Detection of Chlaymidia Pneumoniae and Streptococcus Pneumoniae in Endodontic Infections

Methods: Specimens were aseptically obtained from teeth with endodontic infections in 23 different patients, who did not have antibiotics in the preceding month, and were otherwise healthy. DNAs were extracted using the QIA Amp DNA mini kit. For the detection of C. pneumoniae, PCR was carried out both in a single step format targeting 16SrRNA gene and as nested PCR with primers targeting the aromatic amino acid hydroxylase, in order to avoid problems related to sensitivity and specificity. S. pneumoniae, primers targeting 16SrRNA gene were used.

Results: The nested PCR reaction for the detection of C.pneumoniae showed an increased sensitivity (0.025fg) compared to the 16SrRNA PCR (25fg) and did not cross react with related species such C.trachomatis and C.pistacci. For S.pneumoniae, the primers were sensitive up to 10fg of genomic DNA of this organism, but cross reacted with DNA from several other Streptococcus spp., thus direct sequencing of the product was performed. C. pneumoniae could not be detected in any of the specimens tested with either method. The Streptococcus-specific reactions showed positive amplification in all but 3 specimens. Direct sequencing of the products did not reveal the presence of S. pneumoniae.

Conclusions: It is concluded that both C. pneumoniae and S. pneumonia do not appear to be common pathogens in endodontic infections. (Supported by grant DE015320-01-A1 from NIDCR).