Spread of low-level carbapenem-resistant Acinetobacter baumannii clones in a tertiary care Greek hospital

1Department of Microbiology, Faculty of Nursing, School of Health Sciences, University of Athens, 123 Papadiamantopoulou Street, 11527 Athens; 2Department of Microbiology, Hippokration University Hospital, Thessaloniki; 3Department of Medical Microbiology, University of Thessalia, Larissa, Greece Sir, Acinetobacter spp. are opportunistic pathogens with increasing relevance in nosocomial infections, especially among immunocompromised patients. Extensive use of antimicrobial chemotherapy for these infections has contributed to the emergence and increase of multidrug-resistant Acinetobacter spp., such as Acinetobacter baumannii strains, in various hospitals. Such strains frequently exhibit resistance to β-lactams, aminoglycosides and fluoroquinolones. Carbapenems usually retain good potency, with imipenem being the most active against A. baumannii.1 However, in the last few years, carbapenem-resistant A. baumannii isolates have also been reported.2 Such strains exhibit various levels of susceptibility and owe their resistance either to target inaccessibility or to drug inactivation by β-lactamases. We report the spread of low-level carbapenem-resistant A. baumannii clones in a tertiary care university Greek hospital.