Clinical and bacteriological characteristics of pyogenic liver abscess in non-diabetic patients

Background and purpose: Diabetes mellitus is an important risk factor for Klebsiella pneumoniae liver abscess, but many patients with pyogenic liver abscess (PLA) do not have diabetes. This study was conducted to compare the clinical characteristics and prognostic factors of K. pneumoniae PLA with that caused by other organisms in non-diabetic patients. Methods: The medical charts of patients with a diagnosis of PLA were retrospectively reviewed from January 2005 to December 2007. The clinical symptoms and signs, laboratory data, and risk factors were analyzed. Results: There were 50 patients in the K. pneumoniae group and 34 patients in the non-K. pneumoniae group. The clinical presentations did not differ between the 2 groups. The patients in the non-K. pneumoniae group had a higher prevalence of malignant disease than those in the K. pneumoniae group (58.8% vs 6.0%; p < 0.001). Non-K. pneumoniae PLA was strongly associated with hepatobiliary tumor (p = 0.015). Among the non-K. pneumoniae isolates, Escherichia coli was the most common pathogen (n = 20; 58.8%). Forty seven K. pneumoniae isolates (94%) were susceptible to all tested antimicrobial agents except ampicillin, while the non-K. pneumoniae Gram-negative pathogens had greater resistance to first-generation cephalosporins. Poor prognostic factors included chronic renal failure (p = 0.005), abscess rupture (p = 0.036), and right lower lung infiltration (p = 0.049). Conclusions: Hepatobiliary malignancy and newly diagnosed malignancy were risk factors for non-K. pneumoniae liver abscess in non-diabetic patients. Physicians should ascertain the presence of underlying malignancy in patients with non-K. pneumoniae PLA.