Comparison of phylogenetic and virulence factors between isolated from biliary tract infections and uropathogenic .

is a gram-negative intestinal commensal that can also cause various infections, including urinary tract infections, biliary tract infections, neonatal meningitis, and septicemia. Although the characteristics of uropathogenic and the mechanisms of urinary tract infection have been well studied, the genetic distinctions among isolates from different types of infections have not yet been determined. This study compared the phylogenetic and virulence factors of isolates from bacteremic biliary tract infections with those from bacteremic urinary tract infections. The phylogenetic B2 group was the most prevalent in both pathogenic groups (68 % in biliary pathogenic isolates and 85 % in uropathogenic isolates), but the frequency pattern of the phylogenetic group was different. Half of the uropathogenic isolates belonged to ST95 and ST131 (51 %). Among the biliary pathogenic isolates, ST131 was the most prevalent, while the remaining half belonged to other STs outside the four major STs. The frequency of some virulence factors, such as , , , , , , , and was lower in the biliary pathogenic isolates than in the uropathogenic isolates. The frequency of phylogenetic groups and STs in MLST differed between isolates from bacteremic biliary tract infections and urinary tract infections. Additionally, some virulence factors, including adhesion and toxin gene groups, showed lower frequencies in the biliary pathogenic group than in the uropathogenic group. Studying the differences in pathovars from different infection sites is important for developing pathovar-specific targeted therapies such as vaccine therapy.