Liver and spleen volumes in children with autoimmune hepatitis: association with laboratory parameters and fibrosis stage. A single-center, ambispective, cohort, non-randomized study

Background. Autoimmune hepatitis (AIH) in children is characterized by chronic hepatic inflammation, which may lead to organ enlargement, fibrosis progression, and development of portal hypertension. However, objective assessment of liver and spleen volume changes, and their association with laboratory parameters and fibrosis stage, remains insufficiently studied. Aim. To evaluate liver and spleen volume dynamics in children with AIH and their correlation with laboratory activity and fibrosis stage. Materials and methods. The study included 98 children with a confirmed diagnosis of AIH who were followed for 2 years. 62 of them had isolated AIH and 36 had AIH with overlapping cholangitis. All patients underwent laboratory tests (ALT, AST, GGT, albumin), MRI-based volumetric assessment of liver and spleen, and liver elastography with fibrosis staging according to the Metavir scale. Correlation, comparative and multivariate regression analyses were performed, including dynamic changes in parameters. The study was conducted with follow-up assessments at 1 year and 2 years. Results. Liver enlargement was more frequently observed in children with cholangitis (38.9%), while most patients with isolated AIH had liver volumes within the normal range or reduced. Significant correlations between liver volume, laboratory indicators, and fibrosis stage were found only in the cholangitis group. In children with isolated AIH, a positive dynamic trend was noted, including decreased ALT, AST, GGT levels and reduced liver stiffness on elastography. Spleen volume increase correlated with signs of inflammation and fibrosis but showed no statistically significant change over two years. According to regression analysis, a significant correlation was found between fibroelastography parameters and albumin levels, liver and spleen volumes, ALT and GGT levels, particularly in the group with cholangitis (R2 = 61.4%). Conclusion. Changes in liver and spleen volumes in children with autoimmune hepatitis may be associated with both disease activity and the degree of fibrosis. Patients with AIH combined with cholangitis more frequently exhibit liver enlargement, lower treatment sensitivity, and a lack of reduction in liver stiffness over time. Measuring liver and spleen volumes, along with assessing fibroelastography parameters, allows for a more comprehensive characterization of the clinical course of AIH in children.