Project description:Globicatella sanguinis is a rare cause of acute meningitis. We demonstrated human carriage of Globicatella by identifying cefotaxime-resistant strains in groin and rectal specimens 9 months after invasive infection. The pathogenic strain isolated from the cerebrospinal fluid and the carriage strains were accurately identified by sodA gene sequence analysis.
Project description:BACKGROUND: Globicatella are streptococcus-like organisms that have been rarely isolated from clinical specimens. Their epidemiology and clinical significance remain largely unknown. AIMS: To describe two cases of Globicatella bacteraemia identified by 16S ribosomal RNA (rRNA) gene sequencing. METHODS: Two unidentified streptococcus-like bacteria isolated from blood cultures of patients were subject to 16S rRNA gene sequencing. RESULTS: Two cases of Globicatella bacteraemia were identified by 16S rRNA gene sequencing. In the first case, a gram positive coccus was isolated from the blood culture of an 80 year old woman with diabetes mellitus and nosocomial sepsis, who died the day after developing the bacteraemia. The bacterium was unidentified by conventional phenotypic tests, the Vitek (gram positive identification) and the ATB expression (ID32 Strep) systems. In the second case, a similar bacterium was isolated from the blood culture of a 92 year old woman with polymicrobial acute pyelonephritis complicated by septic shock, who subsequently recovered after antibiotic treatment. 16S rRNA gene sequencing of the two isolates showed 0.5% nucleotide difference from that of G. sulfidifaciens and 0.7% nucleotide difference from that of G. sanguinis, indicating that they were Globicatella species. CONCLUSIONS: Because Globicatella is rarely encountered in clinical microbiology laboratories, it may have been overlooked or misidentified in these cases. 16S rRNA gene sequencing is a useful tool to better characterise the epidemiology and clinical significance of Globicatella.
Project description:BACKGROUND:Globicatella sanguinis is an uncommon pathogen that may be misdiagnosed as viridans group streptococci. We review the literature of Globicatella and report 2 clinical cases in which catalase-negative Gram-positive cocci resembling viridans group streptococci with elevated minimum inhibitory concentrations (MICs) to ceftriaxone were inconsistently identified phenotypically, with further molecular characterization and ultimate identification of G sanguinis. METHODS:Two clinical strains (from 2 obese women; 1 with a prosthetic hip infection and the other with bacteremia) were analyzed with standard identification methods, followed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry, 16S recombinant ribonucleic acid (rRNA), and sodA polymerase chain reaction (PCR). The existing medical literature on Globicatella also was reviewed. RESULTS:Standard phenotypic methods failed to consistently identify the isolates. 16S PCR yielded sequences that confirmed Globicatella species. sodA sequencing provided species-level identification of G sanguinis. The review of literature reveals G sanguinis as an increasingly reported cause of infections of the urine, meninges, and blood. To our knowledge, this is the first reported case of an orthopedic infection caused by Globicatella sanguinis. A review of the 37 known cases of G sanguinis infection revealed that 83% of patients are female, and 89% are at the extremes of age (<5 or >65 years). CONCLUSIONS:Globicatella sanguinis, an uncommon pathogen with elevated minimum inhibitory concentrations to third-generation cephalosporins, is difficult to identify by phenotypic methods and typically causes infections in females at the extremes of age. It may colonize skin or mucosal surfaces. Advanced molecular techniques utilizing 16S rRNA with sodA PCR accurately identify G sanguinis.
Project description:Globicatella sanguinis is a very rare isolate in clinical samples. We present a case of meningitis in a 69-year-old female patient after implantation of an external left ventricular drainage due to a hydrocephalus. She recovered after antibiotic treatment with ceftriaxone.
Project description:Aerococcus urinae (Au) and Globicatella sanguinis (Gs) are gram-positive bacteria belonging to the family Aerococcaceae and colonize the human immunocompromised and catheterized urinary tract. We identified both pathogens in polymicrobial urethral catheter biofilms (CBs) with a combination of 16S rDNA sequencing, proteomic analyses, and microbial cultures. Longitudinal sampling of biofilms from serially replaced catheters revealed that each species persisted in the urinary tract of a patient in cohabitation with 1 or more gram-negative uropathogens. The Gs and Au proteomes revealed active glycolytic, heterolactic fermentation, and peptide catabolic energy metabolism pathways in an anaerobic milieu. A few phosphotransferase system (PTS)-based sugar uptake and oligopeptide ABC transport systems were highly expressed, indicating adaptations to the supply of nutrients in urine and from exfoliating squamous epithelial and urothelial cells. Differences in the Au vs Gs metabolisms pertained to citrate lyase and utilization and storage of glycogen (evident only in Gs proteomes) and to the enzyme Xfp that degrades d-xylulose-5'-phosphate and the biosynthetic pathways for 2 protein cofactors, pyridoxal 6'-phosphate and 4'-phosphopantothenate (expressed only in Au proteomes). A predicted ZnuA-like transition metal ion uptake system was identified for Gs while Au expressed 2 LPXTG-anchored surface proteins, one of which had a predicted pilin D adhesion motif. While these proteins may contribute to fitness and virulence in the human host, it cannot be ruled out that Au and Gs fill a niche in polymicrobial biofilms without being the direct cause of injury in urothelial tissues.
Project description:Both Aerococcus urinae (Au) and Globicatella sanguinis (Gs) colonize the human urinary tract and are in the Aerococcaceae family. These rarely pathogenic Gram-positive bacteria were identified in polymicrobial urethral catheter biofilms (CBs) using 16S rDNA and proteomic analyses in this study. For confirming the identities, Au and Gs strains were isolated from small blood agar colonies derived from the CB extracts. Longitudinal surveys of clinical urine specimens revealed their persistence in the urinary tract and recolonization of newly replaced catheters. Dominant CB cohabitating organisms were Enterobacteriaceae, especially Proteus mirabilis and Escherichia coli. The proteomes of Gs and Au profiled from the in vivo milieu suggest that their energy metabolisms rely on glycolytic, heterolactic fermentation and peptide catabolic pathways. Several PTS sugar uptake and oligopeptide ABC transport systems were also highly abundant in the in vivo proteomes of Au and Gs, indicative to adaptations to nutrients available in urine and exfoliated urothelial cells (protein and proteoglycan breakdown products). Differences in Au and Gs metabolisms pertained to citrate lyase and glycogen (only in the Gs proteome), use of Xfp to degrade D-xylulose-5â€™-phosphate, and synthesis pathways for enzyme cofactors pyridoxal 6â€™-phosphate and 4â€™-phosphopantothenate (the latter only in the Au proteome). Interestingly, predicted metal ion (ZnuA-like) uptake systems were abundant in Gs but not in Au in vivo. Au expressed two LPXTG-anchored surface proteins, one predicted to have a pilin D adhesion motif. We describe how two microorganisms not previously characterized metabolically adapt to the milieu in the catheterized human urinary tract. Whether they are true pathogens or bystanders in CBs needs further investigation.