Virulence Diversity among Bacteremic Aeromonas Isolates: Ex Vivo, Animal, and Clinical Evidences

BackgroundThe objective of this study was to compare virulence among different Aeromonas species causing bloodstream infections.Methodology/Principal FindingsNine of four species of Aeromonas blood isolates, including A. dhakensis, A. hydrophila, A. veronii and A. caviae were randomly selected for analysis. The species was identified by the DNA sequence matching of rpoD. Clinically, the patients with A. dhakensis bacteremia had a higher sepsis-related mortality rate than those with other species (37.5% vs. 0%, P = 0.028). Virulence of different Aeromonas species were tested in C. elegans, mouse fibroblast C2C12 cell line and BALB/c mice models. C. elegans fed with A. dhakensis and A. caviae had the lowest and highest survival rates compared with other species, respectively (all P values A. dhakensis isolates also exhibited more cytotoxicity in C2C12 cell line (all P values A. dhakensis was lower than that of other species (all P values A. caviae isolates.Conclusions/SignificanceClinical data, ex vivo experiments, and animal studies suggest there is virulence variation among clinically important Aeromonas species.