GPT and chronic hepatitis B virus infection: This study analysed the pattern and determinants of ALT elevation in a large cohort of patients with CHD, including young adults, compared to propensity score-matched (PSM) patients with chronic hepatitis B (CHB).<h4>Methods</h4>We identified 2382 treatment-naïve HBsAg+ adults with CHD (HDV RNA positive) and 1553 with CHB attending a liver center in Mongolia during 2015-2023.