MOLECULAR-IDENTIFICATION OF GEMELLA SPECIES FROM 3 PATIENTS WITH ENDOCARDITIS

Gemella morbillorum and Gemella haemolysans are opportunistic pathogen s which cause endocarditis and other severe infections. We report on t hree patients with endocarditis, one with endocarditis caused by G. ha emolysans and two with endocarditis caused by G. morbillorum. The pauc ity of reports concerning these bacteria is probably related to the di fficulties associated with their identification. For example, one of t he strains reported in this study was originally sent to our laborator y with a preliminary characterization as a short ''gram-negative'' coc cobacillus, highlighting the specific problem associated with Gram sta ining of these bacteria. The usefulness of 16S rRNA gene amplification , partial sequencing, and comparison of the nucleotide sequence to tho se in databases when standard phenotypic identification schemes are no t helpful is emphasized, We also suggest that the use of simple tests, such as testing susceptibility to vancomycin for gram-negative bacter ia and colistin for gram-positive bacteria, could prevent misinterpret ation of Gram staining in gram-variable bacteria such as Gemella spp.