[1] Univ Ulsan, Coll Med, Asan Med Ctr, Div Infect Dis, Seoul 138736, South Korea
[2] Univ Ulsan, Coll Med, Asan Med Ctr, Div Gastroenterol, Seoul 138736, South Korea
[3] Univ Ulsan, Coll Med, Asan Med Ctr, Dept Lab Med, Seoul 138736, South Korea
[4] Univ Ulsan, Ctr Antimicrobial Resistance & Microbial Genet, Seoul, South Korea