Sir, Carbapenem resistance in Acinetobacter baumannii is now increasingly reported. The most prevalent mechanism of carbapenem resistance in A. baumannii corresponds to the production of acquired carbapenem-hydrolysing class D b-lactamases (CHDLs) encoded by blaOXA-23-like, blaOXA-40-like or blaOXA-58-like genes. Whereas the blaOXA-40 gene has been detected in Portugal, Spain and the USA, blaOX...

We read with great interest C. S. Antonio et al.’s letter describing the high prevalence of Acinetobacter baumannii carrying blaOXA-143 in Brazilian hospitals (1). Recently, we carried out a similar study, and although the blaOXA-143 gene was identified, its frequency was lower than that reported by Antonio et al. (1). During 2008, a total of 803 Gram-negative bacillus isolates, 1 isolate per p...

Sir, Acinetobacter bereziniae, previously known as Acinetobacter genomic species 10, has been isolated primarily from clinical specimens and the hospital environment and more rarely from various other sources, including vegetables, soil and animals. Antibiotic resistance is rarely reported in this species. Over the last decade, carbapenem resistance in Acinetobacter spp., mainly Acinetobacter b...

Over the last decade, nosocomial infections with Acinetobacter baumannii have been described with an increasing trend toward multidrug resistance, mostly in intensive care units (ICUs) (6, 9, 11). The main mechanism of resistance to carbapenems in A. baumannii is the production of acquired OXA-type carbapenemases, which have been frequently identified worldwide and are clustered in three major ...

Sir, Isolates from a collection of 177 antibiotic-resistant Acinetobacter recovered at Westmead Hospital, Sydney over the period 1995– 2002 were further characterized. The relationships among these isolates had previously been examined by PFGE of ApaI-digested DNA, determination of MICs of several antibiotics and PCR screening to determine whether the blaOXA-23 gene or class 1 integrons were pr...

Sir, Since its discovery in 2008, the metallo-b-lactamase (MBL) NDM-1 has been identified in different Enterobacteriaceae species and recently also in a number of other bacterial species isolated from water supplies in India, such as Vibrio cholerae and Pseudomonas spp. Genes encoding NDM b-lactamases have been additionally identified in multidrugresistant Acinetobacter spp. Here, we report on ...

The genus Acinetobacter comprises several groups of closely related species, including the Acinetobacter calcoaceticus-Acinetobacter baumannii complex (1) and a number of hemolytic species (2). Currently, the A. calcoaceticus-A. baumannii complex comprises five validly named species, including A. calcoaceticus, A. baumannii, A. pittii, and A. nosocomialis (3); the recently named species A. seif...

Acinetobacter baumannii is frequently associated with nosocomial infections, and its increasing resistance to carbapenems may significantly reduce the choice of effective antibiotics (2). Since the first description of a carbapenem-hydrolyzing class D -lactamase (CHDL), ARI-1 (renamed OXA-23), from a clinical isolate of A. baumannii in Scotland in 1995 (11), the corresponding blaOXA-23 gene has...

Infections due to multidrugand carbapenem-resistant isolates of Acinetobacter baumannii were frequent among patients treated in the Tzannion General Hospital in Piraeus, Greece, throughout the period 2005 to 2006. Six of these isolates, derived from blood cultures of patients in three different wards (four were from patients in the intensive care unit) and taken at least 1 month apart from each...