Risk factors and outcomes of pyogenic liver abscess in adult liver recipients: a matched case-control study

Background: Adult liver recipients (ALR) differ from the general population with pyogenic liver abscess (PLA) as they exhibit: reconstructed biliary anatomy, recurrent hospitalizations, poor clinical condition and are subjected to immunosuppression. The aim of this study was to identify risk factors associated with PLA in ALR and to analyze the management experience of these patients. Methods: Between 1996 and 2016, 879 adult patients underwent liver transplantation (LT), 26 of whom developed PLA. Patients and controls were matched according to the time from transplant to abscess in a 1 to 5 relation. A logistic regression model was performed to establish PLA risk factors considering clusters for matched cases and controls. Risk factors were identified and a multivariate regression analysis performed. Results: Patients with post-LT PLA were more likely to have lower BMI (p = 0.006), renal failure (p = 0.031) and to have undergone retransplantation (p = 0.002). A history of hepatic artery thrombosis (p = 0.010), the presence of Roux en-Y hepatojejunostomy (p < 0.001) and longer organ ischemia time (p = 0.009) were independent predictors for the development of post-LT PLA. Five-year survival was 49% (95% CI 28-67%) and 89% (95% CI 78%-94%) for post-LT PLA and no post-LT PLA, respectively (p < 0.001). Conclusion: history of hepatic artery thrombosis, the presence of hepatojejunostomy and a longer ischemia time represent independent predictors for the development of post-LT PLA. There was a significantly poorer survival in patients who developed post-LT PLA compared with those who did not.