Abstract
BACKGROUND: Biliary tract infection (BTI) is a common cause of bacteremia, and is associated with high morbidity and mortality. The clinical epidemiology and outcomes of BTI caused by Klebsiella pneumoniae (KP) have not been well investigated. METHODS: This was a retrospective study performed at a university teaching hospital in China from May 2012 to June 2017 that analyzed data for 119 patients with BTI caused by KP. We identified KP from bile cultures obtained before endoscopic or surgical treatment. Patients' demographic characteristics and clinical outcomes were also recorded. RESULTS: Forty-seven KP strains (39.5%) were positive for the extended spectrum beta-lactamase (ESBL) phenotype. The ESBL-positive group had a higher rate of stay in ICU [12.8% vs. 1.4% (ESBL-negative group); P=0.015] and a significantly longer hospital stay (30.79±31.512 vs. 20.06±23.945 days, respectively; P=0.037). There were no significant differences for 30-day mortality between the two groups; 112 (94.1%) patients survived and 7 (5.9%) died within 30-days of onset. Univariate analysis showed that nonsurvivors were significantly more likely to be older (66.46±22.34 vs. 46±14.84 years, respectively; P=0.001), and have hypoproteinemia (5/7, 71.4% vs. 21/112, 18.8%; P=0.006), immunosuppression (3/7, 42.9% vs. 4/112, 3.6%; P=0.004), solid tumors (5/7, 71.4% vs. 20/112, 17.9%; P=0.004), bloodstream infections (6/7, 85.7% vs. 22/112, 19.6%; P=0.001), and lower surgery rates (1/7, 14.3% vs. 66/112, 58.9%; P=0.042) compared with survivors, respectively. However, we found no significant independent risk factor for mortality. The malignant biliary obstruction group was significantly more likely to have chronic liver disease (P=0.035) than the benign biliary obstruction group, and mortality was higher for the malignant biliary obstruction group (5/25, 20% vs. 2/94, 2.1%, respectively; P=0.05). The malignant biliary group also had higher alkaline phosphatase, and direct and total bilirubin direct levels. Multivariate analysis showed that chronic liver disease was an independent risk factor in patients with malignant biliary disease [odds ratio (OR), 2.431; 95% confidence interval, 1.834-4.031; P=0.001]. CONCLUSIONS: Patients with BTI caused by KP were more likely to have the ESBL phenotype, and antibiotic resistance was not associated with overall survival. Patients with malignant biliary obstruction had higher mortality, and chronic liver disease was an independent risk factor.