Article

Genotype and antibiotic susceptibility patterns of drug-resistant Pseudomonas aeruginosa and Acinetobacter baumannii isolates in Taiwan.

Department of Electronic Engineering, National Kaohsiung University of Applied Sciences, Kaohsiung, Taiwan, Republic of China.
Microbial drug resistance (Larchmont, N.Y.) (Impact Factor: 1.99). 01/2009; 14(4):281-8. DOI: 10.1089/mdr.2008.0861
Source: PubMed

ABSTRACT Rapid and accurate identification of the drug susceptibility profile of clinical strains is very important for controlling bacterial infections and determining the antibiotic therapy. The objective of this study was to investigate the spectrum of the correlation between phenotypic and genetic characters of the drug-resistant clinical isolates. A total of 133 clinical isolates, including 76 Acinetobacter baumannii and 57 Pseudomonas aeruginosa, were examined for their antibiotic susceptibility by the method of disc diffusion. Among them, most of the isolates were multiresistant, and 80% of the strains showed phenotypic resistance to beta-lactam antibiotics. Using PCR analysis, among the several types of beta-lactamases, TEM was the most prevalent, and OXA was the second most prevalent. The integron harbored was identified by conserved segment PCR, and 50% of the test isolates carried integrons with various gene cassette sizes inserted. The results obtained from this study reveal that the majority of these isolates displayed multiple drug resistance phenotypes that were associated with their mutational gene profiles.

0 Bookmarks
 · 
56 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A total of 62 Pseudomonas aeruginosa strains isolated from two hospitals in Siedlce (Poland) were studied by repetitive element based PCR (rep-PCR) using BOX primer. BOX-PCR results revealed the presence of 7 numerous genotypes and 31 unique patterns among isolates. Generally, the strains of P. aeruginosa were characterized by resistance to many antibiotics tested and by differences in serogroups and types of growth on cetrimide agar medium. However, the P. aeruginosa strains isolated from faeces showed much lower phenotypic and genotypic variations in comparison with strains obtained from other clinical specimens. It was observed that genetic techniques supported by phenotypic tests have enabled to conduct a detailed characterization of P. aeruginosa strains isolated from a particular environment at a particular time.
    Brazilian Journal of Microbiology 01/2012; 43(1):274-82. · 0.76 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Acinetobacter baumannii is an aerobic non-motile Gram-negative bacterial pathogen that is resistant to most antibiotics. Carbapenems are the most common antibiotics for the treatment of infections caused by this pathogen. Mechanisms of antibiotic-resistance in A. baumannii are mainly mediated by efflux pumps-lactamases. The aim of this study was to determine antibiotic susceptibility, the possibility of existence of OXAs genes and fingerprinting by Pulsed-Field Gel Electrophoresis (PFGE) among clinical isolates of Acinetobacter collected from Kermanshah hospitals. One hundred and four isolates were collected from patients attending Imam Reza, Taleghani and Imam Khomeini hospitals of Kermanshah (Iran). Isolates were identified by biochemical tests and API 20NE kit. The susceptibility to different antibiotics was assessed with Kirby-Bauer disk diffusion method. PCR was performed for detection of bla OXA-23, bla OXA-24, bla OXA-51 and bla OXA-58 beta-lactamase genes. Clonal relatedness was estimated by PFGE (with the restriction enzyme Apa I) and DNA patterns were analyzed by Gel compare II 6.5 software. All isolates showed high-level of resistance to imipenem, meropenem as well as to other antimicrobial agents, while no resistance to polymyxin B, colistin, tigecylcine and minocycline was observed. The bla OXA-23like and bla OXA-24 like were found among 77.9% and 19.2% of the isolates, respectively. All isolates were positive for bla OXA-51, but none produced any amplicon for bla OXA-58. PFGE genotype analysis suggested the existence of eight clones among the 104 strains [A (n = 35), B (n = 29), C (n = 19), D (n = 10), E (n = 4), F (n = 3), G (n = 3), H (n = 1)]. Clone A was the dominant clone in hospital settings particularly infection wards so that the isolates in this group, compared to the other clones, showed higher levels of resistance to antibiotics. The bla OXA-51-like and bla OXA-23like were the predominant mechanisms of resistance to imipenem in A. baumannii. A high prevalence of clone A, B and C in different parts of the healthcare system showed that hospitalized patients should be safeguarded to prevent the spread of these clones. Early recognition of the presence of carbapenem-resistant A. baumannii clones is useful for preventing their spread within the hospital environment.
    Iranian journal of microbiology. 09/2013; 5(3):195-202.
  • [Show abstract] [Hide abstract]
    ABSTRACT: The carbapenemases have recently emerged as molecules implicated in one of the most feared bacterial resistance mechanisms because of their ability to hydrolyze virtually all lactamase agents and their highly mobile genes. This study aimed to investigate the prevalence of carbapenemase and antimicrobial susceptibilities of Pseudomonas aeruginosa isolated from burn patients in Chongqing, China. Antimicrobial susceptibility of 111 isolates was determined by the disc agar diffusion test and the agar dilution method. Random Amplification of Polymorphic DNA polymerase chain reaction analysis revealed 111 P. aeruginosa 42 genotypes. Carbapenemase genes were amplified by polymerase chain reaction and the sequence verified by blast. Ninety-three of 111 (83.8%) isolates were resistant to imipenem; all of them had developed multidrug resistance and exhibited higher resistant rates compared with the imipenem-susceptible Pseudomonas. Ciprofloxacin was the most effective antipseudomonal agent. Thirty-three of the isolates were identified to contain the metallo-β-lactamase blaIMP-4 gene and belong to different Random Amplification of Polymorphic DNA polymerase chain reactiongenotypes. In conclusion, the high prevalence of multidrug resistance (94.6%) and the production of blaIMP-4 genes in P. aeruginosa isolates in burn patients highlight the necessity of considering these issues in burn hospitals.
    Journal of burn care & research: official publication of the American Burn Association 05/2013; · 1.54 Impact Factor