A new therapeutic challenge for old pathogens: community-acquired invasive infections caused by ceftriaxone- and ciprofloxacin-resistant Salmonella enterica serotype choleraesuis.

Recently, antimicrobial resistance among nontyphoid Salmonella serotypes has been increasingly recognized. In southern Taiwan, we encountered 3 cases of invasive infections caused by Salmonella enterica serotype Choleraesuis with resistance to ciprofloxacin and ceftriaxone. Resistance to ciprofloxacin was related to nucleotide mutations in gyrA and parC, and resistance to ceftriaxone was related to the presence of CMY-2 beta -lactamase.