Clinical characteristics and treatment outcomes of acute severe autoimmune hepatitis

A Closer Look into Autoimmune Liver Diseases

Autoimmune liver diseases involve a heterogeneous group of chronic inflammatory disorders, including autoimmune hepatitis, primary biliary cholangitis, and primary sclerosing cholangitis. Sometimes presented consistently as an overlapping syndrome, their pathogenesis is rather complex and has yet to be fully elucidated, despite extensive research efforts. This review article corroborates the molecular mechanisms of autoimmune liver diseases, as well as existing and potential therapeutic modalities.

Acute presentation of autoimmune hepatitis -from acute hepatitis to ALF and ACLF

Acute presentation of autoimmune hepatitis (AIH) occurs in 22-43% of all AIH cases, and is not a rare condition. Rather than constituting a single disease entity, it represents a clinical spectrum characterized by considerable variability in severity and the presence of preexisting chronic AIH. This spectrum ranges from acute AIH and acute severe AIH to AIH presenting as acute liver failure (ALF) or as acute-on-chronic liver failure (ACLF), contingent upon factors such as coagulopathy, hepatic encephalopathy, and underlying liver disease. Diagnosing acute presentation of AIH can be particularly challenging due to the frequent absence of classical serologic signatures such as autoantibodies and elevated IgG levels. Histopathological examination remains essential for diagnosis, typically necessitating percutaneous or transjugular liver biopsy. Corticosteroids (CS) are recommended for the management of acute AIH and acute severe AIH with coagulopathy. However, the therapeutic response to CS should be meticulously monitored. If a poor response is anticipated, liver transplantation (LT) should be promptly considered. For AIH presenting as ALF with encephalopathy or ACLF with advanced underlying liver disease, LT is generally advised. Nonetheless, there is potential for a trial of CS therapy in cases of ALF with low MELD scores or ACLF without encephalopathy. This review provides an overview of the latest findings concerning the definition, diagnosis, and management of acute presentation of AIH.

Trends of Costs and Admission Rates Among Patients Admitted With Autoimmune Hepatitis: Analysis of US Hospitals Using the NIS Database

Background and aim

Autoimmune hepatitis (AIH) is a prominent cause of chronic liver disease in the United States. This study aims to characterize the incidence, mortality, and cost implications of this condition using a national database.

Method

The 2016-2019 National Inpatient Sample was used to select patients with AIH. After adjusting for inflation, weighted charge data were used to calculate the admission costs using charge-to-cost ratios. Demographic, socioeconomic status, and comorbidity values were used to build strata to characterize admission incidence, mortality data and aggregate and per-capita cost values. Furthermore, additional sensitivity analysis was performed using a stratified set of patients with AIH as one of the top 10 diagnosis (AIH-specific subsample). Multinomial regression curves were graphed and assessed to derive goodness-of-fit for each trend. R2 and P-values were calculated.

Results

From 2016 to 2019, the total admissions related to AIH were approximately 20,984, 21,905, 22,055, and 22,680 cases, respectively (R2: 0.93, P-value: 0.03). AIH-related hospitalization aggregate costs came to $338.18, $369.17, $355.98, and $387.25 million dollars (R2: 0.75, P-value: 0.17). Significant admission growth was seen in the Southern region (R2: 0.91, P-value: 0.05). Most notably, increasing trends in total admissions were found across older age, those of White and Hispanic descent, and those with comorbidities. On the other hand, the AIH-specific subsample illustrated decreasing trends in admissions across demographics (i.e., age, gender, and race) and comorbidities; however, those with hepatic complications saw a rise in the admission trends (cirrhosis - R2: 0.98, P-value: 0.009; multiple liver complications - R2: 0.95, P-value: 0.03).

Conclusion

Among AIH-specific admissions, there was a decreasing trend overall; however, there was an exceptional increase in the admissions among those with hepatic complications.

Acute Liver Failure Guidelines

Acute liver failure (ALF) is a rare, acute, potentially reversible condition resulting in severe liver impairment and rapid clinical deterioration in patients without preexisting liver disease. Due to the rarity of this condition, published studies are limited by the use of retrospective or prospective cohorts and lack of randomized controlled trials. Current guidelines represent the suggested approach to the identification, treatment, and management of ALF and represent the official practice recommendations of the American College of Gastroenterology. The scientific evidence was reviewed using the Grading of Recommendations, Assessment, Development and Evaluation process to develop recommendations. When no robust evidence was available, expert opinions were summarized using Key Concepts. Considering the variety of clinical presentations of ALF, individualization of care should be applied in specific clinical scenarios.

Detection of Novel Biomarkers in Pediatric Autoimmune Hepatitis by Proteomic Profiling

Autoimmune hepatitis (AIH) is characterized by immune-mediated hepatocyte injury resulting in the destruction of liver cells, causing inflammation, liver failure, and fibrosis. Pediatric (AIH) is an autoimmune inflammatory disease that usually requires immunosuppression for an extended period. Frequent relapses after treatment discontinuation demonstrate that current therapies do not control intrahepatic immune processes. This study describes targeted proteomic profiling data in patients with AIH and controls. A total of 92 inflammatory and 92 cardiometabolic plasma markers were assessed for (i) pediatric AIH versus controls, (ii) AIH type 1 versus type 2, (iii) AIH and AIH-autoimmune sclerosing cholangitis overlapping syndrome and (iv) correlations with circulating vitamin D levels in AIH. A total of 16 proteins showed a nominally significant differential abundance in pediatric patients with AIH compared to controls. No clustering of AIH subphenotypes based on all protein data was observed, and no significant correlation of vitamin D levels was observed for the identified proteins. The proteins that showed variable expression include CA1, CA3, GAS6, FCGR2A, 4E-BP1 and CCL19, which may serve as potential biomarkers for patients with AIH. CX3CL1, CXCL10, CCL23, CSF1 and CCL19 showed homology to one another and may be coexpressed in AIH. CXCL10 seems to be the central intermediary link for the listed proteins. These proteins were involved in relevant mechanistic pathways for liver diseases and immune processes in AIH pathogenesis. This is the first report on the proteomic profile of pediatric AIH. The identified markers could potentially lead to new diagnostic and therapeutic tools. Nevertheless, considering the complex pathogenesis of AIH, more extensive studies are warranted to replicate and validate the present study's findings.

Acute Severe Seronegative Autoimmune Hepatitis With Undiagnosed Graves’ Disease

Autoimmune hepatitis (AIH) is a progressive inflammatory condition hypothesized to be a T-lymphocyte (T-cell)-mediated immune response that commonly affects females more than males. Given its proposed mechanism associated with immune response, it is more likely to present with other autoimmune conditions, particularly autoimmune disorders associated with the thyroid. AIH can be difficult to diagnose as it is a diagnosis of exclusion. AIH lacks validated algorithms for proper diagnosis and can seldom present with negative antibodies. If not fully worked up, AIH may progress to cirrhosis and even increase the risk of malignancy. Therefore, a liver biopsy is a crucial step in the workup for AIH. We report a rare case of acute severe AIH associated with negative antibodies and undiagnosed Graves’ disease.

Glucocorticoid Treatment Strategies in Liver Failure

Liver failure is characterized by serious liver decompensation and high mortality. The activation of systemic immune responses and systemic inflammation are widely accepted as the core pathogenesis of liver failure. Glucocorticoids (GCs) are most regularly utilized to suppress excessive inflammatory reactions and immunological responses. GCs have been used in the clinical treatment of liver failure for nearly 60 years. While there has been no unanimity on the feasibility and application of GC treatment in liver failure until recently. The most recent trials have produced conflicting results when it comes to the dose and time for GC therapy of different etiology of liver failure. Our review outlines the issues and options in managing GC treatment in liver failure based on an investigation of the molecular mechanism that GC may give in the treatment.

Pathogenesis of Autoimmune Hepatitis-Cellular and Molecular Mechanisms

Pediatric autoimmune liver disorders include autoimmune hepatitis (AIH), autoimmune sclerosing cholangitis (ASC), and de novo AIH after liver transplantation. AIH is an idiopathic disease characterized by immune-mediated hepatocyte injury associated with the destruction of liver cells, causing inflammation, liver failure, and fibrosis, typically associated with autoantibodies. The etiology of AIH is not entirely unraveled, but evidence supports an intricate interaction among genetic variants, environmental factors, and epigenetic modifications. The pathogenesis of AIH comprises the interaction between specific genetic traits and molecular mimicry for disease development, impaired immunoregulatory mechanisms, including CD4+ T cell population and Treg cells, alongside other contributory roles played by CD8+ cytotoxicity and autoantibody production by B cells. These findings delineate an intricate pathway that includes gene to gene and gene to environment interactions with various drugs, viral infections, and the complex microbiome. Epigenetics emphasizes gene expression through hereditary and reversible modifications of the chromatin architecture without interfering with the DNA sequence. These alterations comprise DNA methylation, histone transformations, and non-coding small (miRNA) and long (lncRNA) RNA transcriptions. The current first-line therapy comprises prednisolone plus azathioprine to induce clinical and biochemical remission. Further understanding of the cellular and molecular mechanisms encountered in AIH may depict their impact on clinical aspects, detect biomarkers, and guide toward novel, effective, and better-targeted therapies with fewer side effects.