Dataset Information

Assessing the diagnostic accuracy of PCR-based detection of Streptococcus pneumoniae from nasopharyngeal swabs collected for viral studies in Canadian adults hospitalised with community-acquired pneumonia: a Serious Outcomes Surveillance (SOS) Network of the Canadian Immunization Research (CIRN) study.

ABSTRACT:

Study design

Detection and serotyping of Streptococcus pneumoniae are important to assess the impact of pneumococcal vaccines. This study describes the diagnostic accuracy of PCR-based detection of S. pneumoniae directly from nasopharyngeal (NP) swabs collected for respiratory virus studies.

Methods

Active surveillance for community-acquired pneumonia (CAP) in hospitalised adults was performed from December 2010 to 2013. Detection of pneumococcal CAP (CAP_Spn) was performed by urine antigen detection (UAD), identification of S. pneumoniae in sputum or blood cultures. S. pneumoniae was detected in NP swabs using lytA and cpsA real-time PCR, and serotyping was performed using conventional and real-time multiplex PCRs. For serotyping, the Quellung reaction, PCR-based serotyping or a serotype-specific UAD was used.

Results

NP swab results were compared against CAP cases where all pneumococcal tests were performed (n=434), or where at least one test was performed (n=1616). CAP_Spn was identified in 22.1% (96/434) and 14.9% (240/1616), respectively. The sensitivity of NP swab PCR for the detection of S. pneumoniae was poor for CAP_Spn (35.4% (34/96) and 34.17% (82/240)), but high specificity was observed (99.4% (336/338) and 97.89% (1347/1376)). Of the positive NP swabs, a serotype could be deduced by PCR in 88.2% (30/34) and 93.9% (77/82), respectively.

Conclusions

While further optimisation may be needed to increase the sensitivity of PCR-based detection, its high specificity suggests there is a value for pneumococcal surveillance. With many laboratories archiving specimens for influenza virus surveillance, this specimen type could provide a non-culture-based method for pneumococcal surveillance.

SUBMITTER: Gillis HD

PROVIDER: S-EPMC5623389 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Publications

Assessing the diagnostic accuracy of PCR-based detection of <i>Streptococcus pneumoniae</i> from nasopharyngeal swabs collected for viral studies in Canadian adults hospitalised with community-acquired pneumonia: a Serious Outcomes Surveillance (SOS) Network of the Canadian Immunization Research (CIRN) study.

Gillis Hayley D HD Lang Amanda L S ALS ElSherif May M Martin Irene I Hatchette Todd F TF McNeil Shelly A SA LeBlanc Jason J JJ

BMJ open 20170608 6

<h4>Study design</h4>Detection and serotyping of <i>Streptococcus pneumoniae are</i> important to assess the impact of pneumococcal vaccines. This study describes the diagnostic accuracy of PCR-based detection of <i>S. pneumoniae</i> directly from nasopharyngeal (NP) swabs collected for respiratory virus studies.<h4>Methods</h4>Active surveillance for community-acquired pneumonia (CAP) in hospitalised adults was performed from December 2010 to 2013. Detection of pneumococcal CAP (CAP<sub>Spn</su ...[more]

PMID: 28600368

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