Pyogenic liver abscesses in liver transplant recipients versus non-transplant population. Outcome and risk factors of patient survival

Pyogenic liver abscess (PLA) is a life-threatening infection in both liver transplant (LT) and non-LT patients. Several risk factors, such as benign and malignant hepatopancreatobiliary diseases and colorectal tumors have been associated with PLA in the non-LT population, and hepatic artery stricture/thrombosis, biliary stricture, and hepaticojejunostomy in the LT patients. The objective of this study is to compare the outcomes of patients with PLA in LT and non-LT patients and to determine the risk factors associated with patient survival. From January 2000 to November 2020, a total of 296 adult patients were diagnosed of PLA in our institution, of whom 26 patients had previously undergone liver transplantation (LTA group), whereas 263 patients corresponded to the non-LTA population. Seven patients with PLA who had undergone previous kidney transplantation were excluded from this retrospective study. Twenty-six patients out of 1503 LT developed PLA (incidence of 1.7%). Median age was significantly higher in non-LTA patients (p = .001). No significant differences were observed in therapy. PLA recurrence was significantly higher in LTA than in non-LTA (34.6% vs. 14.8%; p = .008). In-hospital mortality was greater in the LT group than in the non-LT group (19.2% vs. 9.1% p = .10) and was identified in multivariable analysis as a risk factor for mortality (p = .027). Mortality rate during follow-up did not show significant differences between the groups: 34.6% in LTA patients versus 26.2% in non-LTA patients (p = .10). The most common causes of mortality during follow-up were malignancies, Covid-19 infection, and neurologic disease. 1-, 3-, and 5-year actuarial patient survival rates were 87.0%, 64.1%, and 50.4%, respectively, in patients of LTA group, and 84.5%, 66.5%, and 51.0%, respectively, in patients with liver abscesses in non-LTA population (p = .53). In conclusion, LT was a risk factor for in hospital mortality, but not during long-term follow-up.