Liver abscess due to Klebsiella pneumoniae: Risk factors for metastatic infection

Introduction: Klebsiella pneumoniae-associated liver abscess (KPLA) is often accompanied by extrahepatic complications. We investigated the clinical features and outcomes of patients with and without metastatic infections and compared the 2 groups. Methods: We retrospectively reviewed the medical records of 161 patients with KPLA who were admitted to 2 tertiary referral hospitals in Korea. Results: In total, 9.9% had a metastatic infection. The most commonly involved distant sites were the eyes (n = 7) and the lungs (n = 6). In multivariate analysis, diabetes mellitus as an underlying disease (odds ratio (OR) 2.30, 95% confidence interval (CI) 1.05-9.51; p = 0.03) and a platelet count < 80,000/mm³ (OR 11.60, 95% CI 2.53-53.26; p = 0.002) were associated with metastatic infection. Extended-spectrum beta-lactamase (ESBL) production was not observed in K. pneumoniae from patients with metastatic infection, whereas 3.4% of the bacteria in patients without metastatic infection had ESBL production. However, this difference was not statistically significant (p = 0.45). The in-hospital mortality rate was not significantly different (0% vs. 2.8%; p = 0.52). By multivariate analysis, the Acute Physiology and Chronic Health Evaluation II (APACHE II) score was independently associated with mortality among patients with KPLA (OR 1.5, 95% CI 1.12-2.00; p = 0.006). Conclusions: Clinicians must be aware of potential metastatic infections in patients with KPLA, especially if they have diabetes mellitus and thrombocytopenia. The APACHE II score was predictive of mortality in patients with KPLA.