Hemolytic activity and biofilm-formation among clinical isolates of group B streptococcus causing acute urinary tract infection and asymptomatic bacteriuria

Streptococcus agalactiae, also known as group B Streptococcus, is an aetiological agent of urinary tract infection (UTI) in adults, including cystitis, pyelonephritis and asymptomatic bacteriuria (ABU). Whereas ABU-causing S. agalactiae (ABSA) have been shown to grow achieve higher culture denstity human urine compared uropathogenic (UPSA) other phenotypic distinctions between isolated from different forms UTI are not known. Here, we define the hemolytic activities biofilm-formation a collection clinical isolates UPSA, ABSA recurrent (rSAB) strains explore these phenotypes context history isolates. A total 61 184 ABSA, 47 rSAB were analyzed for relative activity by spot assay on blood agar, which was validated using erythrocyte lysis suspension assay. Biofilm formation determined microtiter plate with Lysogeny Todd-Hewitt broths supplemented 1% glucose induce biofilm formation. We used multiplex PCR analyze presence genes encoding adhesive pili, contribute Comparing 292 showed, surprisingly, that significantly more likely be highly strains. In contrast, there no differences abilities groups form biofilms. Taken together, findings demonstrate propensity causing ABU but link ability biofilm.