Carlos Hernán RodríguezNorah Balderrama YarhuiMarcela NastroTamara Nuñez QuezadaGlenda Castro CañarteRaquel Magne VenturaTayita Ugarte CubaNatalia ValenzuelaFreddy RoachMaría Inés Mota2026-03-222026-03-22201610.1099/jmm.0.000328https://doi.org/10.1099/jmm.0.000328https://andeanlibrary.org/handle/123456789/44353Citaciones: 73One hundred and twenty-six epidemiologically sequential, unrelated, carbapenem-resistant Acinetobacter baumannii isolates from nine hospitals in six countries of South America were collected between July 2013 and June 2014. Genes coding for Ambler class D and B carbapenemases were sought by PCR. All isolates were typed using the 3-locus sequence typing and blaOXA-51-like sequence-based typing techniques. The blaOXA-23 gene was recovered in all the participating hospitals and in all the isolates of seven of nine medical centres. The blaOXA-72 gene was only recovered in the two medical centres from Guayaquil city, Ecuador. Trilocus sequence typing revealed the presence of sequence groups SG2, SG4 and SG5. blaOXA-51-like sequence-based typing revealed the presence of blaOXA-132, blaOXA-65, blaOXA-69 and blaOXA-64. Our results showed that the population of carbapenem-resistant A. baumannii in South America was principally associated with ST79, ST25 and ST15 (92 %) and harboured the blaOXA-23 gene mainly. CC2 was not detected.enAcinetobacter baumanniiTypingBiologyMultilocus sequence typingMicrobiologyMolecular epidemiologyCarbapenemLocus (genetics)GeneInsertion sequencearticle