Given the emergence of transmissible strains of Pseudomonas aeruginosa, such as the Liverpool epidemic strain (LES), in cystic fibrosis (CF) centres, it is important to carry out regular surveillance of isolates. In a survey of 22 P. aeruginosa isolates, each from a different CF patient identified as negative for LES in a paediatric centre in Liverpool, six (23 %) were identified as being the same clone type (clone D) using array-tube genotyping. Using a series of alternative genotyping approaches [PFGE, random amplification of polymorphic DNA (RAPD), variable number of tandem repeats (VNTR) and multilocus sequence typing (MLST)], the six CF clone D isolates and eight previously identified clone D isolates associated with infections leading to keratitis were compared. All but two of the clone D isolates (both keratitis-associated) were assigned by MLST to sequence type 235 and were highly similar using VNTR analysis. However, there was considerable variation found among the isolates when using PFGE or RAPD, highlighting the limitations of these methods. The discordance with respect to two of the isolates identified by array-tube genotyping as clone D, when using all the other typing methods, emphasizes the need to use more than one method for reliable identification of strains.
AaronS. D., VandemheenK. L., RamotarK., Giesbrecht-LewisT., TullisE., FreitagA., PatersonN., JacksonM., LougheedM. D.& other authors (2010; Infection with transmissible strains of Pseudomonas aeruginosa and clinical outcomes in adults with cystic fibrosis. JAMA 304:2145–2153 [View Article][PubMed]
AroraS. K., BangeraM., LoryS., RamphalR.2001; A genomic island in Pseudomonas aeruginosa carries the determinants of flagellin glycosylation. Proc Natl Acad Sci U S A 98:9342–9347 [View Article][PubMed]
AshishA., ShawM., WinstanleyC., LedsonM. J., WalshawM. J.2012; Increasing resistance of the Liverpool Epidemic Strain (LES) of Pseudomonas aeruginosa (Psa) to antibiotics in cystic fibrosis (CF) – a cause for concern?. J Cyst Fibros 11:173–179 [View Article][PubMed]
CramerN., KlockgetherJ., WrasmanK., SchmidtM., DavenportC. F., TümmlerB.2011; Microevolution of the major common Pseudomonas aeruginosa clones C and PA14 in cystic fibrosis lungs. Environ Microbiol 13:1690–1704 [View Article][PubMed]
CurranB., JonasD., GrundmannH., PittT., DowsonC. G.2004; Development of a multilocus sequence typing scheme for the opportunistic pathogen Pseudomonas aeruginosa. J Clin Microbiol 42:5644–5649 [View Article][PubMed]
de ChialM., GhyselsB., BeatsonS. A., GeoffroyV., MeyerJ. M., PatteryT., BaysseC., ChablainP., ParsonsY. N.& other authors (2003; Identification of type II and type III pyoverdine receptors from Pseudomonas aeruginosa. Microbiology 149:821–831 [View Article][PubMed]
De VosD., LimA.Jr, PirnayJ. P., StruelensM., VandenveldeC., DuinslaegerL., VanderkelenA., CornelisP.1997; Direct detection and identification of Pseudomonas aeruginosa in clinical samples such as skin biopsy specimens and expectorations by multiplex PCR based on two outer membrane lipoprotein genes, oprI and oprL. J Clin Microbiol 35:1295–1299[PubMed]
FothergillJ. L., UptonA. L., PittT. L., HartC. A., WinstanleyC.2008; Diagnostic multiplex PCR assay for the identification of the Liverpool, Midlands 1 and Manchester CF epidemic strains of Pseudomonas aeruginosa. J Cyst Fibros 7:258–261 [View Article][PubMed]
FothergillJ. L., MowatE., LedsonM. J., WalshawM. J., WinstanleyC.2010a; Fluctuations in phenotypes and genotypes within populations of Pseudomonas aeruginosa in the cystic fibrosis lung during pulmonary exacerbations. J Med Microbiol 59:472–481 [View Article][PubMed]
GaillardE. A., WallaceH. L., HeafL. J., PanageaS., ShearsP., BurrowsE. F., GarnettP., CottrellJ. J., WalshawM. J.& other authors (2004; The Liverpool epidemic strain of Pseudomonas aeruginosa; 8 years after initial identification. J Cyst Fibros 3:S50
García-CastilloM., MáizL., MorosiniM. I., Rodríguez-BañosM., SuarezL., Fernández-OlmosA., BaqueroF., CantónR., del CampoR.2012; Emergence of a mutL mutation causing multilocus sequence typing-pulsed-field gel electrophoresis discrepancy among Pseudomonas aeruginosa isolates from a cystic fibrosis patient. J Clin Microbiol 50:1777–1778 [View Article][PubMed]
GovanJ. R. W., BrownA. R., JonesA. M.2007; Evolving epidemiology of Pseudomonas aeruginosa and the Burkholderia cepacia complex in cystic fibrosis lung infection. Future Microbiol 2:153–164 [View Article][PubMed]
HunterP. R., GastonM. A.1988; Numerical index of the discriminatory ability of typing systems: an application of Simpson’s index of diversity. J Clin Microbiol 26:2465–2466[PubMed]
JohnsonJ. K., ArduinoS. M., StineO. C., JohnsonJ. A., HarrisA. D.2007; Multilocus sequence typing compared to pulsed-field gel electrophoresis for molecular typing of Pseudomonas aeruginosa. J Clin Microbiol 45:3707–3712 [View Article][PubMed]
KiddT. J., GrimwoodK., RamsayK. A., RaineyP. B., BellS. C.2011; Comparison of three molecular techniques for typing Pseudomonas aeruginosa isolates in sputum samples from patients with cystic fibrosis. J Clin Microbiol 49:263–268 [View Article][PubMed]
KlockgetherJ., RevaO., LarbigK., TümmlerB.2004; Sequence analysis of the mobile genome island pKLC102 of Pseudomonas aeruginosa C. J Bacteriol 186:518–534 [View Article][PubMed]
LiangX., PhamX.-Q. T., OlsonM. V., LoryS.2001; Identification of a genomic island present in the majority of pathogenic isolates of Pseudomonas aeruginosa. J Bacteriol 183:843–853 [View Article][PubMed]
MaatallahM., CheriaaJ., BackhroufA., IversenA., GrundmannH., DoT., LanotteP., MastouriM., ElghmatiM. S.& other authors (2011; Population structure of Pseudomonas aeruginosa from five Mediterranean countries: evidence for frequent recombination and epidemic occurrence of CC235. PLoS ONE 6:e25617 [View Article][PubMed]
MahenthiralingamE., CampbellM. E., FosterJ., LamJ. S., SpeertD. P.1996; Random amplified polymorphic DNA typing of Pseudomonas aeruginosa isolates recovered from patients with cystic fibrosis. J Clin Microbiol 34:1129–1135[PubMed]
McCallumS. J., CorkillJ., GallagherM., LedsonM. J., HartC. A., WalshawM. J.2001; Superinfection with a transmissible strain of Pseudomonas aeruginosa in adults with cystic fibrosis chronically colonised by P aeruginosa. Lancet 358:558–560 [View Article][PubMed]
MoralesG., WiehlmannL., GudowiusP., van DeldenC., TümmlerB., MartínezJ. L., RojoF.2004; Structure of Pseudomonas aeruginosa populations analyzed by single nucleotide polymorphism and pulsed-field gel electrophoresis genotyping. J Bacteriol 186:4228–4237 [View Article][PubMed]
MowatE., PatersonS., FothergillJ. L., WrightE. A., LedsonM. J., WalshawM. J., BrockhurstM. A., WinstanleyC.2011; Pseudomonas aeruginosa population diversity and turnover in cystic fibrosis chronic infections. Am J Respir Crit Care Med 183:1674–1679 [View Article][PubMed]
MuraseT., YamaiS., WatanabeH.1999; Changes in pulsed-field gel electrophoresis patterns in clinical isolates of enterohemorrhagic Escherichia coli O157 : H7 associated with loss of Shiga toxin genes. Curr Microbiol 38:48–50 [View Article][PubMed]
OntenienteL., BrisseS., TassiosP. T., VergnaudG.2003; Evaluation of the polymorphisms associated with tandem repeats for Pseudomonas aeruginosa strain typing. J Clin Microbiol 41:4991–4997 [View Article][PubMed]
ParsonsY. N., PanageaS., SmartC. H. M., WalshawM. J., HartC. A., WinstanleyC.2002; Use of subtractive hybridization to identify a diagnostic probe for a cystic fibrosis epidemic strain of Pseudomonas aeruginosa. J Clin Microbiol 40:4607–4611 [View Article][PubMed]
RömlingU., SchmidtK. D., TümmlerB.1997; Large genome rearrangements discovered by the detailed analysis of 21 Pseudomonas aeruginosa clone C isolates found in environment and disease habitats. J Mol Biol 271:386–404 [View Article][PubMed]
SchmidtK. D., TümmlerB., RömlingU.1996; Comparative genome mapping of Pseudomonas aeruginosa PAO with P. aeruginosa C, which belongs to a major clone in cystic fibrosis patients and aquatic habitats. J Bacteriol 178:85–93[PubMed]
ScottF. W., PittT. L.2004; Identification and characterization of transmissible Pseudomonas aeruginosa strains in cystic fibrosis patients in England and Wales. J Med Microbiol 53:609–615 [View Article][PubMed]
SelezskaK., KazmierczakM., MüskenM., GarbeJ., SchobertM., HäusslerS., WiehlmannL., RohdeC., SikorskiJ.2012; Pseudomonas aeruginosa population structure revisited under environmental focus: impact of water quality and phage pressure. Environ Microbiol 14:1952–1967 [View Article][PubMed]
SmartC. H. M., WalshawM. J., HartC. A., WinstanleyC.2006; Use of suppression subtractive hybridization to examine the accessory genome of the Liverpool cystic fibrosis epidemic strain of Pseudomonas aeruginosa. J Med Microbiol 55:677–688 [View Article][PubMed]
StewartR. M. K., WiehlmannL., AshelfordK. E., PrestonS. J., FrimmersdorfE., CampbellB. J., NealT. J., HallN., TuftS.& other authors (2011; Genetic characterization indicates that a specific subpopulation of Pseudomonas aeruginosa is associated with keratitis infections. J Clin Microbiol 49:993–1003 [View Article][PubMed]
TurtonJ. F., TurtonS. E., YearwoodL., YardeS., KaufmannM. E., PittT. L.2010; Evaluation of a nine-locus variable-number tandem-repeat scheme for typing of Pseudomonas aeruginosa. Clin Microbiol Infect 16:1111–1116 [View Article][PubMed]
van MansfeldR., JongerdenI., BootsmaM., BuitingA., BontenM., WillemsR.2010; The population genetics of Pseudomonas aeruginosa isolates from different patient populations exhibits high-level host specificity. PLoS ONE 5:e13482 [View Article][PubMed]
WiehlmannL., WagnerG., CramerN., SiebertB., GudowiusP., MoralesG., KöhlerT., van DeldenC., WeinelC.& other authors (2007; Population structure of Pseudomonas aeruginosa. Proc Natl Acad Sci U S A 104:8101–8106 [View Article][PubMed]
WinstanleyC., LangilleM. G. I., FothergillJ. L., Kukavica-IbruljI., Paradis-BleauC., SanschagrinF., ThomsonN. R., WinsorG. L., QuailM. A.& other authors (2009; Newly introduced genomic prophage islands are critical determinants of in vivo competitiveness in the Liverpool Epidemic Strain of Pseudomonas aeruginosa. Genome Res 19:12–23 [View Article][PubMed]