Abstract: Objective To compare the clinical features of patients with autoimmune hepatitis (AIH) presenting with acute versus chronic liver injury, and to evaluate the differences in clinical treatment strategies. Methods Ninety-eight patients with AIH admitted to our hospital betwee January 2020 and January 2022 were selected and divided into two groups based on clinical diagnosis: the acute onset group(n=46) and the chronic onset group (n=52). The clinical data of both groups were analyzed, and the efficacy of glucocorticoid treatment was compared between the two groups. Results Upon analysis, jaundice was more commonly observed as an initial symptom in the acute onset group (21.7%) compared to the chronic onset group (7.7%) (P<0.05). Conversely, the percentage of initially asymptomatic patients was higher in the chronic onset group (28.8%) than in the acute onset group(10.9%) (P<0.05). Regarding inflammatory manifestations, hepatic lobular inflammation was more prevalent in the acute onset group (56.5%) than in the chronic onset group (34.6%) (P<0.05), while portal phlebitis was less common in the acute onset group (17.4%)compared to the chronic onset group (55.8%) (P<0.05).The incidence of fibrosis was higher in the chronic onset group (82.7%) than in the acute onset group(65.2%) (P<0.05). Biochemically, the AST level in the chronic onset group was (169.9±10.4) U/L, lower than in the acute onset group [(206.5±13.5) U/L, P<0.05], the ALT level in the chronic onset group was (196.7±11.4) U/L, also lower than in the acute onset group [(279.8±14.7) U/L, P<0.05]. The IgG level in the chronic onset group was (1807.8±122.7)mg/dl, higher than in the acute onset group [(1648.8±110.9) U/L, P<0.05]. After 6 months of treatment, the ALT level in the acute onset group was (20.1±2.0) U/L, lower than in the chronic onset group [(24.7±1.9) U/L, P<0.05], and the IgG level was (941.5±90.1)mg/dl, lower than in the chronic onset group [(1122.7±100.2)mg/dl, P<0.05]. Conclusion Different inflammatory conditions lead to varing degrees of urgency in onset, resulting in differences in initial symptoms and biochemical indicators. Patients with acute onset respond more significantly to standard treatment regimens compared to those with chronic onset. Therefore, timely adjustments to medication are necessary in clinical treatment, taking into account the type of inflammation and the patient's suitability for the treatment regimen.

Key words: Autoimmune hepatitis, Clinical Features, Interface Hepatitis, Lobular inflammation of the liver, Portal phlebitis