Unique characteristics of pyogenic liver abscesses of biliary origin.

BACKGROUND: Pyrogenic liver abscesses (PLA) can be caused by cholangitis associated with hepatolithiasis and cholangitis related to an abnormal bilioenteric communication, such as a hepaticojejunostomy or the presence of indwelling biliary stents. Our aim was to evaluate the clinical characteristics of PLA of biliary origin.

METHODS: We compared patients with PLA related to biliary tract disease (PLA-B; n = 125) with patients with PLA not related to biliary tract disease (PLA-NB; n = 444). We also separated the patients with PLA-B into PLA related to biliary tract disease that involved an abnormal bilioenteric communication, including hepaticojejunostomy and indwelling biliary stents (PLA-B-AC; n = 38), and PLA-B not related to abnormal communication (n = 87), and compared them.

RESULTS: Among the 569 patients with PLA from 2008 to 2013, the most common etiologies were cryptogenic (n = 341; 60%) and biliary (n = 125; 22%). Patients with PLA-B tended to have a higher maximum body temperature and a greater leukocytosis. The incidences of bacteremia, septic shock, death, and postdischarge recurrence were greater in the PLA-B group when compared with the PLA-NB group. The most commonly isolated pathogenic bacteria in PLA-B group were Escherichia coli (36%) and Klebsiella pneumonia (23%). In contrast, in the PLA-NB group, the most common pathogen was K pneumonia (64%), whereas E coli was uncommon (only 5%). Independent risk factors for the occurrence of PLA-B were isolates with multidrug resistant (MDR) bacteria, bacteremia, E coli, and polymicrobial infection. In the group of PLA-B-AC, risk factors included MDR bacteria and a history of malignancy.

CONCLUSION: The occurrences of PLA-B are often infected with MDR bacteria and mixed infections caused mainly by E coli and other isolates and associated with bacteremia; PLA-B-AC are associated with MDR bacteria and a history of malignancy.