Comparison of Antimicrobial Resistance of <i>Acinetobacter baumannii</i> Clinical Isolates from Shanghai and Hong Kong

The development of multidrug-resistant Acinetobacter baumannii is of serious concern in the hospital setting. Here, we report draft genome sequences of 11 A. baumannii isolates that were isolated from a single patient over a 65-day period, during which time the isolates exhibited increased antimicrobial resistance.

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Comparison of Genospecies and Antimicrobial Resistance Profiles of Isolates in the Acinetobacter calcoaceticus-Acinetobacter baumannii Complex from Various Clinical Specimens

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01304-12 ◽

2012 ◽

Vol 56 (12) ◽

pp. 6267-6271 ◽

Cited By ~ 9

Author(s):

Ni Tien ◽

Bang-Jau You ◽

Hui-Lan Chang ◽

Hsiu-Shen Lin ◽

Chin-Yi Lee ◽

...

Keyword(s):

Antimicrobial Resistance ◽

Acinetobacter Baumannii ◽

Restriction Analysis ◽

Acinetobacter Calcoaceticus ◽

Its Region ◽

Clinical Isolates ◽

23S Rrna ◽

Rrna Gene ◽

Genotype 3 ◽

Content Type

ABSTRACTThis study was conducted to compare the prevalences of antimicrobial resistance profiles of clinical isolates in theAcinetobacter calcoaceticus-Acinetobacter baumanniicomplex from sterile and nonsterile sites and to further study the relationship of antimicrobial resistance profiles and genospecies by amplified rRNA gene restriction analysis (ARDRA). A total of 1,381 isolates were tested with 12 different antibiotics to show their antimicrobial susceptibility profiles. A total of 205 clinical isolates were further analyzed by ARDRA of the intergenic spacer (ITS) region of the 16S-23S rRNA gene. It was found that the overall percentage of isolates from nonsterile sites (urine, sputum, pus, or catheter tip) that were resistant to the 12 antibiotics tested was significantly higher than that of isolates from sterile sites (cerebrospinal fluid [CSF], ascites fluid, and bloodstream) (46% versus 22%;P< 0.05). After ARDRA, it was found that 97% of the 62 isolates resistant to all antibiotics tested were theA. baumanniigenospecies, which was identified in only 31% of the isolates susceptible to all antibiotics tested. More genospecies diversity was identified in the isolates susceptible to all antibiotics tested, including genospecies of 13TU (34%), genotype 3 (29%), andA. calcoaceticus(5%). Furthermore, as 91% (10/11) of the isolates from CSF were susceptible to all antibiotics tested, theA. calcoaceticus-A. baumanniicomplex isolates with multidrug resistance could be less invasive than the more susceptible isolates. This study also indicated current emergence of carbapenem-, fluoroquinolone-, aminoglycoside-, and cephalosporin-resistantA. calcoaceticus-A. baumanniicomplex isolates in Taiwan.

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Carbapenem-susceptible Acinetobacter baumannii carrying the ISAba1 upstream blaOXA-51-like gene in Porto Alegre, southern Brazil

Epidemiology and Infection ◽

10.1017/s095026881200074x ◽

2012 ◽

Vol 141 (2) ◽

pp. 330-333 ◽

Cited By ~ 14

Author(s):

M. PAGANO ◽

A. F. MARTINS ◽

A. B. M. P. MACHADO ◽

J. BARIN ◽

A. L. BARTH

Keyword(s):

Antimicrobial Resistance ◽

Acinetobacter Baumannii ◽

Clinical Isolates ◽

High Morbidity ◽

Southern Brazil ◽

Porto Alegre ◽

Integrase Gene ◽

Carbapenem Resistant ◽

High Prevalence ◽

Class 1

SUMMARYOver the last decade, Acinetobacter baumannii resistant to carbapenems has emerged in many medical centres and is commonly associated with high morbidity and mortality. We investigated potential mechanisms contributing to antimicrobial resistance of 58 clinical isolates of A. baumannii collected during a prolonged city-wide outbreak in five different hospitals in southern Brazil. The integrase gene was detected in 51 (87·9%) isolates of which 36 harboured class 2 integrons alone and 14 had both class 1 and 2 integrons; all carbapenem-resistant isolates displayed class 2 integrons. ISAba1 was found upstream of blaOXA-23-like only in isolates resistant to carbapenems; however, ISAba1 upstream of blaOXA-51-like was present in both susceptible and resistant isolates. This is the first report of a high prevalence of class 2 integrons in A. baumannii in southern Brazil. Moreover, our study suggests that ISAba1/blaOXA-51-like alone is insufficient to confer resistance to carbapenems.

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Molecular epidemiology and antimicrobial resistance features of Acinetobacter baumannii clinical isolates from Pakistan

Annals of Clinical Microbiology and Antimicrobials ◽

10.1186/s12941-019-0344-7 ◽

2020 ◽

Vol 19 (1) ◽

Cited By ~ 2

Author(s):

Nabil Karah ◽

Fizza Khalid ◽

Sun Nyunt Wai ◽

Bernt Eric Uhlin ◽

Irfan Ahmad

Keyword(s):

Antimicrobial Resistance ◽

Molecular Epidemiology ◽

Acinetobacter Baumannii ◽

Resistance Genes ◽

Antimicrobial Agents ◽

Opportunistic Pathogen ◽

Clinical Isolates ◽

Diffusion Method ◽

Agar Disc ◽

Antimicrobial Resistance Genes

Abstract Background Acinetobacter baumannii is a Gram-negative opportunistic pathogen with a notorious reputation of being resistant to antimicrobial agents. The capability of A. baumannii to persist and disseminate between healthcare settings has raised a major concern worldwide. Methods Our study investigated the antibiotic resistance features and molecular epidemiology of 52 clinical isolates of A. baumannii collected in Pakistan between 2013 and 2015. Antimicrobial susceptibility patterns were determined by the agar disc diffusion method. Comparative sequence analyses of the ampC and blaOXA-51-like alleles were used to assign the isolates into clusters. The whole genomes of 25 representative isolates were sequenced using the MiSeq Desktop Sequencer. Free online applications were used to determine the phylogeny of genomic sequences, retrieve the multilocus sequence types (ST), and detect acquired antimicrobial resistance genes. Results Overall, the isolates were grouped into 7 clusters and 3 sporadic isolates. The largest cluster, Ab-Pak-cluster-1 (blaOXA-66 and ISAba1-ampC-19) included 24 isolates, belonged to ST2 and International clone (IC) II, and was distributed between two geographical far-off cities, Lahore and Peshawar. Ab-Pak-clusters-2 (blaOXA-66, ISAba1-ampC-2), and -3 (blaOXA-66, ISAba1-ampC-20) and the individual isolate Ab-Pak-Lah-01 (ISAba1-blaOXA-66, ISAba1-ampC-2) were also assigned to ST2 and IC II. On the other hand, Ab-Pak-clusters-4 (blaOXA-69, ampC-1), -5 (blaOXA-69, ISAba1-ampC-78), and -6A (blaOXA-371, ISAba1-ampC-3) belonged to ST1, while Ab-Pak-cluster-6B (blaOXA-371, ISAba1-ampC-8) belonged to ST1106, with both ST1 and ST1106 being members of IC I. Five isolates belonged to Ab-Pak-cluster-7 (blaOXA-65, ampC-43). This cluster corresponded to ST158, showed a well-delineated position on the genomic phylogenetic tree, and was equipped with several antimicrobial resistance genes including blaOXA-23 and blaGES-11. Conclusions Our study detected the occurrence of 7 clusters of A. baumannii in Pakistan. Altogether, 6/7 of the clusters and 45/52 (86.5%) of the isolates belonged to IC I (n = 9) or II (n = 36), making Pakistan no exception to the global domination of these two clones. The onset of ST158 in Pakistan marked a geographical dispersal of this clone beyond the Middle East and brought up the need for a detailed characterization.

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