A Report on a Nationwide Surveillance System for Pediatric Acute Hepatitis of Unknown Etiology in Korea.

BACKGROUND: Several cases of pediatric acute hepatitis of unknown etiology related to adenoviral infections have been reported in Europe since January 2022. The aim of this study was to compare the incidence, severity, possible etiology, and prognosis of the disease with those in the past in Korea. METHODS: The surveillance group collected data between May and November 2022 using a surveillance system. Acute hepatitis of unknown etiology was defined in patients aged < 16 years with a serum transaminase level > 500 IU/L, not due to hepatitis A-E or other underlying causes. For comparison, data from 18 university hospitals were retrospectively collected as a control group between January 2021 and April 2022. RESULTS: We enrolled 270 patients (mean age, 5 years). The most common symptom was fever. However, the incidence was similar between 2021 and 2022. Liver function test results, number of patients with acute liver failure (ALF), liver transplantation (LT), death, and adenovirus detection rates did not differ between the two groups. None of the adenovirus-positive patients in either group experienced ALF, LT, or death. In the surveillance group, adenovirus-associated virus-2 was detected in four patients, one of whom underwent LT. Patients with an unknown etiology showed significantly higher bilirubin levels, a lower platelet count, and a higher LT rate than patients with a possible etiology. CONCLUSION: The incidence of pediatric acute hepatitis of unknown etiology and adenovirus detection rate have not increased in Korea.

The burden of HEV-related acute liver failure in Bangladesh, China and India: a systematic review and meta-analysis.

BACKGROUND: Hepatitis E can potentially progress to HEV-related acute liver failure (HEV-ALF). East and South Asia bear a substantial burden of HEV infection, with Bangladesh, China, and India facing the most severe threat in this region. Therefore, we conducted a systematic review and meta-analysis to evaluate the burden of HEV-ALF in these three high-risk countries. METHODS: A systematic literature search was performed utilizing PubMed, the Cochrane Library, Medline, Embase, and Web of Science databases. Studies in English or Chinese that reported data on the burden of HEV-ALF in Bangladesh, China and India were included. Outcomes were pooled with meta-analysis utilizing R software. Estimates were calculated with random-effects models, and subgroup analysis and sensitivity analysis were conducted to address heterogeneity. Egger's test and Begg's test were performed to assess publication bias. RESULTS: A total of 20 eligible studies were included in this study. The pooled HEV-attributable proportion of viral-related acute liver failure was estimated to be 40.0% (95% CI: 0.28-0.52), 30.0% (95% CI: 0.18-0.44), and 61.0% (95% CI: 0.49-0.72) among non-pregnant individuals in India, China and Bangladesh, while in Indian pregnant females, it was 71.0% (95% CI: 0.62-0.79). The combined prevalence among non-pregnant HEV-infected participants was 28.0% (95% CI: 0.20-0.37) and 10.0% (95% CI: 0.01-0.28) in India and China, and it was 34.0% (95% CI: 0.27-0.42) in Indian pregnant females with HEV infection. The overall mortality of HEV-ALF was estimated to be 32.0% (95% CI: 0.23-0.42) and 64.0% (95% CI: 0.50-0.77) among the non-pregnant and the pregnant participants in India, and it was 23.0% (95% CI: 0.14-0.34) in Chinese non-pregnant participants. CONCLUSIONS: The burden of HEV-ALF in Bangladesh, China, and India is non-negligible despite geographic and population heterogeneity. The prevention of HEV infection and early recognition of HEV-ALF are of great significance, especially in high-risk countries and populations. REGISTRATION: PROSPERO registration ID is CRD42022382101.

Acute liver failure in low-income and middle-income countries.

Acute liver failure is a rare condition involving the rapid development, progression, and worsening of liver dysfunction, characterised by coagulopathy and encephalopathy, and has a high mortality unless liver transplantation is performed. Population-based studies are scarce, and most published data are from high-income countries, where the main cause of acute liver failure is paracetamol overdose. This Review provides an overview of the scanty literature on acute liver failure in low-income and middle-income countries, where patients are often admitted to primary care hospitals and viral hepatitis (especially hepatitis E), tropical infections (eg, dengue), traditional medicines, and drugs (especially anti-tuberculosis drugs) have an important role. We discuss incidence, cause, occurrence in children and pregnant women, prognostic factors and scores, treatment, and mortality. To conclude, we advocate for international collaboration, the establishment of central registries for the condition, and better diagnostics.

Severe acute hepatitis of unknown etiology in a large cohort of children.

BACKGROUND: We evaluated the proportion, clinical features, and outcomes of previously healthy children presenting to a large Canadian quaternary pediatric center with severe acute hepatitis of unknown etiology. METHODS: All patients with serum alanine aminotransferase (ALT) > 500 U/L or aspartate aminotransferase (AST) > 500 U/L between June 1, 2018, and May 31, 2022, at The Hospital for Sick Children, were identified. Subjects with only AST > 500 U/L were excluded. Clinical characteristics, investigations, and outcomes for patients without clear etiology for ALT > 500 U/L (severe acute hepatitis of unknown etiology) for our study period and from October 1 to May 31 of each year 2018-2021 were reviewed. RESULTS: Of 977 patients with ALT/AST> 500 U/L, 720 had only ALT > 500 U/L. We excluded age below 6 months (n = 99) or above 16 years (n = 66), known pre-existing liver conditions (n = 66), and ALT > 500 U/L in already admitted patients (n = 151). Among the remaining 338 children with ALT > 500 U/L at presentation, an etiology was identified in 303 subjects. 33 (9.8%) children [median age 6.1 y (range 0.5-15.5); 61% male] were confirmed as severe acute hepatitis of unknown etiology. Twenty patients (60.6%) were tested for blood adenovirus by PCR, and 1 (5%) was positive (serotype B7). Liver tissue specimens from 18 patients revealed no evidence of viral inclusions or adenovirus. Twelve (36.3%) presented with pediatric acute liver failure, with 8 (24.2%) requiring liver transplantation. There were no deaths. Hepatitis-associated aplastic anemia occurred in 5 (15%) patients. CONCLUSIONS: Of children presenting with severe acute hepatitis to a quaternary children's hospital over a 48-month period, 9.8% had unknown etiology with no change over time. Liver transplantation remains an important treatment strategy for those presenting with pediatric acute liver failure phenotype. The frequency of cases associated with human adenovirus infection was noncontributory.

Prevalence, Risk Factors, and Impact of Bacterial or Fungal Infections in Acute Liver Failure Patients from India.

BACKGROUND: We evaluated the prevalence, risk factors, and impact of bacterial/fungal infections in acute liver failure (ALF) patients. METHODS: We analyzed clinical, biochemical, and microbiological data of ALF patients with and without bacterial/fungal infections admitted at an institute over the last 5 years. RESULTS: We enrolled 143 patients, 50% males, median age 25 years, with acute viral hepatitis (32.2%), drug-induced injury (18.2%), and tropical illness (14%) as aetiologies of ALF. 110 patients (76.9%) developed bacterial/fungal infections [Bacterial infection: MDR: 70%, PDR: 7%, ESBL: 40%, CRE: 30%, CRAB: 26.6%, MDR-EF: 13.3% and fungal infection: 19 (17.3%)]. On univariable analysis, SIRS (33.6% vs.3%), ICU admission (78.2% vs. 45.5%), mechanical ventilation (88.2% vs. 51.5%), inotropes (39.1% vs. 6.1%), invasive catheters (91.8% vs. 39.4%), and prolonged catheterization (6 days vs. 0 days) were significant risk factors for infections (p < 0.05, each). In contrast, SIRS and catheterization independently predicted infection on multivariable regression. Organ failures [3 (2-4) vs. 1 (0-2)], grade-III-IV HE (67.3% vs. 33.3%), circulatory failure (39.1% vs. 6.1%), coagulopathy (INR > 2.5: 58.2% vs. 33.3%), renal injury (28.2% vs. 6.1%) (p < 0.05), MELD (32.9 ± 8.2 vs. 26.7 ± 8.3) and CPIS [3(2-4) vs. 2(0-2)] were higher in infected vs. non-infected patients (p < 0.001). 30-day survival was significantly lower in infected vs. non-infected patients (17.3% vs. 75.8%, p < 0.001), while no patient survived with fungal infections. Refractory septic shock was the commonest cause of mortality in patients. CONCLUSIONS: Infections due to MDR organisms are high, fungal infections are fatal, and refractory septic shock is the dominant reason for mortality, implying bacterial and fungal infections as the major killer in ALF patients.

Acute liver failure secondary to the use of unmonitored drugs and herbal supplements: an underreported and serious issue.

Acute liver failure (ALF) is a potentially fatal illness marked by the abrupt development of jaundice, coagulopathy, and hepatic encephalopathy (HE) in persons having no previous history of hepatic disease. It is a relatively uncommon illness, having an incidence of 1 to 8 per million people. Hepatitis A, B, and E viruses have been documented as the most prevalent etiologies of acute liver failure in Pakistan and other developing nations. However, ALF may also occur secondary to toxicity caused by the unmonitored overdosing and toxicity of traditional medicines, herbal supplements, and alcohol. Similarly, in some instances, the etiology remains unknown. Herbal products, alternative, and complementary therapies are frequently practiced across the globe for treating various illnesses. In recent times, their use has gained much popularity. Indications and the use of these supplementary drugs vary significantly. The majority of these products have not gained approval from Food and Drug Administration (FDA). Unfortunately, the incidence of documented adverse effects linked to the usage of herbal products has increased recently, but still, these events are underreported, and the condition is known as drug-induced liver injury (DILI) and herb-induced liver injury (HILI). The estimated total herbal retail sales increased from $4230 million in 2000 to $6032 million in 2013, representing a total of 42 and 3.3% per annum increase. To reduce the occurrence of HILI and DILI, physicians in general practice settings should inquire about patients' understanding of potential toxicity with the consumption of hepatotoxic and herbal medicines.

Etiology and Outcome of Adult and Pediatric Acute Liver Failure in Europe.

Acute liver failure (ALF) is rare but life-threatening. Common causes include intoxications, infections, and metabolic disorders. Indeterminate etiology is still frequent. No systematic data on incidence, causes, and outcome of ALF across Europe are available. Via an online survey we reached out to European Reference Network Centers on rare liver diseases. Numbers and etiology of ALF cases during 2020 were retrieved and diagnostic and treatment availabilities assessed. In total, 455 cases (306 adult, 149 pediatric) were reported from 36 centers from 20 countries. Intoxication was the most common cause in adult and pediatric care. The number of cases with indeterminate etiology is low. Diagnostic tools and specific treatment options are broadly available within this network. This is the first approach to report on etiology and outcome of ALF in the pediatric and adult population in Europe. High diagnostic yield and standard of care reflects the expert status of involved centers.

High yield on aetiology using a systematic diagnostic approach to paediatric acute liver failure, analysis of a nationwide cohort.

AIM: Paediatric acute liver failure (P-ALF) is a rare and devastating condition that leads to death or liver transplantation (LTx) in 40%-60% of cases. Determining the aetiology can enable disease-specific treatment, aid in prognostication for hepatic recovery and guide the decision-making for liver transplantation. This study aimed to retrospectively evaluate a systematic diagnostic approach to P-ALF in Denmark and to collect epidemiological nationwide data. METHODS: All Danish children aged 0-16 years with P-ALF diagnosed between 2005 and 2018, and who were evaluated using a standardised diagnostic assessment programme, were eligible for retrospective analysis of clinical data. RESULTS: A total of 102 children with P-ALF were included (presentation at 0 days to 16.6 years of age, 57 females). Aetiological diagnosis was established in 82% of cases, the remainder were indeterminate. Fifty percent of children with P-ALF of indeterminate aetiology died or underwent LTx within 6 months after their P-ALF diagnosis, compared to 24% of children with an aetiological diagnosis, p = 0.04. CONCLUSION: Following a systematic diagnostic evaluation programme, made it possible to identify the aetiology of P-ALF in 82% of cases which is associated with improved outcomes. The diagnostic workup should never be considered complete but rather adapt to ongoing diagnostic advances.

Association of FDA Mandate Limiting Acetaminophen (Paracetamol) in Prescription Combination Opioid Products and Subsequent Hospitalizations and Acute Liver Failure.

Importance: In January 2011, the US Food and Drug Administration (FDA) announced a mandate to limit acetaminophen (paracetamol) to 325 mg/tablet in combination acetaminophen and opioid medications, with manufacturer compliance required by March 2014. Objective: To assess the odds of hospitalization and the proportion of acute liver failure (ALF) cases with acetaminophen and opioid toxicity prior to and after the mandate. Design, Setting, and Participants: This interrupted time-series analysis used hospitalization data from 2007-2019 involving ICD-9/ICD-10 codes consistent with both acetaminophen and opioid toxicity from the National Inpatient Sample (NIS), a large US hospitalization database, and ALF cases from 1998-2019 involving acetaminophen and opioid products from the Acute Liver Failure Study Group (ALFSG), a cohort of 32 US medical centers. For comparison, hospitalizations and ALF cases consistent with acetaminophen toxicity alone were extracted from the NIS and ALFSG. Exposures: Time prior to and after the FDA mandate limiting acetaminophen to 325 mg in combination acetaminophen and opioid products. Main Outcomes and Measures: Odds of hospitalization involving acetaminophen and opioid toxicity and percentage of ALF cases from acetaminophen and opioid products prior to and after the mandate. Results: In the NIS, among 474 047 585 hospitalizations from Q1 2007 through Q4 2019, there were 39 606 hospitalizations involving acetaminophen and opioid toxicity; 66.8% of cases were among women; median age, 42.2 (IQR, 28.4-54.1). In the ALFSG, from Q1 1998 through Q3 2019, there were a total of 2631 ALF cases, of which 465 involved acetaminophen and opioid toxicity; 85.4% women; median age, 39.0 (IQR, 32.0-47.0). The predicted incidence of hospitalizations 1 day prior to the FDA announcement was 12.2 cases/100 000 hospitalizations (95% CI, 11.0-13.4); by Q4 2019, it was 4.4/100 000 hospitalizations (95% CI, 4.1-4.7) (absolute difference, 7.8/100 000 [95% CI, 6.6-9.0]; P < .001). The odds of hospitalizations with acetaminophen and opioid toxicity increased 11%/y prior to the announcement (odds ratio [OR], 1.11 [95% CI, 1.06-1.15]) and decreased 11%/y after the announcement (OR, 0.89 [95% CI, 0.88-0.90]). The predicted percentage of ALF cases involving acetaminophen and opioid toxicity 1 day prior to the FDA announcement was 27.4% (95% CI, 23.3%-31.9%); by Q3 2019, it was 5.3% (95% CI, 3.1%-8.8%) (absolute difference, 21.8% [95% CI, 15.5%-32.4%]; P < .001). The percentage of ALF cases involving acetaminophen and opioid toxicity increased 7% per year prior to the announcement (OR, 1.07 [95% CI, 1.03-1.1]; P < .001) and decreased 16% per year after the announcement (OR, 0.84 [95% CI, 0.77-0.92]; P < .001). Sensitivity analyses confirmed these findings. Conclusions and Relevance: The FDA mandate limiting acetaminophen dosage to 325 mg/tablet in prescription acetaminophen and opioid products was associated with a statistically significant decrease in the yearly rate of hospitalizations and proportion per year of ALF cases involving acetaminophen and opioid toxicity.

Acute Liver Failure in Dengue: A Common but Overlooked Entity in Pediatric Patients in Tropical Countries.

OBJECTIVE: The objective of the study is to estimate the incidence of acute liver failure (ALF) in dengue infection, understand the demographic and biochemical profiles, and identify prognostic factors associated with mortality. METHODOLOGY: This is a retrospective observational study. We evaluated the data of all pediatric dengue patients admitted over the last 5 years in our hospital to identify patients who fulfilled the criteria for pediatric ALF. Demographic profile, and biochemical and radiological parameters were assessed. Their outcomes and mortality data were analyzed to identify prognostic factors. RESULTS: Thirty children with dengue infection were identified to have developed a during the ALF study period which was 29.1% (30 of 103) of all our ALF admissions. A total of 189 children with dengue infection needed admission during the same period and 15.8% (30 of 189) of them developed ALF. The mean duration of onset of ALF was 5.4 days after fever onset. Twenty-two patients (73%) survived, and 8 patients expired. High creatinine, low albumin level, and multisystemic involvement were identified as poor prognostic markers in those patients who did not survive. CONCLUSION: ALF is common in admitted severe dengue patients. A significant proportion of acute liver patients in endemic countries can be attributed to dengue infection. Low serum albumin, high creatinine, and multi-organ dysfunction during acute illness can be used as prognostic markers in these children. Multicentric prospective studies are needed to validate these results.

Changes in Epidemiology of Acetaminophen Overdoses in an Urban County Hospital After 20 Years.

INTRODUCTION: Acetaminophen (APAP) toxicity is the main cause of acute liver failure in the United States. A prior series (1992-1995) identified 71 hospitalized adults with APAP toxicity through the International Statistical Classification of Disease and Related Health Problems, 9th revision (ICD-9) code at Parkland Hospital, Dallas, TX. METHODS: We used a laboratory database search of serum APAP levels from 2011 to 2015 to identify patients with APAP toxicity in the same hospital. RESULTS: We identified 140 patients hospitalized for APAP toxicity from 27,143 APAP levels obtained; 35 required Intensive Care Unit (ICU) admission, and there were no deaths. APAP toxicity/100,000 admissions was similar between eras. DISCUSSION: APAP toxicity continues unabated after 20 years but with improved overall outcomes.

High Prevalence of Hemophagocytic Lymphohistiocytosis in Acute Liver Failure of Infancy.

OBJECTIVES: To investigate the prevalence of hemophagocytic lymphohistiocytosis (HLH) syndrome in pediatric acute liver failure (PALF) of infancy and assess the diagnostic role of rapid immunologic tests, genotype/phenotype correlations, and clinical outcomes. STUDY DESIGN: We retrospectively analyzed 78 children with PALF aged <24 months referred over almost 2 decades. The studied patients with a phenotype of HLH syndrome had a comprehensive immunologic workup, including additional genetic analysis for primary immunologic causes. RESULTS: Thirty of the 78 children had the HLH phenotype and underwent genetic assessment, which demonstrated positive findings in 19 (63.3%), including 9 (30%) with biallelic primary HLH mutations and 10 (33.3%) with heterozygous mutations and/or polymorphisms. The most common form of primary HLH was familial hemophagocytic lymphohistiocytosis (FHL)-2, diagnosed in 6 children, 4 of whom had a c.50delT (p.Leu17ArgfsTer34) mutation in the PRF1 gene. Three patients with primary HLH received genetic diagnoses of FHL-3, Griscelli syndrome, and LRBA (lipopolysaccharide-responsive vesicle trafficking, beach- and anchor-containing) protein deficiency. Overall mortality in the series was 52.6% (10 of 19), and mortality in children with a documented biallelic pathogenic HLH mutation (ie, primary HLH) was 66.6% (6 of 9). Two children underwent liver transplantation, and 4 children underwent emergency hematopoietic stem cell transplantation; all but 1 child survived medium term. CONCLUSIONS: Primary HLH can be diagnosed retrospectively in approximately one-third of infants with indeterminate PALF (iPALF) who meet the clinical criteria for HLH, often leading to their death. The most common HLH type in iPALF is FHL-2, caused by biallelic mutations in PRF-1. The clinical relevance of observed heterozygous mutations and variants of uncertain significance requires further investigation. Prompt hematopoietic stem cell transplantation could be life-saving in infants who survive the liver injury.

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.

Severe acute hepatitis and acute liver failure of unknown origin in children: a questionnaire-based study within 34 paediatric liver centres in 22 European countries and Israel, April 2022.

To detect potential concern about severe acute hepatitis in children, we conducted a survey among 50 ERN RARE-LIVER centres. By 26 April 2022, 34 centres, including 25 transplant centres, reported an estimated median of 3-5, 0-2 and 3-5 cases in 2021, 2020 and 2019 and a mean of 2 (range: 0-8) cases between January and April 2022 (mean in 10 large liver transplant centres: 3). Twelve centres reported suspicion of an increase, but no rise.

Prevalence, severity, duration and resolution of cholestasis after acute liver failure.

OBJECTIVE: Persistent cholestasis may follow acute liver failure (ALF), but its course remains unknown. We aimed to describe the prevalence, onset, severity, duration and resolution of post-ALF cholestasis. DESIGN: Cohort of 127 adult patients with ALF at a liver transplantation centre identified using electronic databases. We obtained laboratory data every 6 hours for the first week, daily until day 30 and weekly, when documented, until day 180. RESULTS: Median age was 40.7 (IQR 31.0-52.4) years, median peak alanine aminotransferase level was 5494 (2521-8819) U/L and 87 (68.5%) cases had paracetamol toxicity. Overall, 12.6% underwent transplantation (3.4% for paracetamol vs 32.5% for non-paracetamol; p<0.001). Ninety-day mortality was 20.7% for paracetamol versus 30.0% for non-paracetamol patients. All non-transplanted survivors reached a bilirubin level>50 µmol/L, which peaked 3.5 (1.0-10.1) days after admission at 169.0 (80.0-302.0) µmol/L. At hospital discharge, 18.8% of patients had normal bilirubin levels and, at a median follow-up time from admission to last measurement of 16 (10-30) days, 46.9% had normal levels. Similarly, there was an increase in alkaline phosphatase (ALP) (207.0 (148.0-292.5) U/L) and gamma-glutamyl transferase (GGT) (336.0 (209.5-554.5) U/L) peaking at 4.5 days, with normalised values in 40.3% and 8.3% at hospital discharge. CONCLUSION: Post-ALF cholestasis is ubiquitous. Bilirubin, ALP and GGT peak at 3 to 5 days and, return to baseline in the minority of patients at median follow-up of 16 days. These data inform clinical expectations of the natural course of this condition.

Secular Trends in Severe Idiosyncratic Drug-Induced Liver Injury in North America: An Update From the Acute Liver Failure Study Group Registry.

INTRODUCTION: Idiosyncratic drug-induced liver injury (DILI) is the second leading cause of acute liver failure (ALF) in the United States. Our study aims were to characterize secular trends in the implicated agents, clinical features, and outcomes of adults with DILI ALF over a 20-year period. METHODS: Among 2,332 patients with ALF enrolled in the ALF Study Group registry, 277 (11.9%) were adjudicated as idiosyncratic DILI ALF (INR ≥ 1.5 and hepatic encephalopathy) through expert opinion. The 155 cases in era 1 (January 20, 1998-January 20, 2008) were compared with the 122 cases in era 2 (January 21, 2008-January 20, 2018). RESULTS: Among 277 cases of DILI ALF, 97 different agents, alone or in combination, were implicated: antimicrobials, n = 118 (43%); herbal/dietary supplements (HDS), n = 42 (15%); central nervous system agents/illicit substances, n = 37 (13%); oncologic/biologic agents, n = 29 (10%); and other, n = 51 (18%). Significant trends over time included (i) an increase in HDS DILI ALF (9.7% vs 22%, P < 0.01) and decrease in antimicrobial-induced DILI ALF (45.8% vs. 38.5%, P = 0.03) and (ii) improved overall transplant-free survival (23.5%-38.7%, P < 0.01) while the number of patients transplanted declined (46.4% vs 33.6%, P < 0.03). DISCUSSION: DILI ALF in North America is evolving, with HDS cases rising and other categories of suspect drugs declining. The reasons for a significant increase in transplant-free survival and reduced need for liver transplantation over time remain unclear but may be due to improvements in critical care, increased NAC utilization, and improved patient prognostication.

Mortality Rates of Severe Dengue Viral Infection Before and After Implementation of a Revised Guideline for Severe Dengue.

OBJECTIVES: To compare the mortality rate of severe dengue (SD) before and after implementation of a revised SD guideline. METHODS: Medical records of SD patients <15 years of age hospitalized during 1998-2020 were reviewed. The revised SD guidelines were implemented in 2016, including intensive monitoring of vital signs and intra-abdominal pressure, the release of intra-abdominal pressure in cases of abdominal compartment syndrome (ACS) and the use of N-acetyl cysteine in cases of acute liver failure. RESULTS: On initial admission, organ failure including severe bleeding, acute respiratory failure, acute kidney injury and acute liver failure was not significantly different between 78 and 23 patients treated in the pre- and postrevised guideline periods, respectively. After hospitalization, the proportions of patients who developed profound shock (68.8% vs. 41.2%), multiorgan failures (60.4% vs. 73.3%), ACS (37.2% vs. 26.1%) and fatal outcome (33.3% vs. 13.0%) were also not significantly different between the pre- and postrevised guideline periods, respectively. In subgroup analysis, the mortality rates in patients with multiorgan failure (44.1% vs. 15.8%), acute respiratory failure and active bleeding (78.1% vs. 37.5%) and ACS (82.8% vs. 33.3%), respectively, were significantly higher in the pre- than the postrevised guideline periods. The durations of time before the liver function tests returned to normal levels, and the mortality rates in acute liver failure patients treated with and without N-acetyl cysteine were not significantly different. CONCLUSIONS: Although following the revised guidelines could not prevent organ failure, the mortality rates in patients with multiorgan failure and/or ACS decreased significantly when following the revised guidelines.