Abstract
BACKGROUND: Acute-on-chronic liver failure (ACLF) is a syndrome in patients with cirrhosis with high short-term mortality. Infection is a frequent precipitant of ACLF; however, it is unclear if prognosis varies by difference infectious sources. To address this knowledge gap, we utilized a large national database of patients with cirrhosis. METHODS: This was a retrospective cohort study of patients with cirrhosis in the Veterans Health Administration between 2008 and 2016. First ACLF hospitalizations were identified and infections were classified using validated algorithms, categorized as bacteremia, fungal, spontaneous bacterial peritonitis (SBP), pyelonephritis/urinary tract infection, or skin and soft tissue/musculoskeletal infection (SST/MSK). Inverse probability treatment weighing for infection-associated ACLF followed by multivariable logistic regression was used to evaluate the association between infection type and 90-day mortality. RESULTS: A total 22,589 ACLF hospitalizations were included, 3998 (17.7%) of which had ACLF grade 3. Infection was associated with 12,405 (54.9%) of ACLF hospitalizations. In regression models, SBP was associated with a 1.79-fold increased odds of 90-day mortality vs. no infection (95% confidence interval [CI] 1.58-2.02, p < 0.001), whereas SST/MSK infections had a lower relative odds of mortality (odds ratio 0.48, 95% CI 0.42-0.53, p < 0.001). There was a significant interaction between infection category and ACLF grade on the outcome of 90-day mortality (p < 0.001). CONCLUSIONS: The impact of infection on short-term mortality in ACLF varies depending on the source of infection. This has relevance for ACLF prognostication and challenges previous notions that bacterial infection invariably worsens prognosis among all patients with ACLF.