(A) Schematic timeline of the procedures. C57BL/6J mice were treated with 8-week CCl4 to induce chronic liver injury, followed by additional challenges: Group 1, no additional challenges; Group 2, acute insult (a double dose of CCl4 injection); Group 3, Klebsiella pneumoniae (K.P.) infection; Group 4, acute insult and K.P. infection. (B) Survival rates (n=8). (C) Serum ALT levels. (D) Total bilirubin (TBIL), white blood cells, neutrophil percentage, blood bacterial loads, and BUN were measured 72 hours post-acute CCl4 injection. (E) Representative staining images from the group 4. (F) Hepatic and renal blood flow were determined 72 hours post-acute insult. One-way ANOVA was used for statistical evaluation (*P<0.05, **P<0.01, ***P<0.001, n=4-8 in panels C-E).