Rapid dissemination of colistin and carbapenem resistant Acinetobacter baumannii in Central Greece: mechanisms of resistance, molecular identification and epidemiological data

Abstract

BackgroundColistin-resistant/carbapenem-resistant Acinetobacter baumannii is a significant challenge for antibiotic treatment and infection control policies. Since 2012, in Central Greece an increase of colistin/pan- resistant A. baumannii has occurred, indicating the need for further analysis.MethodsA total of 86 colistin-resistant/carbapenem-resistant out of 1228 A. baumannii clinical isolates, consecutively collected between 2012 and 2014 in a tertiary Greek hospital of Central Greece, as well as one environmental isolate from surveillance cultures were studied. Molecular typing and mechanisms of resistance to colistin and to carbapenems were assessed, whereas, epidemiological and clinical data of the patients were reviewed.ResultsDuring the study period, the rate of colistin resistance gradually increased and reached 21.1 % in 2014. All colistin-resistant/carbapenem-resistant A. baumannii belonged to 3LST ST101 clone that corresponds to the international clonal lineage II. Carbapenem resistance was associated with the presence of blaoxa-23-like, while resistance to colistin probably correlated with G54E and R109H amino acid substitutions in PmrA and PmrC, respectively.ConclusionsEpidemiological data of the patients indicated that the first detection of colistin-resistant/carbapenem-resistant ST101 clone in the University Hospital of Larissa (UHL) was associated with a patient who previously had received colistin, while, the movement of the infected patients into the hospital probably resulted to its spread.

Clinical and Pathophysiological Overview of Acinetobacter Infections: a Century of Challenges

“…These strains tend to be pan-resistant, with no available antibiotic therapies left. Tigecycline resistance now exceeds 50% in some regions, and polymyxin resistance rates as high as 20% have been seen in Greece, and are increasingly reported in other regions as well (189,249,(264)(265)(266). These pan-resistant isolates underscore the critical need to identify alternative therapeutic strategies.…”

Complicated urinary tract infection with Extensive Drug resistant Klebsiella pneumoniae treated with combinatorial therapy of CSE-1034 along with Carbapenems. A case report and the review of literature

“…Giani et al [4] have reported an outbreak of colistinresistant KPC-producing K. pneumoniae in 93 patients over 4 years from 2009 to 2012. In one of the surveillance studies between 2012 to 2014 in Greece, 86 colistin-resistant/carbapenem-resistant clinical isolates were reported [14]. Likewise, outbreaks of colistin-resistant, carbapenem-resistant Enterobacteriaceae cases have been reported worldwide including Israel involving 15 patients over 10 months in 2006 [15], South Korea [5], and Detroit [16].…”

Emergence of polymyxin resistance in Gram-negative bacteria

“…Giamarellou ('Epidemiology of infections caused by polymyxin-resistant pathogens') reviews the recent literature on the epidemiology of infections due to polymyxin-resistant Gram-negative bacteria in humans [8]. Polymyxin-resistant pathogens in clinical settings, such as Klebsiella pneumoniae and A. baumannii, may be concomitantly resistant to carbapenems [9,10]. New perspectives on how to safeguard polymyxins (e.g.…”