Successful application of the DiversiLab repetitive-sequence-based PCR typing system for confirmation of the circulation of a multiresistant Pseudomonas aeruginosa clone in different hospital wards.

The applicability of the repetitive-sequence-based PCR (rep-PCR)-based DiversiLab system was tested compared with the pulsed field gel electrophoresis (PFGE) to type a phenotypically similar subset of a large collection of multiresistant Pseudomonas aeruginosa strains isolated during a 17-month period from patients treated in different wards including 4 intensive care units (ICUs). Five environmental P. aeruginosa isolates obtained from one of the ICUs were also included. The DiversiLab system and the PFGE demonstrated the genetic relationship among the isolates with the same efficacy. One of the environmental isolates had the same rep-PCR type as the circulating clone. Multilocus sequence typing of one of the clinical isolates of the circulating clone proved that it is a member of a clonal complex of P. aeruginosa that has not been previously described in clinical samples.