. Newer antiepileptic drugs without, or with minimal, hepatic metabolism, such as levetiracetam, lacosamide, topiramate, gabapentin, and pregabalin should be used as first-line therapy. Medications undergoing extensive hepatic metabolism, such as valproic acid, phenytoin, and felbamate should be used as drugs of last resort. In special circumstances, as in patients affected by acute intermittent porphyria, exposure to most antiepileptic drugs could precipitate attacks. In this clinical scenario, bromides, levetiracetam, gabapentin, and vigabatrin constitute safe choices. For the treatment of status epilepticus, levetiracetam and lacosamide, available in intravenous preparations, are good second-line therapies after benzodiazepines fail to control seizures. Hepatotoxicity is also a rare and unexpected side effect of some antiepileptic drugs. Drugs such as valproic acid, phenytoin, and felbamate, have a well-recognized association with liver toxicity. Other antiepileptic drugs, including phenobarbital, benzodiazepines, ethosuximide, and the newer generations of antiepileptic drugs, have only rarely been linked to hepatotoxicity. Thus physicians should be mindful of the pharmacokinetic profile and the hepatotoxic potential of the different antiepileptic drugs available to treat patients affected by liver disease.

Acute Liver Failure

Acute liver failure (ALF) is a life-threatening condition of heterogeneous etiology. Outcomes are better with early recognition and prompt initiation of etiology-specific therapy, intensive care protocols, and liver transplantation (LT). Prognostic scoring systems include the King's College Criteria and Model for End-stage Liver Disease score. Cerebral edema and intracranial hypertension are reasons for high morbidity and mortality; hypertonic saline is suggested for patients with a high risk for developing intracranial hypertension, and when it does, mannitol is recommended as first-line therapy. Extracorporeal liver support system may serve as a bridge to LT and may increase LT-free survival in select cases.

NBAS mutations cause acute liver failure: when acetaminophen is not a culprit

Background

Pediatric acute-liver-failure due to acetaminophen (APAP) administration at therapeutic dosage is rare, while viral infections and metabolic defects are the prevalent causes. Yet, as acetaminophen is routinely used in febrile illnesses, it may be mistakenly held responsible for the acute liver damage.

Case presentation

An 11 month old boy had been on acetaminophen for 10 days (total dose 720 mg = 72 mg/kg) when he developed acute-liver-failure with encephalopathy. As he rapidly improved on N-acetylcysteine (NAC) infusion, it was concluded that chronic acetaminophen administration in an infant had lead to acute-liver-failure even at therapeutic doses, that N-acetylcysteine infusion had been life-saving and should be immediately started in similar circumstances. The child, however, had two further episodes of acute liver damage over a 34-month period, without having been given acetaminophen, as the parents carefully avoided using it. His clinical, laboratory and radiological findings between the acute episodes were unremarkable. His features and skeletal surveys were not suggestive of a syndromic condition. He then went on to suffer another episode of acute-liver-failure with multi-organ failure, necessitating an urgent liver transplant. All efforts to come to a diagnosis for the causes of his recurrent episodes of liver failure had been unsuccessful, until a biallelic mutation in the NBAS gene was reported to be associated with recurrent acute-liver-failure in children. The boy’s DNA analysis revealed compound heterozygous pathogenic mutations in the NBAS gene. Liver failure episodes in these patients are triggered and worsened by fever, most likely due to thermal susceptibility of hepatocytes, hence APAP, rather than being a culprit, is part of the supportive treatment.

Conclusions

We suggest that, in acute-liver-failure with a history of acetaminophen exposure at therapeutic dosage, clinicians should not be contented with administering NAC, but should consider an alternative etiology, above all if the episodes are recurrent, and actively start supportive and antipyretic treatment while seeking the advice of a specialist unit.

Pediatric liver failure: we came, we saw, but have we conquered?

Although there have been advances made in the diagnosis and management of pediatric acute liver failure, there is still no consensus regarding the definition or standardized evaluation, and an inability to predict outcomes, specifically irreversible brain injury, in many patients exists. Much of the research surrounding pediatric acute liver failure in the last several years has centered on the development of predictive scoring systems to enhance diagnosis and treatment decisions. In this article, we will discuss our current understanding of liver failure and updated management strategies in children with acute liver failure.

Idiosyncratic drug-induced liver injury: A short review

Idiosyncratic drug‐induced liver injury (iDILI) is a rare adverse drug reaction that occasionally leads to acute liver failure or even death. An aging population that uses more drugs, a constant influx of newly developed drugs, and a growing risk from herbal and dietary supplements of uncertain quality can lead to an increase in iDILI. Antimicrobials, central nervous system agents, and herbal and dietary supplements are the most common causes of iDILI in developed countries. iDILI is still a diagnosis of exclusion, and thus careful history taking and thorough work‐ups for competing etiologies, such as acute viral hepatitis, autoimmune hepatitis, and others, are essential. The pathogenesis of iDILI is not clear and includes a mix of host reactions, drug metabolites, and environmental factors. Immediate cessation of the suspected offending drug is key to preventing or minimizing progressive damage. No definitive therapies for iDILI are available, and the treatments remain largely supportive. (Hepatology Communications 2017;1:494–500)

EASL Clinical Practical Guidelines on the management of acute (fulminant) liver failure

The term acute liver failure (ALF) is frequently applied as a generic expression to describe patients presenting with or developing an acute episode of liver dysfunction. In the context of hepatological practice, however, ALF refers to a highly specific and rare syndrome, characterised by an acute abnormality of liver blood tests in an individual without underlying chronic liver disease. The disease process is associated with development of a coagulopathy of liver aetiology, and clinically apparent altered level of consciousness due to hepatic encephalopathy. Several important measures are immediately necessary when the patient presents for medical attention. These, as well as additional clinical procedures will be the subject of these clinical practice guidelines.

Intensive Care Management of Pediatric Acute Liver Failure

Pediatric acute liver failure is rare but life-threatening illness that occurs in children without preexisting liver disease. The rarity of the disease, along with its severity and heterogeneity, presents unique clinical challenges to the physicians providing care for pediatric patients with acute liver failure. In this review, practical clinical approaches to the care of critically ill children with acute liver failure are discussed with an organ system-specific approach. The underlying pathophysiological processes, major areas of uncertainty, and approaches to the critical care management of pediatric acute liver failure are also reviewed.

Role of N-acetylcysteine treatment in non-acetaminophen-induced acute liver failure: A prospective study

BACKGROUND/AIMS

Acute liver failure (ALF) is a rare but severe medical emergency. To date, there is no established treatment for non-acetaminophen-induced acute liver failure (NAI-ALF) other than liver transplantation, and little is known about the use of N-acetylcysteine (NAC) in NAI-ALF. A randomized case control study was conducted with the aim to determine the effect of NAC on the mortality of NAI-ALF patients, as well as to evaluate the safety and efficacy of NAC use.

PATIENTS AND METHODS

A total of 80 patients diagnosed with NAI-ALF were included in the study. Forty patients received NAC infusion for 72 h whereas the control group received placebo. The variables evaluated were demographic characteristics, signs and symptoms, biochemical parameters, and clinical course during hospitalization.

RESULTS

The two groups (NAC and control) were comparable for various baseline characteristics (such as etiology of ALF, INR, alanine aminotransferase, creatinine, albumin, and grade of encephalopathy), except for age. Although majority of patients had undetermined etiology (32.5% in NAC group and 42.5% in control group), the second main cause was acute hepatitis E and drug or toxin-induced ALF. The mortality decreased to 28% with the use of NAC versus 53% in the control group (P = 0.023). The use of NAC was associated with shorter length of hospital stay in survived patients (P = 0.002). Moreover, the survival of patients was improved by NAC (P = 0.025). Also, drug-induced ALF showed improved outcome compared to other etiologies.

CONCLUSION

The findings of the study recommend the use of NAC along with conventional treatments in patients with NAI-ALF in non-transplant centers while awaiting referrals and conclude the use of NAC as safe.

Drug-induced liver injury: Do we know everything?

Interest in drug-induced liver injury (DILI) has dramatically increased over the past decade, and it has become a hot topic for clinicians, academics, pharmaceutical companies and regulatory bodies. By investigating the current state of the art, the latest scientific findings, controversies, and guidelines, this review will attempt to answer the question: Do we know everything? Since the first descriptions of hepatotoxicity over 70 years ago, more than 1000 drugs have been identified to date, however, much of our knowledge of diagnostic and pathophysiologic principles remains unchanged. Clinically ranging from asymptomatic transaminitis and acute or chronic hepatitis, to acute liver failure, DILI remains a leading causes of emergent liver transplant. The consumption of unregulated herbal and dietary supplements has introduced new challenges in epidemiological assessment and clinician management. As such, numerous registries have been created, including the United States Drug-Induced Liver Injury Network, to further our understanding of all aspects of DILI. The launch of LiverTox and other online hepatotoxicity resources has increased our awareness of DILI. In 2013, the first guidelines for the diagnosis and management of DILI, were offered by the Practice Parameters Committee of the American College of Gastroenterology, and along with the identification of risk factors and predictors of injury, novel mechanisms of injury, refined causality assessment tools, and targeted treatment options have come to define the current state of the art, however, gaps in our knowledge still undoubtedly remain.

Fulminant Liver Failure in a Child With β-Thalassemia on Deferasirox: A Case Report

Deferesirox (DFX), an oral chelating agent, is used to treat chronic iron overload in several hematological diseases such as β-thalassemia, sickle cell disease, and myelodysplastic anemia. DFX is generally well tolerated with the exception of gastrointestinal disturbances and rash, although cases of renal toxicity, as well as acute and chronic liver failure, have been reported in adults and children. Here we describe a 3-year-old girl with β-thalassemia undergoing treatment with DFX who presented with acute liver failure and Fanconi's syndrome. It is important for pediatric gastroenterologists, hepatologists, and hematologists to be aware that the commonly used drug DFX can lead to acute liver failure in children, and liver function should be monitored closely in all patients taking DFX.

Lactate and Lactate: Pyruvate Ratio in the Diagnosis and Outcomes of Pediatric Acute Liver Failure

OBJECTIVES

To assess the accuracy of blood lactate and lactate: pyruvate molar ratio (L:P) as a screen for mitochondrial, respiratory chain, or fatty acid oxidation disorders in children with pediatric acute liver failure (PALF); to determine whether serum lactate ≥ 2.5 mmol/L or L:P  ≥ 25 correlated with biochemical variables of clinical severity; and to determine whether lactate or L:P is associated with clinical outcome at 21 days.

STUDY DESIGN

Retrospective review of demographic, clinical, laboratory, and outcome data for PALF study group participants who had lactate and pyruvate levels collected on the same day.

RESULTS

Of 986 participants, 110 had lactate and pyruvate levels collected on the same day. Of the 110, the etiology of PALF was a mitochondrial disorder in 8 (7%), indeterminate in 65 (59%), and an alternative diagnosis in 37 (34%). Lactate, pyruvate, and L:P were similar among the 3 etiologic groups. There was no significant association between the initial lactate or L:P and biochemical variables of clinical severity or clinical outcome at 21 days.

CONCLUSIONS

A serum lactate ≥ 2.5 mmol/L and/or elevated L:P was common in all causes of PALF, not limited to those with a mitochondrial etiology, and did not predict 21-day clinical outcome.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00986648.

Pediatric acute liver failure of undetermined cause: A research workshop

Pediatric acute liver failure (PALF) is a potentially devastating condition that occurs in previously healthy children of all ages and frequently leads to a rapid clinical deterioration. An identified cause for liver injury is lacking in approximately 30% of cases. Children with undetermined diagnosis have lower spontaneous survival and higher rates of transplantation and death than other diagnostic groups. A single-day workshop sponsored by the National Institute of Diabetes and Digestive and Kidney Diseases brought together clinicians and basic scientists to integrate aligned research findings and develop a foundation for new mechanistic studies and future treatment trials. The clinical phenotype of indeterminate PALF shares important similarities to the hyperinflammatory state characteristic of hemophagocytic lymphohistiocytosis (HLH) and macrophage activation syndrome (MAS). A failure of cytotoxic T cells to limit or contract inflammatory responses may propagate injury and lead to a local and systemic milieu that does not support normal hepatic regeneration. Evidence was presented that bone marrow (BM)-derived Sinusoidal endothelial cell PROgenitor Cells (sprocs) play a vital role in hepatic regeneration. Overwhelming systemic inflammatory responses may suppress mobilization of BM sprocs and dampen hepatic recovery.

CONCLUSION

Experience gained through treatment trials of HLH and MAS in childhood may inform study design for therapy of PALF. Successful approaches to limiting neuroinflammation through reduction of systemic inflammation and standardized neuroprotection protocols that limit glial injury could significantly improve intact survival. Finally, given that PALF is a rare disease, investigative efforts must include broad multicenter collaboration and careful stewardship of biorepository specimens. (Hepatology 2017;65:1026-1037).

Management of Acute Hepatotoxicity Including Medical Agents and Liver Support Systems

Drug-induced liver injury (DILI) can be predictable or idiosyncratic and has an estimated incidence of approximately 20 cases per 100,000 persons per year. DILI is a common cause of acute liver failure in the United States. No accurate tests for diagnosing DILI exist, and its diagnosis is based on exclusion of other conditions. Managing DILI includes discontinuing the suspected causative agent and in selected cases administering an antidote. Liver support systems are used for long-term support or as a bridge to transplantation and are effective for improving encephalopathy, hyperbilirubinemia, and other liver-related conditions, but whether they improve survival remains uncertain.

Adverse Drug Reactions: Type A (Intrinsic) or Type B (Idiosyncratic)

Hepatotoxic adverse drug reactions are associated with significant morbidity and mortality and are the leading cause of postmarketing regulatory action in the United States. They are classified as Type A (intrinsic) or Type B (idiosyncratic). Type A are predictable, dose-related toxicities, often identified in preclinical or clinical trials, and usually occur in overdose settings or with pre-existing hepatic impairment. Type B are not clearly related to increasing dose and are associated with drug-specific and patient-specific characteristics and environmental risks. Rare Type B reactions are often identified postmarketing. Identification and management, including electronic resources, has evolved.

Acute Liver Failure

Pediatric acute liver failure (ALF) is a complex and rapidly progressive syndrome that results from a variety of age-dependent etiologies. It is defined by the acute onset of liver disease with no evidence of chronic liver disease. There must be biochemical or clinical evidence of severe liver dysfunction as defined by an international normalized ratio (INR) ≥2. If hepatic encephalopathy is present, INR should be ≥1.5. Unfortunately, due to the rarity of ALF in pediatric patients, there is a paucity of diagnostic and management algorithms and each patient must have an individualized approach. [Pediatr Ann. 2016;45(12):e433-e438.].

Acute and Fatal Isoniazid-Induced Hepatotoxicity: A Case Report and Review of the Literature

This paper describes a case of an acute and fatal isoniazid-induced hepatotoxicity and provides a review of the literature. A 65-year-old female diagnosed with latent Mycobacterium tuberculosis infection was receiving oral isoniazid 300 mg daily. She was admitted to the hospital for epigastric and right sided flank pain of one-week duration. Laboratory results and imaging confirmed hepatitis. After ruling out all other possible causes, she was diagnosed with isoniazid-induced acute hepatitis (probable association by the Naranjo scale). After discharge, the patient was readmitted and suffered from severe coagulopathy, metabolic acidosis, acute kidney injury, hepatic encephalopathy, and cardiorespiratory arrest necessitating two rounds of cardiopulmonary resuscitation. Despite maximal hemodynamic support, the patient did not survive. A review of the literature, from several European countries and the United States of America, revealed a low incidence of mortality due to isoniazid-induced hepatotoxicity when used as a single agent for latent Mycobacterium tuberculosis infection. As for the management, the first step consists of withdrawing isoniazid and rechallenge is usually discouraged. Few treatment modalities have been proposed; however there is no robust evidence to support any of them. Routine monitoring for hepatotoxicity in patients receiving isoniazid is warranted to prevent morbidity and mortality.

The changing face of liver transplantation for acute liver failure: Assessment of current status and implications for future practice

The etiology and outcomes of acute liver failure (ALF) have changed since the definition of this disease entity in the 1970s. In particular, the role of emergency liver transplantation has evolved over time, with the development of prognostic scoring systems to facilitate listing of appropriate patients, and a better understanding of transplant benefit in patients with ALF. This review examines the changing etiology of ALF, transplant benefit, outcomes following transplantation, and future alternatives to emergency liver transplantation in this devastating condition.

Clinical Course among Cases of Acute Liver Failure of Indeterminate Diagnosis

OBJECTIVE

To investigate the heterogeneity in clinical course among those with pediatric acute liver failure (PALF) of indeterminate disease etiology.

STUDY DESIGN

We studied participants enrolled in the PALF registry study with indeterminate final diagnosis. Growth mixture modeling was used to analyze participants' international normalized ratio, total bilirubin, and hepatic encephalopathy trajectories in the first 7 days following enrollment. Participants with at least 3 values for 1 or more of the measurements were included. We examined the association between the resulting latent subgroup classification with participants' characteristics and disease outcomes. Data from participants with PALF of specified etiologies were used to investigate the potential diagnostic value of the latent subgroups.

RESULTS

In this sample of 380 participants with indeterminate final diagnosis, 115 (30%) experienced mild and quickly improving disease trajectories and another 48 (13%) started with severe disease but improved by day 7. The majority of participants (216, 57%) had disease trajectories that worsened over time. The identified patterns of disease trajectories are predictive of outcome (P < .001). The trajectory patterns are associated with the underlying disease etiology (P < .001) for the 488 participants with PALF of specified etiologies.

CONCLUSIONS

The clinical courses of participants with PALF of indeterminate disease etiology exhibit distinct trajectory patterns, which have important prognostic and potentially diagnostic value.

N-acetylcysteine for non-paracetamol drug-induced liver injury: a systematic review

AIMS

N-acetylcysteine (NAC) may be useful in the management of non-paracetamol drug-induced liver injury (DILI). Our objective was to review systematically evidence for the use of NAC as a therapeutic option for non-paracetamol DILI.

METHODS

We searched for randomized controlled trials (RCTs) and prospective cohort studies. We searched several bibliographic databases, grey literature sources, conference proceedings and ongoing trials. Our pre-specified primary outcomes were all cause and DILI related mortality, time to normalization of liver biochemistry and adverse events. Secondary outcomes were proportion receiving liver transplant, time to transplantation, transplant-free survival and hospitalization duration.

RESULTS

We identified one RCT of NAC vs. placebo in patients with non-paracetamol acute liver failure. There was no difference in the primary outcomes of overall survival at 3 weeks between NAC [70%, 95% confidence interval (CI) = 60%, 81%, n = 81] and placebo (66%, 95% CI = 56%, 77%, n = 92). NAC significantly improved the secondary outcomes of transplant-free survival compared with placebo: 40% NAC (95% CI = 28%, 51%) vs. 27% placebo (95% CI = 18%, 37%). A subgroup analysis according to aetiology found improved transplant-free survival in patients with non-paracetamol DILI, NAC (58%, n = 19) vs. placebo (27%, n = 26), odds ratio (OR) 0.27 (95% CI = 0.076, 0.942). Overall survival was similar, NAC (79%) vs. placebo (65%);, OR 0.50 (95% CI = 0.13, 1.98).

CONCLUSION

Current available evidence is limited and does not allow for any firm conclusions to be made regarding the role of NAC in non-paracetamol DILI. We therefore highlight the need for further research in this area.

Resolution of norfloxacin-induced acute liver failure after N-acetylcysteine therapy: further support for the use of NAC in drug-induced ALF?

Liver injury due to idiosyncratic drug reactions can be difficult to diagnose and may lead to acute liver failure (ALF), which has a high mortality rate. N-acetylcysteine (NAC) is effective treatment for paracetamol toxicity, but its role in non-paracetamol drug-induced ALF is controversial. We report on the use of a validated bedside tool to establish causality for drug-induced liver injury (DILI) and describe the first case of resolution of norfloxacin-induced ALF after NAC therapy. NAC is easy to administer and generally has a good safety profile. We discuss the evidence to support the use of NAC in ALF secondary to DILI and possibilities for further clinical research in this field.

Current and future directions in the treatment and prevention of drug-induced liver injury: a systematic review

While the pace of discovery of new agents, mechanisms and risk factors involved in drug-induced liver injury (DILI) remains brisk, advances in the treatment of acute DILI seems slow by comparison. In general, the key to treating suspected DILI is to stop using the drug prior to developing irreversible liver failure. However, predicting when to stop is an inexact science, and commonly used ALT monitoring is an ineffective strategy outside of clinical trials. The only specific antidote for acute DILI remains N-acetylcysteine (NAC) for acetaminophen poisoning, although NAC is proving to be beneficial in some cases of non-acetaminophen DILI in adults. Corticosteroids can be effective for DILI associated with autoimmune or systemic hypersensitivity features. Ursodeoxycholic acid, silymarin and glycyrrhizin have been used to treat DILI for decades, but success remains anecdotal. Bile acid washout regimens using cholestyramine appear to be more evidenced based, in particular for leflunomide toxicity. For drug-induced acute liver failure, the use of liver support systems is still investigational in the United States and emergency liver transplant remains limited by its availability. Primary prevention appears to be the key to avoiding DILI and the need for acute treatment. Pharmacogenomics, including human leukocyte antigen genotyping and the discovery of specific DILI biomarkers offers significant promise for the future. This article describes and summarizes the numerous and diverse treatment and prevention modalities that are currently available to manage DILI.

Potential targeted therapies for the inflammatory pathogenesis of hepatic encephalopathy

Hepatic encephalopathy (HE) is a severe neuropsychiatric complication of acute and chronic liver dysfunction, and is characterized by a spectrum that ranges from mild neuropsychological disturbances to coma. Although ammonia plays a critical role in the pathogenesis of HE, the plasma concentrations of ammonia and manifest symptoms of HE are not always consistent in patients with HE. Recently, a substantial body of evidence has indicated that inflammation acts in concert with ammonia in the pathogenesis of HE. Meanwhile, emerging novel and potential therapeutic strategies, including N-acetylcysteine, hypothermia, minocycline, non-steroidal anti-inflammatory drugs, tumour necrosis factor-alpha antagonists and p38 inhibitors, have been reported to ameliorate systemic inflammation and neuroinflammation, improve or reverse neuropsychiatric manifestations, and prevent the onset and progression of HE in patients and/or animal models of acute or chronic liver failure. These results point to the possible therapeutic utility of decreasing inflammation in the treatment of HE, and translation of these experimental results to the clinic may provide novel and promising therapeutic approaches for patients with HE secondary to acute or chronic liver failure. This review will provide an overview of these potential targeted therapies in the prophylaxis and treatment of HE.

Use of Pediatric Health Information System database to study the trends in the incidence, management, etiology, and outcomes due to pediatric acute liver failure in the United States from 2008 to 2013

Data were collected of children admitted with ALF to 16 US pediatric liver transplant centers from 2008 to 2013 using the PHIS for a retrospective analysis of PALF trends. Patient data linked to the principal diagnosis code for acute necrosis of the liver (570.00) were analyzed for the following: demographics, regional differences, changes over time, pharmaceutical trends, procedural trends, associated diagnoses, and patient outcomes. In 52.5% of 583 patients who met the selection criteria for PALF, the etiology remained undetermined. Acetaminophen toxicity (18.7%) was the most common identifiable etiology, and hepatic encephalopathy (38.6%) was the most common complication. Mortality was lower than previously reported; 95.4% survived and 73.2% survived without a liver transplant. Acute respiratory failure (OR = 3.4, p = 0.035), acute kidney injury (OR = 3.6, p = 0.003), and cerebral edema (OR = 3.6, p = 0.02) were independently associated with increased risk of mortality. The use of N-acetylcysteine in non-acetaminophen-related ALF, the use of intracranial pressure monitoring, and the proportion of sepsis decreased significantly during the study period. The PHIS database can be a useful tool to study the future trends of PALF patients.

The Art and Science of Diagnosing and Managing Drug-induced Liver Injury in 2015 and Beyond

Drug-induced liver injury (DILI) remains a leading reason why new compounds are dropped from further study or are the subject of product warnings and regulatory actions. Hy's Law of drug-induced hepatocellular jaundice causing a case-fatality rate or need for transplant of 10% or higher has been validated in several large national registries, including the ongoing, prospective U.S. Drug-Induced Liver Injury Network. It serves as the basis for stopping rules in clinical trials and in clinical practice. Because DILI can mimic all known causes of acute and chronic liver disease, establishing causality can be difficult. Histopathologic findings are often nonspecific and rarely, if ever, considered pathognomonic. A daily drug dose >50-100 mg is more likely to be hepatotoxic than does <10 mg, especially if the compound is highly lipophilic or undergoes extensive hepatic metabolism. The quest for a predictive biomarker to replace alanine aminotransferase is ongoing. Markers of necrosis and apoptosis such as microRNA-122 and keratin 18 may prove useful in identifying patients at risk for severe injury when they initially present with a suspected acetaminophen overdose. Although a number of drugs causing idiosyncratic DILI have HLA associations that may allow for pre-prescription testing to prevent hepatotoxicity, the cost and relatively low frequency of injury among affected patients limit the current usefulness of such genome-wide association studies. Alanine aminotransferase monitoring is often recommended but has rarely been shown to be an effective method to prevent serious DILI. Guidelines on the diagnosis and management of DILI have recently been published, although specific therapies remain limited. The LiverTox Web site has been introduced as an interactive online virtual textbook that makes the latest information on more than 650 agents available to clinicians, regulators, and drug developers alike.

Efficacy and safety of acetylcysteine in "non-acetaminophen" acute liver failure: A meta-analysis of prospective clinical trials

BACKGROUND

Acute liver failure (ALF) is a rare but highly mortal condition without liver transplantation (LT). N-acetylcysteine (NAC), a glutathione precursor that detoxifies the reactive metabolite of acetaminophen and replenishes hepatic glutathione stores, is a highly effective drug for the prevention of ALF caused by acetaminophen. However, therapeutic use of NAC in non-acetaminophen-induced ALF (NAI-ALF) including alcohol intoxication, hepatitis virus infection, or drug and toxin-related hepatotoxicity is still inconclusive. The aim of this article is using meta-analysis method to analyze recent prospective clinical trials for the safety and efficacy of NAC in patients with ALF not caused by acetaminophen poisoning.

METHODS

Prospective clinical trials comparing efficacy and safety between NAC and control in the treatment of NAI-ALF were identified by searching Pubmed (2000-2014) and EMBASE (2000-2014) using the search terms acetylcysteine or NAC and NAI-ALF. The primary outcome was overall survival. Secondary outcomes included liver transplantation-free survival, post transplantation survival, length of ICU and hospital stays, and the relationship with coma grade. The safety profiles were also analyzed.

RESULTS

Four clinical trials were selected for meta-analysis. A total of 331 patients receiving treatment with NAC (oral or intravenously) and 285 patients in control group were included for meta-analysis. No statistical difference was identified between NAC group and control group for overall survival [236/331 (71%) vs 191/285 (67%); 95% CI 1.16 (0.81-1.67); P=0.42]. However, there were significant differences between NAC group and control group regarding the survival with native liver [112/273 (41%) vs 68/226 (30%); 95% CI 1.61 (1.11-2.34); P=0.01] and post-transplantation survival [78/91 (85.7%) vs 50/70 (71.4%); 95% CI 2.44 (1.11-5.37); P=0.03]. The identified side effects of NAC included nausea, vomiting, and diarrhea or constipation. Rarely, it could cause rashes, fever, headache, drowsiness, low blood pressure, and elevated serum transaminase levels in a patient with cystic fibrosis. At the dose used for acetaminophen toxicity, acetylcysteine does not have hepatotoxic effects.

CONCLUSION

NAC is safe for NAI-ALF. It can prolong patients' survival with native liver without transplantation and survival after transplantation, but it cannot improve the overall survival.

Acetaminophen Adducts Detected in Serum of Pediatric Patients With Acute Liver Failure

OBJECTIVES

Previous studies in patients with acute liver failure identified acetaminophen (APAP) protein adducts in the serum of 12% and 19% of children and adults, respectively, with acute liver failure of indeterminate etiology. This article details the testing of APAP adducts in a subset (n = 393) of patients with varied diagnoses in the Pediatric Acute Liver Failure Study Group (PALFSG).

METHODS

Serum samples were available from 393 participants included in the PALFSG registry. Adduct measurement was performed using validated methods. Participants were grouped by diagnostic category as known APAP overdose, known other diagnosis, and indeterminate etiology. Demographic and clinical characteristics and participant outcomes were compared by adduct status (positive or negative) within each group.

RESULTS

APAP adduct testing was positive in 86% of participants with known APAP overdose, 6% with other known diagnoses, and 11% with an indeterminate cause of liver failure. Adduct-positive participants were noted to have marked elevation of serum alanine aminotransferase and aspartate aminotransferase coupled with total serum bilirubin that was significantly lower than adduct-negative patients. In the indeterminate group, adduct-positive patients had different outcomes than adduct-negative patients (P = 0.03); spontaneous survival was 16 of 21 (76%) in adduct-positive patients versus 75 of 169 (44%) in adduct-negative patients. Prognosis did not vary by adduct status in patients with known diagnoses.

CONCLUSIONS

Furthermore, study is needed to understand the relation of APAP exposure, as determined by the presence of APAP adducts, to the clinical phenotype and outcomes of children with acute liver failure.

The Reg3α (HIP/PAP) Lectin Suppresses Extracellular Oxidative Stress in a Murine Model of Acute Liver Failure

BACKGROUND AND AIMS

Acute liver failure (ALF) is a rapidly progressive heterogeneous illness with high mortality rate and no widely accessible cure. A promising drug candidate according to previous preclinical studies is the Reg3α (or HIP/PAP) lectin, which alleviates ALF through its free-radical scavenging activity. Here we study the therapeutic targets of Reg3α in order to gain information on the nature of the oxidative stress associated with ALF.

METHODS

Primary hepatocytes stressed with the reactive oxygen species (ROS) inducers TNFα and H2O2 were incubated with a recombinant Reg3α protein. ALF was induced in C57BL/6J mice by an anti-CD95 antibody. Livers and primary hepatocytes were harvested for deoxycholate separation of cellular and extracellular fractions, immunostaining, immunoprecipitation and malondialdehyde assays. Fibrin deposition was studied by immunofluorescence in frozen liver explants from patients with ALF.

RESULTS

Fibrin deposition occurs during experimental and clinical acute liver injuries. Reg3α bound the resulting transient fibrin network, accumulated in the inflammatory extracellular matrix (ECM), greatly reduced extracellular ROS levels, and improved cell viability. Hepatocyte treatment with ligands of death receptors, e.g. TNFα and Fas, resulted in a twofold increase of malondialdehyde (MDA) level in the deoxycholate-insoluble fractions. Reg3α treatment maintained MDA at a level similar to control cells and thereby increased hepatocyte survival by 35%. No antioxidant effect of Reg3α was noted in the deoxycholate-soluble fractions. Preventing fibrin network formation with heparin suppressed the prosurvival effect of Reg3α.

CONCLUSIONS

Reg3α is an ECM-targeted ROS scavenger that binds the fibrin scaffold resulting from hepatocyte death during ALF. ECM alteration is an important pathogenic factor of ALF and a relevant target for pharmacotherapy.

Acute liver failure in dogs and cats

OBJECTIVE

To define acute liver failure (ALF), review the human and veterinary literature, and discuss the etiologies and current concepts in diagnostic and treatment options for ALF in veterinary and human medicine.

ETIOLOGY

In veterinary medicine ALF is most commonly caused by hepatotoxin exposure, infectious agents, inflammatory diseases, trauma, and hypoxic injury.

DIAGNOSIS

A patient may be deemed to be in ALF when there is a progression of acute liver injury with no known previous hepatic disease, the development of hepatic encephalopathy of any grade that occurs within 8 weeks after the onset of hyperbilirubinemia (defined as plasma bilirubin >50 μM/L [>2.9 mg/dL]), and the presence of a coagulopathy. Diagnostic testing to more specifically characterize liver dysfunction or pathology is usually required.

THERAPY

Supportive care to aid the failing liver and compensate for the lost functions of the liver remains the cornerstone of care of patients with ALF. Advanced therapeutic options such as extracorporeal liver assist devices and transplantation are currently available in human medicine.

PROGNOSIS

The prognosis for ALF depends upon the etiology, the degree of liver damage, and the response to therapy. In veterinary medicine, the prognosis is generally poor.

N-acetylcysteine treats intravenous amiodarone induced liver injury

We report a case of intravenous (IV) amiodarone drug induced liver injury (DILI). The patient received IV N-acetylcysteine (NAC) which resulted in a rapid improvement in liver enzymes. While the specific mechanisms for the pathogenesis of IV amiodarone DILI and the therapeutic action of IV NAC are both unknown, this case strongly implies at least some commonality. Because IV amiodarone is indicated for the treatment of serious cardiac arrhythmias in an intensive care unit setting, some degree of ischemic hepatitis is likely a cofactor in most cases.

Paracetamol-associated acute liver failure in Australian and New Zealand children: high rate of medication errors

BACKGROUND

In children, paracetamol overdose due to deliberate self-poisoning, accidental exposure or medication errors can lead to paediatric acute liver failure and death. In Australia and New Zealand, the nature of ingestion and outcomes of paracetamol-associated paediatric acute liver failure have not been described.

OBJECTIVE

To describe the nature and outcomes of paracetamol-associated paediatric acute liver failure.

DESIGN

Retrospective analysis of paracetamol-associated paediatric acute liver failure cases presenting 2002-2012.

SETTING

New Zealand and Queensland Paediatric Liver Transplant Services.

RESULTS

14 of 54 cases of paediatric acute liver failure were attributed to paracetamol, the majority were secondary to medication errors. 12 of the 14 children were under the age of 5 years. Seven children received doses in excess of 120 mg/kg/day. Many of the other children received either a double dose, too frequent administration, coadministration of other medicines containing paracetamol or regular paracetamol for up to 24 days. Three children underwent transplant. One of these and one other child died.

CONCLUSIONS

In Australia and New Zealand, paracetamol overdose secondary to medication errors is the leading cause of paediatric acute liver failure. A review of regional safety practices surrounding paracetamol use in children is indicated.

N-acetyl cysteine in the management of rodenticide consumption - life saving?

BACKGROUND AND AIM OF STUDY

Rodenticide is a commonly ingested poison in India. Many rodenticides contain hepatotoxic agents and can cause acute liver failure (ALF). There is no antidote for rodenticide poison, and consumption is often fatal. The Role of N acetyl cysteine (NAC) in acetaminophen induced ALF is well established. Additionally some studies have shown that it may be useful in non-acetaminophen induced ALF also. Cases with ALF secondary to suicidal rodenticide consumption have been reported, and some reports show that NAC is beneficial in these cases. Our study was a retrospective analysis of patients admitted with rodenticide consumption, comparing outcomes in those receiving standard of care management and those who were treated with NAC also.

MATERIALS AND METHODS

Case sheets of all inpatients of a tertiary medical college hospital between January 2010 and December 2012 admitted with an alleged history of rodenticide consumption were surveyed and data was extracted and analysed.

STATISTICAL ANALYSIS

Patients were analysed with respect to age, sex, mode of presentation, interval between consumption of rodenticide and starting NAC; the outcome in patients treated with acetylcysteine was compared to outcomes in those not treated with acetylcysteine

RESULTS

A total of 100 patients were studied out of which 18 died. Sixteen of the deaths were in patients who had not been treated with NAC. We found that patients who had received NAC had lower mortality, lower peak values of AST/ALT, and shorter hospital stay.

CONCLUSION

NAC may have a role in the management of ALF associated with rodenticide consumption.

N-acetylcysteine attenuates reactive-oxygen-species-mediated endoplasmic reticulum stress during liver ischemia-reperfusion injury

AIM: To investigate the effects of N-acetylcysteine (NAC) on endoplasmic reticulum (ER) stress and tissue injury during liver ischemia reperfusion injury (IRI).

METHODS: Mice were injected with NAC (300 mg/kg) intraperitoneally 2 h before ischemia. Real-time polymerase chain reaction and western blotting determined ER stress molecules (GRP78, ATF4 and CHOP). To analyze the role of NAC in reactive oxygen species (ROS)-mediated ER stress and apoptosis, lactate dehydrogenase (LDH) was examined in cultured hepatocytes treated by H₂O₂ or thapsigargin (TG).

RESULTS: NAC treatment significantly reduced the level of ROS and attenuated ROS-induced liver injury after IRI, based on glutathione, malondialdehyde, serum alanine aminotransferase levels, and histopathology. ROS-mediated ER stress was significantly inhibited in NAC-treated mice. In addition, NAC treatment significantly reduced caspase-3 activity and apoptosis after reperfusion, which correlated with the protein expression of Bcl-2 and Bcl-xl. Similarly, NAC treatment significantly inhibited LDH release from hepatocytes treated by H₂O₂ or TG.

CONCLUSION: This study provides new evidence for the protective effects of NAC treatment on hepatocytes during IRI. Through inhibition of ROS-mediated ER stress, NAC may be critical to inhibit the ER-stress-related apoptosis pathway.

Intensive care unit management of patients with liver failure

Acute liver failure (ALF) and acute-on-chronic liver failure (ACLF) usually mandate management within an intensive care unit (ICU). Even though the conditions bear some similarities, precipitating causes, and systemic complications management practices differ. Although early identification of ALF and ACLF, improvements in ICU management, and the widespread availability of liver transplantation have improved mortality, optimal management practices have not been defined. This article summarizes current ICU management practices and identifies areas of management that require further study.

Analysis of viral testing in nonacetaminophen pediatric acute liver failure

OBJECTIVE

Viral infections are often suspected to cause pediatric acute liver failure (PALF), but large-scale studies have not been performed. We analyzed the results of viral testing among nonacetaminophen PALF study participants.

METHODS

Participants were enrolled in the PALF registry. Diagnostic evaluation and final diagnosis were determined by the site investigator and methods for viral testing by local standard of care. Viruses were classified as either causative viruses (CVs) or associated viruses (AVs). Supplemental testing for CV was performed if not done clinically and serum was available. Final diagnoses included "viral," "indeterminate," and "other."

RESULTS

Of 860 participants, 820 had at least 1 test result for a CV or AV. A positive viral test was found in 166/820 (20.2%) participants and distributed among "viral" (66/80 [82.5%]), "indeterminate" (52/420 [12.4%]), and "other" (48/320 [15.0%]) diagnoses. CVs accounted for 81/166 (48.8%) positive tests. Herpes simplex virus (HSV) was positive in 39/335 (11.6%) who were tested 26/103 (25.2%) and 13/232 (5.6%) among infants 0 to 6 and >6 months, respectively. HSV was not tested in 61.0% and 53% of the overall cohort and those 0 to 6 months, respectively. Supplemental testing yielded 17 positive, including 5 HSV.

CONCLUSIONS

Viral testing in PALF occurs frequently but is often incomplete. The evidence for acute viral infection was found in 20.2% of those tested for viruses. HSV is an important viral cause for PALF in all age groups. The etiopathogenic role of CV and AV in PALF requires further investigation.

Cell death and cell death responses in liver disease: mechanisms and clinical relevance

Hepatocellular death is present in almost all types of human liver disease and is used as a sensitive parameter for the detection of acute and chronic liver disease of viral, toxic, metabolic, or autoimmune origin. Clinical data and animal models suggest that hepatocyte death is the key trigger of liver disease progression, manifested by the subsequent development of inflammation, fibrosis, cirrhosis, and hepatocellular carcinoma. Modes of hepatocellular death differ substantially between liver diseases. Different modes of cell death such as apoptosis, necrosis, and necroptosis trigger specific cell death responses and promote progression of liver disease through distinct mechanisms. In this review, we first discuss molecular mechanisms by which different modes of cell death, damage-associated molecular patterns, and specific cell death responses contribute to the development of liver disease. We then review the clinical relevance of cell death, focusing on biomarkers; the contribution of cell death to drug-induced, viral, and fatty liver disease and liver cancer; and evidence for cell death pathways as therapeutic targets.

Amelioration of bromobenzene hepatotoxicity by Withania somnifera pretreatment: Role of mitochondrial oxidative stress

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Administration of bromobenzene to rats caused increased levels of liver marker enzymes, lipid peroxidation, TNF-α, IL-1β, VEGF, depletion in levels of mitochondrial enzymes and antioxidants.

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Pre-treatment with Withania somnifera normalized the levels of liver marker enzymes, TNF-α, IL-1β, VEGF, mitochondrial enzymes, antioxidants and ameliorated histopathological manifestations in bromobenzene-treated rats.

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Molecular dockings studies showed strong interactions between pro-inflammatory mediator NF-ƙB and various active components of W. somnifera (Withaferin A, Withanolide D and Withanolide E), thus blocking it from causing progressive tissue damage.

The present study investigated the possible protective role of Withania somnifera (Linn.) Dunal (Solanaceae) root powder against bromobenzene-induced oxidative damage in rat liver mitochondria. Administration of bromobenzene (10 mmol/kg body weight) to rats resulted in increased levels of liver marker enzymes, lipid peroxidation, TNF-α, IL-1β and VEGF. There was also marked depletion in the levels of mitochondrial enzymes and antioxidant activity. Pre-treatment with W. somnifera significantly decreased the levels of liver marker enzymes, TNF-α, IL-1β, VEGF and ameliorated histopathological manifestations in bromobenzene-treated rats. The molecular docking analysis predicted that the pro-inflammatory mediator NF-κB showed significant interaction with selected various active components of W. somnifera (withaferin A, withanolide D and withanolide E). This study demonstrates a good protective effect of W. somnifera against bromobenzene-induced oxidative stress.

Novel protocol including liver biopsy to identify and treat CD8+ T-cell predominant acute hepatitis and liver failure

In the majority of children with ALF, the etiology is unknown and liver transplantation is often needed for survival. A patient case prompted us to consider that immune dysregulation may be the cause of indeterminate acute hepatitis and liver failure in children. Our study includes nine pediatric patients treated under a multidisciplinary clinical protocol to identify and treat immune-mediated acute liver injury. Patients with evidence of inflammation and no active infection on biopsy received treatment with intravenous immune globulin and methylprednisolone. Seven patients had at least one positive immune marker before or after treatment. All patients had a CD8+ T-cell predominant liver injury that completely or partially responded to immune therapy. Five of the nine patients recovered liver function and did not require liver transplantation. Three of these patients subsequently developed bone marrow failure and were treated with either immunosuppression or stem cell transplant. This series highlights the importance of this tissue-based approach to diagnosis and treatment that may improve transplant-free survival. Further research is necessary to better characterize the immune injury and to predict the subset of patients at risk for bone marrow failure who may benefit from earlier and stronger immunosuppressive therapy.