High prevalence of bla OXA-23 in Acinetobacter spp. and detection of bla NDM-1 in A. soli in Cuba: report from National Surveillance Program (2010-2012)

Abstract

As a first national surveillance of Acinetobacter in Cuba, a total of 500 Acinetobacter spp. isolates recovered from 30 hospitals between 2010 and 2012 were studied. Acinetobacter baumannii-calcoaceticus complex accounted for 96.4% of all the Acinetobacter isolates, while other species were detected at low frequency (A. junii 1.6%, A. lwoffii 1%, A. haemolyticus 0.8%, A. soli 0.2%). Resistance rates of isolates were 34-61% to third-generation cephalosporins, 49-50% to β-lactams/inhibitor combinations, 42-47% to aminoglycosides, 42-44% to carbapenems and 55% to ciprofloxacin. However, resistance rates to colistin, doxycycline, tetracycline and rifampin were less than 5%. Among carbapenem-resistant isolates, 75% harboured different bla OXA genes (OXA-23, 73%; OXA-24, 18%; OXA-58, 3%). The bla NDM-1 gene was identified in an A. soli strain, of which the species was confirmed by sequence analysis of 16S rRNA gene, rpoB, rpoB-rpoC and rpoL-rpoB intergenic spacer regions and gyrB. The sequences of bla NDM-1 and its surrounding genes were identical to those reported for plasmids of A. baumannii and A. lwoffi strains. This is the first report of bla NDM-1 in A. soli, together with a high prevalence of OXA-23 carbapenemase for carbapenem resistance in Acinetobacter spp. in Cuba.

Keywords: Acinetobacter; Cuba; NDM-1; OXA-23; carbapenem resistance.

Fig. 1

Schematic representation of surroundings of bla_NDM-1 in Acinetobacter soli strain CU244, based on determined sequence. For groEL, only 5′ side partial sequence was determined.