Enhanced discrimination of highly clonal ST22-methicillin-resistant Staphylococcus aureus IV isolates achieved by combining spa, dru, and pulsed-field gel electrophoresis typing data.
Shore, Anna C Rossney, Angela S Kinnevey, Peter M Brennan, Orla M Creamer, Eilish Sherlock, Orla Dolan, Anthony Cunney, Robert Sullivan, Derek J Goering, Richard V
Shore, Anna C
Rossney, Angela S
Kinnevey, Peter M
Brennan, Orla M
Creamer, Eilish
Sherlock, Orla
Dolan, Anthony
Cunney, Robert
Sullivan, Derek J
Goering, Richard V
Advisors
Editors
Other Contributors
Date
2010-05
Date Submitted
Keywords
Other Subjects
Subject Mesh
Bacterial Typing Techniques
Cluster Analysis
DNA Fingerprinting
DNA, Bacterial
Electrophoresis, Gel, Pulsed-Field
Genotype
Humans
Ireland
Methicillin-Resistant Staphylococcus aureus
Microbial Sensitivity Tests
Sensitivity and Specificity
Sequence Analysis, DNA
Staphylococcal Infections
Staphylococcal Protein A
Cluster Analysis
DNA Fingerprinting
DNA, Bacterial
Electrophoresis, Gel, Pulsed-Field
Genotype
Humans
Ireland
Methicillin-Resistant Staphylococcus aureus
Microbial Sensitivity Tests
Sensitivity and Specificity
Sequence Analysis, DNA
Staphylococcal Infections
Staphylococcal Protein A
Planned Date
Start Date
Collaborators
Principal Investigators
Alternative Titles
Publisher
Abstract
ST22-methicillin-resistant Staphylococcus aureus type IV (ST22-MRSA-IV) is endemic in Irish hospitals and is designated antibiogram-resistogram type-pulsed-field group (AR-PFG) 06-01. Isolates of this highly clonal strain exhibit limited numbers of pulsed-field gel electrophoresis (PFGE) patterns and spa types. This study investigated whether combining PFGE and spa typing with DNA sequencing of the staphylococcal cassette chromosome mec element (SCCmec)-associated direct repeat unit (dru typing) would improve isolate discrimination. A total of 173 MRSA isolates recovered in one Irish hospital during periods in 2007 and 2008 were investigated using antibiogram-resistogram (AR), PFGE, spa, dru, and SCCmec typing. Isolates representative of each of the 17 pulsed-field group 01 (PFG-01) spa types identified underwent multilocus sequence typing, and all isolates were ST22. Ninety-seven percent of isolates (168 of 173) exhibited AR-PFG 06-01 or closely related AR patterns, and 163 of these isolates harbored SCCmec type IVh. The combination of PFGE, spa, and dru typing methods significantly improved discrimination of the 168 PFG-01 isolates, yielding 65 type combinations with a Simpson's index of diversity (SID) of 96.53, compared to (i) pairwise combinations of spa and dru typing, spa and PFGE typing, and dru and PFGE typing, which yielded 37, 44, and 43 type combinations with SIDs of 90.84, 91.00, and 93.57, respectively, or (ii) individual spa, dru, and PFGE typing methods, which yielded 17, 17, and 21 types with SIDs of 66.9, 77.83, and 81.34, respectively. Analysis of epidemiological information for a subset of PFG-01 isolates validated the relationships inferred using combined PFGE, spa, and dru typing data. This approach significantly enhances discrimination of ST22-MRSA-IV isolates and could be applied to epidemiological investigations of other highly clonal MRSA strains.
Language
en
ISSN
1098-660X
eISSN
ISBN
DOI
10.1128/JCM.02155-09
PMID
20335411