Autoimmune hepatitis (AIH) is a chronic non-resolving liver disease characterized by diffuse hypergammaglobulinemia, the presence of autoantibodies and characteristic histological findings. The disease can have catastrophic outcome with the development of end-stage liver disease if misdiagnosed/undiagnosed and left untreated. AIH pathogenesis remains obscure and the main hypothesis supports its development in genetically predisposed individuals after being exposed to certain environmental triggers. Genetic predisposition is linked to the presence of certain HLA alleles, mainly HLA-DR3 and HLA-DR4. However, a wide number of non-HLA epitopes have also been associated with the disease although data vary significantly among different ethnic groups. Therefore, it is likely that epigenetic alterations may also play a crucial role in disease's pathogenesis, although not yet extensively studied. The aim of this review was to summarize the genetic and environmental factors that have been associated with AIH, but also to open new insights towards the role of epigenetic modifications in the etiology of the disease.

Sjögren’s syndrome (SjS) and primary biliary cholangitis (PBC) can be classified as a model of generalized autoimmune epithelitis based on their frequent coexistence in clinical practice and the highly specific immune mediated injury of target epithelial cells. Both of these autoimmune diseases are characterized by female predominance, highly specific circulating autoantibodies, and immune-mediated destruction of the salivary and lachrymal glands and the biliary epithelial cells, respectively. Although the genetic predisposition has been well described for both diseases, genetic studies have failed to completely elucidate their pathogenesis. The recent integration of epigenetic data, analyzing the different cellular partners, opens new perspectives and allows for better understanding of these complex and still incurable diseases. Epigenetic studies on SjS have elucidated the role of DNA methylation alterations in disease pathogenesis, while epigenetic changes that influence expression of genes on the X chromosome have been implicated in the geo-variability and occurrence of PBC. The aim of this review is to describe the advances in epigenetics in the field of autoimmune epithelitis as well as to highlight how epigenetic changes could contribute to better understanding of disease pathogenesis and progression. These advances could yield insights on novel therapeutic interventions.

FibroMeter and FibroMeter vibration-controlled transient elastography (FibroMeter VCTE) were assessed in a Greek cohort of patients with chronic viral hepatitis (CVH) B and C or metabolic dysfunction-associated steatotic liver disease (MASLD) to evaluate their accuracy in predicting advanced liver fibrosis against other well-validated noninvasive markers. Group 1: n=83 CVH and group 2: n=38 MASLD patients underwent liver biopsy and transient elastography (TE) on the same day as sera collection. FibroMeter scores APRI and FIB-4 were calculated in all 121 patients, while MASLD fibrosis score (MFS) was also calculated in group 2. In CVH, FibroMeter VCTE performed equivalently to TE and better than the other markers in predicting advanced (≥F3) and significant (≥F2) fibrosis (area under the receiver operating characteristic curve [AUC] 0.887, P<0.001 for F3; AUC 0.766 P0.2154 had the same sensitivity (100%) and specificity (81%) as TE (cutoff >7.1 kPa). FibroMeter MASLD >0.25 performed equivalently to MFS and FIB4, but with higher specificity (100%). Both FibroMeter and FibroMeter VCTE correlated with liver histology but not with liver enzymes. FibroMeter VCTE predicts accurately advanced fibrosis in CVH and MASLD, irrespectively of transaminase levels. FibroMeter Virus can be applied only as an alternative marker in CVH, while FibroMeter MASLD performs equally to TE and calculated scores (MFS, FIB-4) in predicting advanced fibrosis in MASLD patients.