title: The first case report of infective endocarditis caused by Gemella taiwanensis.
abstract: Gemella is a facultative anaerobic Gram-positive coccus and a rare cause of infective endocarditis (IE). Gram staining may eventually misidentify the organism, which tends to easily decolorize and manifest as either Gram-negative or Gram-variable. Commercial biochemical tests are often used to identify Gemella, but the methods they employ sometimes lack accuracy. A 52-year-old woman was diagnosed with Gemella taiwanensis IE after initial identification of the pathogen as Gemella haemolysans using biochemical tests combined with matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). She was treated successfully with penicillin, gentamicin, and mitral valve replacement. To our knowledge, this is the first case of IE confirmed by 16S rRNA gene and groEL sequencing to have been caused by G. taiwanensis. The accurate diagnosis of rare or difficult-to-identify pathogens is a major challenge for clinical microbiological laboratories. The concurrent use of molecular methods could lead to the recognition of new or different pathogens.
authors.affiliation: Department of Infectious Diseases, Tokyo Metropolitan Bokutoh General Hospital, Tokyo, Japan. Electronic address: mayuhikone@nifty.com.
authors.forename: Mayu
authors.initials: M
authors.lastname: Hikone
authors.affiliation: Department of Infectious Diseases, Tokyo Metropolitan Bokutoh General Hospital, Tokyo, Japan.
authors.forename: Naoya
authors.initials: N
authors.lastname: Sakamoto
authors.affiliation: Department of Infectious Diseases, Tokyo Metropolitan Bokutoh General Hospital, Tokyo, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Ota
authors.affiliation: Department of Infectious Diseases, Tokyo Metropolitan Bokutoh General Hospital, Tokyo, Japan.
authors.forename: Takuya
authors.initials: T
authors.lastname: Washino
authors.affiliation: Department of Infectious Diseases, Tokyo Metropolitan Bokutoh General Hospital, Tokyo, Japan.
authors.forename: Ken-Ichiro
authors.initials: KI
authors.lastname: Kobayashi
authors.affiliation: Department of Infectious Diseases, Tokyo Metropolitan Bokutoh General Hospital, Tokyo, Japan.
authors.forename: Sentaro
authors.initials: S
authors.lastname: Iwabuchi
authors.affiliation: Department of Clinical Laboratory, Tokyo Metropolitan Bokutoh General Hospital, Tokyo, Japan.
authors.forename: Haruko
authors.initials: H
authors.lastname: Kazama
authors.affiliation: Department of Clinical Laboratory, Tokyo Metropolitan Bokutoh General Hospital, Tokyo, Japan.
authors.forename: Akiko
authors.initials: A
authors.lastname: Kounosu
authors.affiliation: Department of Clinical Laboratory, Tokyo Metropolitan Bokutoh General Hospital, Tokyo, Japan.
authors.forename: Kumiko
authors.initials: K
authors.lastname: Negishi
authors.affiliation: Department of Infectious Diseases, Tokyo Women's Medical University, Tokyo, Japan; Department of Infectious Diseases, Tokyo Metropolitan Health and Medical Corporation Ebara Hospital, Tokyo, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Ainoda
authors.affiliation: Department of Infectious Diseases, Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: Shigekazu
authors.initials: S
authors.lastname: Iguchi
authors.affiliation: Department of Infectious Diseases, Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Yoshida
authors.affiliation: Department of Infectious Diseases, Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Kikuchi
authors.affiliation: Department of Infectious Diseases, Tokyo Metropolitan Health and Medical Corporation Ebara Hospital, Tokyo, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Ohnishi
mesh_terms: D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D001426:Bacterial Proteins / Q000235:genetics; D018834:Chaperonin 60 / Q000235:genetics; D004269:DNA, Bacterial / Q000032:analysis / Q000235:genetics; D004697:Endocarditis, Bacterial / Q000175:diagnosis / Q000188:drug therapy / Q000382:microbiology; D005260:Female; D058834:Gemella / Q000145:classification / Q000235:genetics; D016908:Gram-Positive Bacterial Infections / Q000175:diagnosis / Q000188:drug therapy / Q000382:microbiology; D006801:Humans; D008875:Middle Aged; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D018834:Chaperonin 60; D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S
keywords: 16S rRNA gene sequencing; Gemella taiwanensis; Infective endocarditis; groEL sequencing