title: Bordetella pertussis and mixed infections.
abstract: OBJECTIVE
  In pertussis-like respiratory infections, once pertussis has been laboratory confirmed, other potential causative pathogens will seldom be looked for. Probably most mixed infections are found accidentally and since these mixed infections might cause a more severe disease we performed a retrospective study of their incidence.
  
  
  METHODS
  We selected from 2 groups of patients with serologically confirmed Bordetella (B.) pertussis infection those in whom serology for other respiratory pathogens had also been performed. Group 1 consisted of 50 pertussis patients with 51 episodes of B. pertussis infection selected from 100 patients with serologically confirmed pertussis. They participated in a long-term follow-up after a B. pertussis infection. In group 2, 31 pertussis patients were selected from 98 consecutive patients with positive pertussis serology from one routine practice.
  
  
  RESULTS
  In 23 of 82 pertussis infections (28%) serological evidence of 1 (n = 21) or 2 (n = 2) additional infections were demonstrated. These involved para-influenza virus (n = 6), respiratory syncytial virus (RSV) (n = 6), Mycoplasma pneumoniae (n = 5), adenovirus (n = 4), influenza A virus (n = 3) and influenza B virus (n = 1).
  
  
  CONCLUSIONS
  We conclude that in patients with B. pertussis infection, coinfection with another respiratory pathogen is often present.
authors.affiliation: Department of Pediatrics, Groene Hart Ziekenhuis, Gouda, The Netherlands. versteegh@linuxmail.org
authors.forename: F G A
authors.initials: FG
authors.lastname: Versteegh
authors.forename: E A N M
authors.initials: EA
authors.lastname: Mooi-Kokenberg
authors.forename: J F P
authors.initials: JF
authors.lastname: Schellekens
authors.forename: J J
authors.initials: JJ
authors.lastname: Roord
mesh_terms: D001885:Bordetella Infections / Q000276:immunology / Q000382:microbiology*; D001886:Bordetella pertussis / Q000276:immunology / Q000472:pathogenicity*; D002648:Child; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology; D007075:Immunoglobulin M / Q000276:immunology; D008297:Male; D009175:Mycoplasma Infections / Q000453:epidemiology; D018184:Paramyxoviridae Infections / Q000382:microbiology; D018357:Respiratory Syncytial Virus Infections / Q000382:microbiology; D012189:Retrospective Studies; D014917:Whooping Cough / Q000276:immunology / Q000382:microbiology*
chemical_list: D007074:Immunoglobulin G; D007075:Immunoglobulin M