What Gram-negative (Gram negative) bacterium is involved in liver abscess?

From the Guidelines

The most common Gram-negative bacteria involved in liver abscesses is Escherichia coli (E. coli), as supported by recent studies 1. Other significant Gram-negative organisms include Klebsiella pneumoniae (particularly the hypervirulent strains common in Asia), Pseudomonas aeruginosa, Enterobacter species, and Proteus species. These bacteria typically reach the liver through the biliary tract in cases of cholangitis, via the portal venous system from intra-abdominal infections, or through hematogenous spread from distant infections. Klebsiella liver abscesses have become increasingly prevalent worldwide, with hypervirulent strains causing a distinct syndrome characterized by metastatic infections. Treatment typically involves drainage of the abscess combined with appropriate antibiotics such as third-generation cephalosporins, fluoroquinolones, or carbapenems, depending on local resistance patterns, as recommended by recent guidelines 1. The choice of antibiotic should cover both Gram-negative and anaerobic organisms, as liver abscesses are often polymicrobial. Antibiotic therapy usually continues for 4-6 weeks, with the first two weeks administered intravenously followed by oral therapy. It is essential to consider the increasing prevalence of multidrug-resistant Gram-negative bacteria, such as carbapenem-resistant Enterobacteriaceae (CRE), when selecting empirical antibiotic therapy 1. In cases of suspected or confirmed CRE infection, carbapenem-based empirical therapy may be associated with lower mortality and treatment failure rates compared to third-generation cephalosporin-based regimens 1. However, the use of carbapenems should be guided by local epidemiology, risk factors for multidrug-resistant bacteria, and severity of infection. Ultimately, the selection of antibiotics should be tailored to the individual patient's needs, taking into account the suspected or confirmed pathogen, local resistance patterns, and the patient's clinical condition.

From the FDA Drug Label

The FDA drug label does not answer the question.

From the Research

Gram-Negative Bacteria Involved in Liver Abscess

• The most common Gram-negative bacteria involved in liver abscess are:
  • Escherichia coli 2, 3
  • Klebsiella pneumoniae 2, 3, 4, 5, 6
  • Pseudomonas aeruginosa 2, 3
  • Acinetobacter baumannii 3

Characteristics of Klebsiella pneumoniae in Liver Abscess

• Klebsiella pneumoniae is a common cause of liver abscess, particularly in Southeast Asia 3, 4
• It is often associated with diabetes mellitus and can cause severe infections 3, 4, 5
• Klebsiella pneumoniae can produce extended-spectrum β-lactamase (ESBLs), making it resistant to certain antibiotics 3
• It is typically susceptible to third-generation cephalosporins, fluoroquinolones, and carbapenems 3, 6

Treatment of Liver Abscess Caused by Gram-Negative Bacteria

• Treatment typically involves a combination of antibiotics and percutaneous drainage of the abscess 2, 3, 5, 6
• Empirical therapy should include coverage for anaerobic bacteria and Gram-negative bacteria 2, 6
• The choice of antibiotics should be based on the susceptibility pattern of the isolated bacteria and the size of the abscess 3, 6