Globicatella sanguinis osteomyelitis and bacteremia: Review of an emerging human pathogen with an expanding spectrum of disease

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.