title: Clinical relevance of Corynebacterium pseudodiphtheriticum in lower respiratory tract specimens.
abstract: BACKGROUND
  Corynebacterium pseudodiphtheriticum may be present as commensal flora of the respiratory tract and therefore it may be difficult to assess clinical relevance when it is cultured from lower respiratory tract specimens. Our objective was to determine the clinical relevance of C. pseudodiphtheriticum as a lower respiratory tract pathogen and to define patients at risk of developing lower respiratory tract infections caused by C. pseudodiphtheriticum.
  
  
  METHODS
  We retrospectively identified all lower respiratory tract cultures positive for C. pseudodiphtheriticum over a 10-year period and assessed clinical relevance by predefined criteria.
  
  
  RESULTS
  Clinical relevance was likely or possible in 86% of patients. Pre-existent comorbidity was present in 86% of patients, mostly underlying cardiac or pulmonary disease. All isolates were susceptible to amoxicillin.
  
  
  CONCLUSIONS
  C. pseudodiphtheriticum should be considered a clinically relevant pathogen when cultured from the lower respiratory tract in symptomatic patients.
authors.affiliation: a From the Department of Internal Medicine , Diakonessenhuis Utrecht , The Netherlands.
authors.forename: Sonja E
authors.initials: SE
authors.lastname: Van Roeden
authors.affiliation: b Department of Medical Microbiology and Immunology , Diakonessenhuis Utrecht , The Netherlands.
authors.forename: Steven F
authors.initials: SF
authors.lastname: Thijsen
authors.affiliation: a From the Department of Internal Medicine , Diakonessenhuis Utrecht , The Netherlands.
authors.forename: Sanjay U C
authors.initials: SU
authors.lastname: Sankatsing
authors.affiliation: c Department of Pulmonary Diseases , Diakonessenhuis Utrecht , The Netherlands.
authors.forename: Gijs J M
authors.initials: GJ
authors.lastname: Limonard
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000658:Amoxicillin / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001992:Bronchoalveolar Lavage Fluid / Q000382:microbiology; D003352:Corynebacterium / Q000187:drug effects / Q000302:isolation & purification* / Q000472:pathogenicity; D003354:Corynebacterium Infections / Q000382:microbiology*; D005260:Female; D006331:Heart Diseases / Q000150:complications; D006801:Humans; D008171:Lung Diseases / Q000150:complications; D008297:Male; D008875:Middle Aged; D010996:Pleural Effusion / Q000382:microbiology; D011014:Pneumonia / Q000382:microbiology; D012141:Respiratory Tract Infections / Q000382:microbiology*; D012189:Retrospective Studies; D012307:Risk Factors; D013183:Sputum / Q000382:microbiology; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents; D000658:Amoxicillin
keywords: Corynebacterium pseudodiphtheriticum; Corynebacterium species; lower respiratory tract infections; pneumonia; respiratory infections