Molecular epidemiology and antimicrobial susceptibility profiles of Campylobacter jejuni isolated from bloodstream infections and enteritis in Japan.

Campylobacter enteritis (En) is the most frequently diagnosed bacterial En worldwide, including in Japan. Campylobacter spp. can also cause bloodstream infection (BSI), reactive arthritis, and Guillain-Barré syndrome. The purpose of this study was to clarify the characteristics of Campylobacter jejuni strains that cause BSI in comparison with En-causing strains. BSI strains (n = 40) and En strains that caused food poisoning (n = 67) were collected in Japan. Our study revealed that ST-4526 was predominant in BSI strains, and the overall distribution of sequence types was similar in both BSI and En strains. Differences in CPS type distribution might be related to the pathogenesis of bacteremia. Quinolone resistance rates were higher than those reported in previous studies, and strains resistant to both quinolones and tetracyclines were more frequently observed in BSI strains. Finally, we report a case of mixed infection with different STs in BSI.