Polymicrobial and ESBL-Producing Bacterial Infections Among Pyogenic Liver Abscess: A 12-Year Study of Risk Factors...

Pyogenic liver abscess (PLA) is a potentially life-threatening hepatic infection. The increasing prevalence of polymicrobial infections and multidrug-resistant (MDR) pathogens, including extended-spectrum β-lactamase (ESBL)-producing bacteria, poses challenges to treatment and association with higher mortality rates. Identifying risk factors and optimizing clinical management strategies for these infections are essential to improving patient outcomes.

This retrospective study analyzed the clinical data of 643 PLA patients admitted in recent 12 years. Univariate and multivariate analyses were conducted to analyze treatment strategies, disease burden, and clinical outcomes, as well as identify risk factors associated with polymicrobial infections and ESBL-producing bacterial strains.

In this study, 255 of 643 PLA patients with positive bacterial identification were enrolled. Among them, 41 had polymicrobial infections. Of the 162 patients who underwent ESBL testing, 128 were infected with ESBL-producing bacteria. Polymicrobial PLA was significantly associated with intra-abdominal trauma or surgery (odds ratio [OR] = 3.06), malignancies or hematological diseases (OR = 3.01). ESBL-producing bacterial PLA was correlated with hepatic tenderness (OR = 3.24), intra-abdominal trauma or surgery (OR = 3.06), and hospitalization within the past three months (OR = 4.32). E. coli was more frequently identified among ESBL-producing bacteria compared to K. pneumoniae. The use of carbapenems for treating ESBL-producing pathogens has been increasing, with carbapenems and β-lactamase inhibitor combinations currently serving as the primary therapeutic options.

Patients with PLA who have a history of intra-abdominal trauma or surgery, malignancies or hematological diseases, and recent hospitalization should be closely monitored for polymicrobial and drug-resistant infections. Given the high prevalence of antibiotic-resistant E. coli in PLA cases, judicious use of antibiotics is warranted. Broad-spectrum antibiotics effective against ESBL-producing bacteria should be considered, with carbapenems remaining the first-line treatment option.