• J Microbiol Immunol Infect · Jun 2012

    Phenotypic detection and polymerase chain reaction screening of extended-spectrum β-lactamases produced by Pseudomonas aeruginosa isolates.

    • Shih-Ping Lin, Meei-Fang Liu, Chin-Fu Lin, and Zhi-Yuan Shi.
    • Section of Infectious Diseases, Department of Internal Medicine, Taichung Veteran General Hospital, Taiwan.
    • J Microbiol Immunol Infect. 2012 Jun 1; 45 (3): 200-7.

    Background/PurposeA growing number of β-lactamases have been reported in Pseudomonas aeruginosa isolates. The aims of this study were to survey the types of extended-spectrum β-lactamases (ESBLs) by polymerase chain reaction (PCR), to evaluate the reliability of phenotypic tests for ESBLs, and to identify the clonal distribution by pulsed-field gel electrophoresis (PFGE) among P. aeruginosa isolates resistant to expanded-spectrum cephalosporins (ceftazidime, aztreonam, or cefepime).MethodsThe antimicrobial susceptibility of 57 P. aeruginosa isolates from blood specimens were examined according to the recommendations of the Clinical Laboratory Standards Institute. ESBL phenotypes were determined by using cloxacillin-containing double disc synergy test (DDST). The existence of 11 β-lactamase genes was detected by PCR.ResultsOf the 57 P. aeruginosa isolates, 35 (61.4%) isolates were PCR-positive for β-lactamase genes. Twelve of 35 isolates were PCR-positive for combination of ampC and ESBL genes, including TEM, GES, SHV, VEB and OXA-I genes. The sensitivity and specificity of cloxacillin-containing DDST (using the criteria of ceftazidime zone diameter increased ≧5 mm) were 84.1% and 54.5%, respectively. Nine clusters were classified among 35 PCR-positive isolates by PFGE. Isolates of clusters B and C were distributed in different wards of this hospital during a period of 3-4 years.ConclusionESBL genes are not uncommon in P. aeruginosa isolates. Cloxacillin-containing DDST can enhance the sensitivity and has a potential role for phenotypic detection of ESBL-producing P. aeruginosa, and PCR is also helpful for the identification of specific β-lactamase genes. These P. aeruginosa isolates were classified into several diverse clones which could continue to spread in the hospital over a long period of time.Copyright © 2012. Published by Elsevier B.V.

      Pubmed     Free full text   Copy Citation     Plaintext  

      Add institutional full text...

    Notes

     
    Knowledge, pearl, summary or comment to share?
    300 characters remaining
    help        
    You can also include formatting, links, images and footnotes in your notes
    • Simple formatting can be added to notes, such as *italics*, _underline_ or **bold**.
    • Superscript can be denoted by <sup>text</sup> and subscript <sub>text</sub>.
    • Numbered or bulleted lists can be created using either numbered lines 1. 2. 3., hyphens - or asterisks *.
    • Links can be included with: [my link to pubmed](http://pubmed.com)
    • Images can be included with: ![alt text](https://bestmedicaljournal.com/study_graph.jpg "Image Title Text")
    • For footnotes use [^1](This is a footnote.) inline.
    • Or use an inline reference [^1] to refer to a longer footnote elseweher in the document [^1]: This is a long footnote..

    hide…