Clonal diversity of Acinetobacter baumannii clinical isolates revealed by a snapshot study

<jats:title>Abstract</jats:title> <jats:sec> <jats:title>Background</jats:title> <jats:p> <jats:italic>Acinetobacter baumannii</jats:italic> is a notorious opportunistic pathogen mainly associated with hospital-acquired infections. Studies on the clonal relatedness of isolates could lay the foundation for effective infection control. A snapshot study was performed to investigate the clonal relatedness of <jats:italic>A</jats:italic>. <jats:italic>baumannii</jats:italic> clinical isolates in our local settings.</jats:p> </jats:sec> <jats:sec> <jats:title>Results</jats:title> <jats:p>Among 82 non-repetitive <jats:italic>Acinetobacter</jats:italic> spp. clinical isolates that were recovered during a period of four days in 13 hospitals in Sichuan, Southwest China, 67 isolates were identified as <jats:italic>A. baumannii</jats:italic>. Half of the 67 <jats:italic>A. baumannii</jats:italic> isolates were non-susceptible to carbapenems. <jats:italic>bla</jats:italic> <jats:sub>OXA-23</jats:sub> was the only acquired carbapenemase gene detected, present in 40 isolates including five carbapenem-susceptible ones. The isolates belonged to 62 pulsotypes determined by PFGE and 31 sequence types (ST) by multi-locus sequence typing. Forty-three isolates belonged to the globally-disseminated clonal complex 92, among which ST75, ST92 and ST208 were the most common sequence types.</jats:p> </jats:sec> <jats:sec> <jats:title>Conclusions</jats:title> <jats:p>Clinical isolates of <jats:italic>A. baumannii</jats:italic> were diverse in clonality in this snapshot study. However, most of the isolates belonged to the globally-distributed clonal complex CC92. ST75, ST92 and ST208 were the most common types in our region. In particular, ST208 might be an emerging lineage carrying <jats:italic>bla</jats:italic> <jats:sub>OXA-23</jats:sub>.</jats:p> </jats:sec>