Drug-induced autoimmune-like hepatitis: a diagnostic challenge

Autoimmune Hepatitis: A Diagnostic and Therapeutic Overview

Autoimmune hepatitis is an immune-mediated inflammatory condition of the liver of undetermined cause that affects both sexes, all ages, races, and ethnicities. Its clinical presentation can be very broad, from having an asymptomatic and silent course to presenting as acute hepatitis, cirrhosis, and acute liver failure potentially requiring liver transplantation. The diagnosis is based on histological abnormalities (interface hepatitis), characteristic clinical and laboratory findings (increased aspartate aminotransferase, alanine aminotransferase, and serum IgG concentration), and the presence of one or more characteristic autoantibodies. The large heterogeneity of these clinical, biochemical, and histological findings can sometimes make a timely and proper diagnosis a difficult task. Treatment seeks to achieve remission of the disease and prevent further progression of liver disease. First-line therapy includes high-dose corticosteroids, which are later tapered to decrease side effects, and azathioprine. In the presence of azathioprine intolerance or a poor response to the standard of care, second-line therapy needs to be considered, including mycophenolate mofetil. AIH remains a diagnostic and therapeutic challenge, and a further understanding of the pathophysiological pathways of the disease and the implementation of randomized controlled trials are needed.

Vaccine-Related Autoimmune Hepatitis: Emerging Association with SARS-CoV-2 Vaccination or Coincidence?

BACKGROUND

There is an increasing number of liver injury cases resembling autoimmune hepatitis (AIH) following SARS-CoV-2 vaccination; however, an association has not yet been established.

METHODS/MATERIALS

A literature review was performed to identify articles regarding the association of AIH with vaccination, emphasizing on SARS-CoV-2 vaccines, and the proposed mechanisms. We then performed a literature search for AIH-like cases following SARS-CoV-2 vaccination, and we evaluated the included cases for AIH diagnosis using simplified diagnostic criteria (SDC), and for vaccination causality using the Naranjo score for adverse drug reactions.

RESULTS

We identified 51 AIH-like cases following SARS-CoV-2 vaccination. Forty cases (80%) were characterized as "probable", "at least probable", or "definite" for AIH diagnosis according to SDC. Forty cases (78.4%) were characterized as "probable", four (7.8%) as "possible", and three (5.8%) as "definite" for vaccine-related AIH according to the Naranjo score.

CONCLUSION

SARS-CoV-2 vaccine-related AIH carries several phenotypes and, although most cases resolve, immunosuppressive therapy seems to be necessary. Early diagnosis is mandatory and should be considered in any patient with acute or chronic hepatitis after SARS-CoV-2 vaccination, especially in those with pre-existing liver disease.

Setting up criteria for drug-induced autoimmune-like hepatitis through a systematic analysis of published reports

Nitrofurantoin, minocycline, methyldopa and infliximab, have been found to induce autoimmune-like hepatitis (DI-AILH). Evidence for other drugs and herbal and dietary supplements (HDS) is unclear. The aims of the study were to establish criteria to define and review the published evidence of suspected DI-AILH. Search was undertaken in Pubmed using search terms "drug-induced liver injury," "autoimmune hepatitis," and "drug-induced autoimmune hepatitis." DI-AILH was defined as (1) drug as a potential trigger of liver injury with autoimmune features and histological findings compatible with AIH; (2) no or incomplete recovery or worsening of liver tests after discontinuation of the drug; (3) corticosteroids requirement or spontaneous recovery; (4) follow-up without immunosuppression (IS) and no relapse of AIH at least 6 months after discontinuation of IS; and (5) drugs potentially inducing AILH with a chronic course. Cases fulfilling the first four criteria were considered probable DI-AILH with three possible DI-AILH. A total of 186 case reports were identified for conventional drugs (n = 148; females 79%; latency 2.6 months) and HDS (n = 38; females 50%). The most commonly reported agents of DI-AILH were interferons (n = 37), statins (n = 24), methylprednisolone (MPS) (n = 16), adalimumab (n = 10), imatinib (n = 8), and diclofenac (n = 7). Tinospora cordifolia and Khat were the only HDS with probable DI-AILH cases. No relapses of AIH were observed when IS was stopped after interferons, imatinib, diclofenac, and methylprednisolone. Conclusion: Beyond well-recognized nitrofurantoin, methyldopa, hydralazine, minocycline, and infliximab as causes of DI-AILH, interferons, imatinib, adalimumab, and MPS were the best-documented agents leading to probable DI-AILH. Khat and Tinospora cordifolia were the only HDS found to be able to induce DI-AILH. Long-term immunosuppression appears to be rarely required in patients with DI-AILH due to these drugs.

Chronic liver injury induced by drugs and toxins

Drug-induced liver injury (DILI) occurs in a small fraction of individuals exposed to drugs, herbs or dietary supplements and is a relatively rare diagnosis compared with other liver disorders. DILI can be serious, resulting in hospitalization and even life-threatening liver failure, death or need for liver transplantation. Toxic liver damage usually presents as an acute hepatitis viral-like syndrome or as an acute cholestasis that resolves upon drug discontinuation. However, un-resolving chronic outcome after acute DILI can ensue in some subjects, the mechanisms and risk factors for this particular evolution being yet scarcely known. Furthermore, the definition of chronicity after acute DILI is controversial, regarding both the time frame of liver injury persistence and the magnitude of the abnormalities required. Besides this, in some instances the phenotypes and pathological manifestations are those of chronic liver disease at the time of DILI diagnosis. These include non-alcoholic fatty liver disease, vascular lesions, drug-induced autoimmune hepatitis, chronic cholestasis leading to vanishing bile duct syndrome and even cirrhosis, and some drugs such as amiodarone or methotrexate have been frequently implicated in some of these forms of chronic DILI. In addition, all of these DILI phenotypes can be indistinguishable from those related to other etiologies, making the diagnosis particularly challenging. In this manuscript we have critically reviewed the more recent data on chronicity in DILI with a particular focus on the epidemiology, mechanisms and risk factors of atypical chronic DILI phenotypes.

Potential triggering factors of acute liver failure as a first manifestation of autoimmune hepatitis-a single center experience of 52 adult patients

AIM

To investigate potential triggering factors leading to acute liver failure (ALF) as the initial presentation of autoimmune hepatitis (AIH).

METHODS

A total of 565 patients treated at our Department between 2005 and 2017 for histologically-proven AIH were retrospectively analyzed. However, 52 patients (9.2%) fulfilled the criteria for ALF defined by the "American Association for the Study of the Liver (AASLD)". According to this definition, patients with "acute-on-chronic" or "acute-on-cirrhosis" liver failure were excluded. Following parameters with focus on potential triggering factors were evaluated: Patients' demographics, causation of liver failure, laboratory data (liver enzymes, MELD-score, autoimmune markers, virus serology), liver histology, immunosuppressive regime, and finally, outcome of our patients.

RESULTS

The majority of patients with ALF were female (84.6%) and mean age was 43.6 ± 14.9 years. Interestingly, none of the patients with ALF was positive for anti-liver kidney microsomal antibody (LKM). We could identify potential triggering factors in 26/52 (50.0%) of previously healthy patients presenting ALF as their first manifestation of AIH. These were drug-induced ALF (57.7%), virus-induced ALF (30.8%), and preceding surgery in general anesthesia (11.5%), respectively. Unfortunately, 6 out of 52 patients (11.5%) did not survive ALF and 3 patients (5.7%) underwent liver transplantation (LT). Comparing data of survivors and patients with non-recovery following treatment, MELD-score (P < 0.001), age (P < 0.05), creatinine (P < 0.01), and finally, ALT-values (P < 0.05) reached statistical significance.

CONCLUSION

Drugs, viral infections, and previous surgery may trigger ALF as the initial presentation of AIH. Advanced age and high MELD-score were associated with lethal outcome.

Clinical significance of serum anti-nuclear antibody level in patients with drug-induced liver injury

AIM

To analyze the clinical characteristics of serum anti-nuclear antibody (ANA) in patients with drug-induced liver injury (DILI).

METHODS

This analysis was performed on the clinical data of 44 patients who were admitted to the First Affiliated Hospital of Zhengzhou University from 2012 to 2015 and diagnosed with DILI by liver puncture. The participants were divided into a low-titer ANA group, a high-titer ANA group, and an ANA-negative group. Comparisons were made for laboratory parameters such as alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), gamma-glutamyl transpeptidase (GGT), globulin (GLB), and immunoglobulin G (IgG), age, clinical features and pathological characteristics, and therapeutic effects. Comparisons of normally distributed continuous data between groups were performed by one-way analysis of variance, comparisons of non-normally distributed continuous data between groups were made by rank-sum test, and comparisons of categorical data between groups were performed by chi-square test.

RESULTS

Among the 44 patients, 16 had low-titer ANA, 11 had high-titer ANA, and 17 were negative for ANA. There were no significant differences in ALT, AST, ALP, GGT, age or clinical features between the three groups (P > 0.05). GLB, IgG, pathological characteristics, and therapeutic effects differed significantly between the three groups (P < 0.05).

CONCLUSION

As serum ANA titer increases, liver autoimmune phenomenon becomes prominent in patients with DILI. Liver biopsy pathology is of great significance for the diagnosis and disease evaluation.

Drug-induced autoimmune liver disease: A diagnostic dilemma of an increasingly reported disease

The aetiology of autoimmune hepatitis (AIH) is uncertain but the disease can be triggered in susceptible patients by external factors such as viruses or drugs. AIH usually develops in individuals with a genetic background mainly consisting of some risk alleles of the major histocompatibility complex (HLA). Many drugs have been linked to AIH phenotypes, which sometimes persist after drug discontinuation, suggesting that they awaken latent autoimmunity. At least three clinical scenarios have been proposed that refers to drug- induced autoimmune liver disease (DIAILD): AIH with drug-induced liver injury (DILI); drug induced-AIH (DI-AIH); and immune mediated DILI (IM-DILI). In addition, there are instances showing mixed features of DI-AIH and IM-DILI, as well as DILI cases with positive autoantibodies. Histologically distinguishing DILI from AIH remains a challenge. Even more challenging is the differentiation of AIH from DI-AIH mainly relying in histological features; however, a detailed standardised histologic evaluation of large cohorts of AIH and DI-AIH patients would probably render more subtle features that could be of help in the differential diagnosis between both entities. Growing information on the relationship of drugs and AIH is being available, being drugs like statins and biologic agents more frequently involved in cases of DIAILD. In addition, there is some evidence on the fact that patients diagnosed with DIAILD may have had a previous episode of hepatotoxicity. Further collaborative studies in DIAILD will strengthen the knowledge and understanding of this intriguing and complex disorder which might represent different phenotypes across the spectrum of disease.

A Tale of Unequal Substitution

Objective: In this case report, we describe the development of an acute autoimmune hepatitis associated with a short course of minocycline prescribed for a skin infection. Due to a drug shortage, minocycline was substituted for doxycycline. Conclusions: It is imperative that practitioners be aware of the different risks that accompany switching between drugs in the tetracycline class, particularly the risk of autoimmune conditions including hepatitis.