Search

A 1-month old neonate urine sample yielded vanB Enterococcus faecium; nevertheless, the isolate alternatively showed susceptibility and resistance to vancomycin with bioMérieux Vitek2 (cards AST592, AST632, AST586), while glycopeptide resistance was detected by Liofilchem(®) vancomycin MIC Test Strip and disc along with the Chromatic VRE chromogenic medium. This communication emphasizes that, as vanB gene may be heterogeneously expressed within a given Enterococcus population, glycopeptide resistance may be missed when using automated systems for antibiotic susceptibility testing. We suggest therefore that vancomycin in vitro activity be studied on all clinical isolates through agar methods, including use of chromogenic media.

We report the case of a late-onset neonatal meningitis by Streptococcus agalactiae (group B Streptococcus - GBS) that was diagnosed with a latex agglutination assay (on cerebrospinal fluid, CSF), as well as by using, for the first time, Xpert GBS (Cepheid, US) on CSF. Due to empirical antibiotics given before sampling, both CSF and blood culture were negative, so the abovementioned diagnostics was crucial. Moreover, the Xpert GBS assay, performed according to an off-label, modified protocol (the system is designed for GBS-carriage intrapartum screening, based on a completely automated real time-Polymerase Chain Reaction) quickly detected the organism's genome target. Although further investigation on this test's performace on CSF is required, then, we trust it may be a promising, quick and precise diagnostic method for infections in newborns.