Weissella confusa: an unexpected cause of vancomycin-resistant gram-positive bacteremia in immunocompromised hosts

摘要: We report the first case of Weissella confusa bacteremia in an allogeneic hematopoietic stem cell transplant patient. After engraftment and discharge, patient returned with fever graft failure was started on empiric regimen aztreonam vancomycin. A blood culture grew alpha-hemolytic, gram-positive coccus forming pairs chains, originally thought to be a viridans Streptococcus skin contaminant. The isolation organism from multiple cultures, presence vancomycin resistance prompted identification additional susceptibility testing. RapID(™) Str panel, which has W. its database, provided incorrect identifications. MicroScan WalkAway 96 SI, using PC-20 or -29 panels, also did not identify this bacterium, because it is their database. identified as by 16S rDNA sequencing. Antibiotic determination Etest revealed daptomycin susceptibility. Therapy changed daptomycin, infection resolved. Additionally, sepsis, positive developed burn unit at our medical center. patient's cultures remained until discontinued therapy initiated. Infections vancomycin-resistant, cocci are emerging among immuno compromised hosts. Under appropriate circumstances, clinicians need request that laboratory perform testing accurate identification, nucleic acid sequencing if necessary. Sequencing important tool unusual pathogens.