Clostridium difficile infection has gained importance in recent years as a result of the rapid spread of epidemic strains, including hypervirulent strains. This study reports the molecular epidemiology of C. difficile obtained from hospitalized patients in Chile. Seven hundred and nineteen isolates of toxigenic C. difficile from 45 hospitals across the country were characterized through toxin profile, pulsed-field gel electrophoresis (PFGE), and sequencing of the tcdC gene. In addition, polymerase chain reaction (PCR) ribotyping and multilocus sequence typing (MLST) were performed on a subset of selected strains. PFGE typing of 719 isolates of C. difficile produced 60 PFGE patterns (subtypes). Subtype 1 was predominant (79% of isolates) and related to the hypervirulent strain (NAP1). Subtype 1 showed 73% relatedness with nine other subtypes, which had a similar tcdC deletion. Subtype 1 corresponded to ribotype 027 and ST1. This report shows the wide dissemination of the hypervirulent strain NAP1/027/ST1 in Chile.
Keywords: Clostridium difficile; MLST; PFGE; ribotype.