title: Value of multiplex PCR to determine the bacterial and viral aetiology of pneumonia in school-age children.
abstract: BACKGROUND
  Conventional methods for the aetiological diagnosis of community-acquired pneumonia (CAP) are often insufficient owing to low sensitivity and the long wait for the results of culture and particularly serology, and it often these methods establish a diagnosis in only half of cases.
  
  
  OBJECTIVE
  To evaluate the most common bacterial and viral agents in CAP using a fast responsive PCR method and investigate the relationship between clinical/laboratory features and aetiology, thereby contributing to empirical antibiotic selection and reduction of treatment failure.
  
  
  METHODS
  In children aged 4-15 years consecutively admitted with a diagnosis of CAP, the 10 most commonly detected bacterial and 12 most commonly detected viral agents were investigated by induced sputum using bacterial culture and multiplex PCR methods. Clinical and laboratory features were compared between bacterial and viral pneumonia.
  
  
  RESULTS
  In 78 patients, at least one virus was detected in 38 (48.7%) and at least one bacterium in 32 (41%). In addition, both bacteria and viruses were detected in 16 (20.5%) patients. Overall, the agent detection rate was 69.2%. The most common viruses were respiratory syncytial virus and influenza and the most frequently detected bacteria were S. pneumoniae and H. influenzae. PCR was superior to culture for bacterial isolation (41% vs 13%, respectively). Fever, wheezing and radiological features were not helpful in differentiating between bacterial and viral CAP. White blood cell count, CRP and ESR values were significantly higher in the bacterial/mixed aetiology group than in the viral aetiology group.
  
  
  CONCLUSIONS
  In CAP, multiplex PCR is highly reliable, superior in detecting multiple pathogens and rapidly identifies aetiological agents. Clinical features are poor for differentiation between bacterial and viral infections. The use of PCR methods allow physicians to provide more appropriate antimicrobial therapy, resulting in a better response to treatment, and it may be possible for use as a routine service if costs can be reduced.
authors.affiliation: a Departments of Pulmonology , Sakarya University , Sakarya.
authors.forename: Yusuf
authors.initials: Y
authors.lastname: Aydemir
authors.affiliation: b Departments of Microbiology , Sakarya University , Sakarya , Turkey.
authors.forename: Özlem
authors.initials: Ö
authors.lastname: Aydemir
authors.affiliation: c Departments of Pediatric Pulmonology , Necmettin Erbakan University , Konya , Turkey.
authors.forename: Sevgi
authors.initials: S
authors.lastname: Pekcan
authors.affiliation: d Departments of Microbiology , Necmettin Erbakan University , Konya , Turkey.
authors.forename: Mehmet
authors.initials: M
authors.lastname: Özdemir
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D017714:Community-Acquired Infections / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008297:Male; D025202:Molecular Diagnostic Techniques / Q000379:methods*; D060885:Multiplex Polymerase Chain Reaction / Q000379:methods*; D018410:Pneumonia, Bacterial / Q000175:diagnosis*; D011024:Pneumonia, Viral / Q000175:diagnosis*
keywords: Clinical features; Laboratory features; PCR; Pneumonia