Genomic and Clinical Characterization of IMP-1-Producing Multidrug-Resistant <i>Acinetobacter bereziniae</i> Isolates from Bloodstream Infections in a Brazilian Tertiary Hospital

Abstract

<i>Acinetobacter baumannii</i> is the main species of the <i>Acinetobacter</i> genus; however, non-<i>baumannii Acinetobacter</i> (NBA) species causing infections have been described for the past years, as well as antimicrobial resistance. In this study, we describe the occurrence of two multidrug-resistant (MDR) IMP-1-producing <i>Acinetobacter bereziniae</i> isolates recovered from bloodstream infections in different patients but in the same intensive care unit among 134 carbapenem-resistant <i>Acinetobacter</i> screened. Antimicrobial susceptibility testing revealed resistance to carbapenems, extended spectrum, and antipseudomonad cephalosporins, amikacin, and trimethoprim-sulfamethoxazole. Both <i>A. bereziniae</i> isolates shared the same <i>Apa</i>I-pulsed-field gel electrophoresis (PFGE) pattern. Whole-genome sequencing of both isolates revealed that <i>bla</i>_IMP-1 was embedded into an In86 Class I integron carrying also <i>sul1</i>, <i>aac(6')-31</i>, and <i>aadA</i> genes. A new sequence type (ST1309 Pasteur) was deposited. The virulence genes <i>lpxC</i> and <i>ompA</i>, seen in <i>A. baumannii</i>, were detected in the <i>A. bereziniae</i> strains. Recognition of <i>A. bereziniae</i> causing invasive MDR infection underscores the role of NBA species as human pathogens especially in at-risk patients.