Molecular Relatedness of Typhimurium Isolates from Feces and an Infected Surgical Wound.

Purpose: serovar Typhimurium infection is common in foodborne diseases, but its isolation from surgical incisions is rare. Our aim in this study was to trace the transmission source of a surgical incision infected with . Typhimurium in a Yunnan Province hospital patient and elucidate the underlying molecular mechanisms of antibiotic resistance.

Methods: Primers were designed to amplify the drug-resistance genes using polymerase chain reaction (PCR). Susceptibility to antibiotics was determined using Etest strips. Macrorestriction profiles were analyzed using pulsed-field gel electrophoresis (PFGE) and XbaI. The two isolates were characterized using agglutination tests and multilocus sequence typing (MLST).

Results: MLST analysis revealed that . Typhimurium isolates SM043 and SM080 belonged to the same genotype, ST34, and PFGE revealed that SM043 and SM080 had high similarity. The isolates were both resistant to third-generation cephalosporins. SM043 harbored the antibiotic resistance genes , and , whereas , and were detected in SM080.

Conclusion: The surgical incision infection by . Typhimurium may have been hospital-acquired. Thus, it is critical to strengthen hospital sanitation by addressing hand hygiene and sterilization of the operational environment to avoid outbreaks of nosocomial infections.