title: Clinical and bacteriological analyses of bacteremia due to Corynebacterium striatum.
abstract: BACKGROUND
  Corynebacterium striatum was recently recognized as a potential pathogen of various infectious diseases. However, the clinical entity of this microorganism has not been clearly identified. Therefore, we analyzed C. striatum isolates from blood culture and explored their clinical determinants.
  
  
  METHODS
  We reviewed the medical records of all patients from whom C. striatum isolates were recovered from blood culture for analysis of the patients' backgrounds and clinical course including response to antimicrobial therapy and prognosis.
  
  
  RESULTS
  During the 5-year study period (January 2010 to December 2014), 24 C. striatum strains were isolated from blood samples, and the frequency of C. striatum bacteremia increased. The majority of the strains were multidrug resistant. All of the tested strains were susceptible to only vancomycin. The age at onset of C. striatum bacteremia encompassed all adult age groups, and at least one underlying condition was documented in all patients. Thirteen of the 24 patients were cured using appropriate antibiotics (true infection group); however, 11 of the 24 patients were cured using inappropriate antibiotic therapy or no antibiotics (contamination group). Malignancy and neutropenia significantly increased the odds of true C. striatum bloodstream infection.
  
  
  CONCLUSIONS
  The Corynebacterium species is often considered a contaminant when isolated in culture. Instead, particularly when the strain is isolated from blood, the species should be considered clinically relevant and identified to the species level; in addition, antimicrobial susceptibility testing is recommended.
authors.affiliation: Department of Infectious Diseases, Medical Mycology Research Center, Chiba University, Chiba, Japan. Electronic address: ishiwada@faculty.chiba-u.jp.
authors.forename: Naruhiko
authors.initials: N
authors.lastname: Ishiwada
authors.affiliation: Division of Clinical Laboratory, Chiba University Hospital, Chiba, Japan.
authors.forename: Masaharu
authors.initials: M
authors.lastname: Watanabe
authors.affiliation: Division of Clinical Laboratory, Chiba University Hospital, Chiba, Japan.
authors.forename: Shota
authors.initials: S
authors.lastname: Murata
authors.affiliation: Department of Infectious Diseases, Medical Mycology Research Center, Chiba University, Chiba, Japan.
authors.forename: Noriko
authors.initials: N
authors.lastname: Takeuchi
authors.affiliation: Department of Infectious Diseases, Chiba University Hospital, Chiba, Japan.
authors.forename: Toshibumi
authors.initials: T
authors.lastname: Taniguchi
authors.affiliation: Department of Infectious Diseases, Chiba University Hospital, Chiba, Japan.
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Igari
mesh_terms: D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D016470:Bacteremia / Q000188:drug therapy / Q000382:microbiology*; D003352:Corynebacterium / Q000187:drug effects / Q000302:isolation & purification*; D003354:Corynebacterium Infections / Q000188:drug therapy / Q000382:microbiology*; D024901:Drug Resistance, Multiple, Bacterial / Q000187:drug effects; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D014640:Vancomycin / Q000627:therapeutic use
chemical_list: D000900:Anti-Bacterial Agents; D014640:Vancomycin
keywords: Antibiotics; Bacteremia; Contamination; Corynebacterium striatum; Multidrug resistance