Direct Streptococcus pneumoniae real-time PCR serotyping from pediatric parapneumonic effusions

BMC Pediatr. 2014 Jul 24;14:189. doi: 10.1186/1471-2431-14-189.


Background: To determine the serotypes of Streptococcus pneumoniae responsible for pneumonia complicated by parapneumonic effusion in children, we performed real-time PCR based pneumococcal "serotyping" directly on parapneumonic fluid samples.

Methods: Specimens were collected at two children's hospitals in Ontario, Canada from 2009 to 2011. Samples in which S. pneumoniae was detected by PCR were tested with serotype-specific 5'exonuclease PCR assays for the 13 serotypes contained in the 13-serotype pneumococcal vaccine.

Results: Thirty-five S. pneumoniae PCR-positive pleural samples were studied. Pneumococcal serotyping PCR assays were positive for 34 of 35 (97%). Serotype 3 was detected most frequently, in 19/35 (54%), followed by serotype 19A in 9/35 (26%), serotype 7 F/A in 4/35 (11%), serotype 1 in 1/35 (3%), and serotype 6A also in 1/35 (3%).

Conclusions: PCR testing demonstrated that the vast majority (97%) of S. pneumoniae parapneumonic effusions were caused by serotypes present in the 13-serotype vaccine that were not present in the original 7 serotype vaccine. This suggests that use of the 13-serotype vaccine could potentially prevent many S. pneumoniae pneumonias complicated by parapneumonic effusion in our region, provided serotype replacement does not occur.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Empyema, Pleural / microbiology
  • Humans
  • Ontario
  • Pleural Effusion / microbiology*
  • Pneumococcal Vaccines
  • Pneumonia, Pneumococcal / complications*
  • Pneumonia, Pneumococcal / microbiology
  • Real-Time Polymerase Chain Reaction
  • Serotyping
  • Streptococcus pneumoniae / classification*
  • Streptococcus pneumoniae / isolation & purification


  • Pneumococcal Vaccines