Molecular characterization of clinical multiresistant isolates of Acinetobacter sp. from hospitals in Porto Alegre, Brazil

Introduction : Hospitals around the world have presented multiresistant Acinetobacter sp. outbreaks. The spread of these isolates that harbor an increasing variety of resistance genes makes the treatment of these infections and their control within the hospital environment more difficult. This study aimed to evaluate the occurrence and dissemination of Acinetobacter sp. multiresistant isolates, and to identify acquired resistance genes.  Methods : We analyzed 274 clinical isolates of Acinetobacter sp.  from five hospitals in Porto Alegre, RS, Brazil. We evaluated the susceptibility to antimicrobial, acquired resistance genes from Ambler’s classes B and D and performed molecular typing of the isolates using ERIC-PCR technique.  Results : A high percentage (68%) of multiresistant isolates of Acinetobacter sp. was observed and 69% were resistant to carbapenems. We identified 84% of isolates belonging to species A. baumannii , since they presented the gene bla OXA-51 . The gene bla OXA-23  was detected in 62% of the isolates, and among these, 98% were resistant to carbapenems. Using the ERIC-PCR technique we identified clones of Acinetobacter sp. spread among the four hospitals analyzed during the sampling period. Conclusion : The data indicate the dissemination of Acinetobacter sp isolates among hospitals and their permanence in the hospital after one year.  Key words: Acinetobacter sp. bla OXA-23 , clonal dissemination, ERIC-PCR.