Phenotypic and genotypic characterization of Staphylococci causing XXXX in oncologic patients.

@entity10283 @entity3256 @entity0 @entity5938 @entity794 @entity281 @entity413 @entity4202
BACKGROUND: @entity5938 and @entity794 have been identified as the most common bacteria responsible for sub-clinical and overt @entity0 and their ability to form biofilm on the implant as been reported as the essential factor in the development of this type of @entity281 . Biofilm formation is a complex process with the participation of several distinct molecules, whose relative importance in different clinical settings has not yet been fully elucidated. To our knowledge this is the first study aimed at characterizing isolates causing @entity0 . RESULTS: Thirteen @entity794 and seven @entity5938 causing @entity0 were studied. Using the broth microdilution method and the E-test, the majority of the strains were susceptible to all antibiotics tested. @entity3256 resistance was detected in two @entity5938 . All strains had different RAPD profiles and were able to produce biofilms in microtitre plate assays but, while all @entity794 carried and were able to express icaA and icaD genes, this was only true for one @entity5938 . Biofilm development was @entity413 - and @entity4202 -induced (5   @entity794 and 1   @entity5938 ) or @entity413 -induced (the remaining strains). Proteinase K and @entity10283 treatment had different effects on biofilms dispersion revealing that the strains studied were able to produce chemically different types of extracellular matrix mediating biofilm formation. All @entity794 strains harboured and expressed the atlA, clfA, FnA, eno and cna genes and the majority also carried and expressed the sasG (10/13), ebpS (10/13) genes. All @entity5938 strains harboured and expressed the atlE, aae, embp genes, and the majority (six strains) also carried and expressed the fbe, aap genes. Genes for @entity794 capsular types 5 and 8 were almost equally distributed. The only leukotoxin genes detected were lukE/lukD (6/13). CONCLUSIONS: @entity794 and @entity5938 @entity0 are caused by heterogeneous strains with different biofilm development mechanisms. Since the collagen adhesin (cna) gene is not ubiquitously distributed among @entity794 , this protein could have an important role in the cause of @entity0 .
