Antimicrobial susceptibility patterns and genomic diversity in strains of XXXX isolated in 1978-1997 in different Brazilian cities.

@entity1 @entity114 @entity7660 @entity4195 @entity803
@entity114 has been the antimicrobial of choice for the treatment of @entity4195 infections for almost six decades. Although @entity114 -resistant isolates have not been described to date, clinical failures have been reported after treatment with @entity7660 . In this study, we analysed the antimicrobial susceptibility and genetic diversity of @entity4195 isolates obtained from healthy carriers or @entity1 in different cities in the south and south east of Brazil. The MICs were determined for @entity114 and seven other antimicrobials. @entity114 tolerance was also investigated. Genetic diversity was analysed by PFGE after SmaI fragmentation of the genomic DNA. All 211 isolates tested were susceptible to @entity114 (MIC 0.0025-0.02 mg l(-1)). Four isolates were moderately @entity114 -tolerant (MBC/MIC = 16 mg l(-1)). Most of the other drugs tested were very active against the strains examined, except for @entity803 , to which 50 % of strains were resistant. We also found extensive genetic diversity, in that 60 different patterns were recognized in the 96 strains studied. Indeed, we found no correlation between @entity803 resistance and clonality. Despite this diversity, some PFGE patterns persisted for up to 18 years and specific clone types were spread over different geographical locations
