Microbiological profile of early onset/aggressive periodontitis patients

Objectives: The objectives of this study were to characterize the bacterial profile and to seek possible bacterial associations in the subgingival microbiota of early onset periodontitis/aggressive periodontitis patients by using two different techniques, culture and immunofluorescence. Material and methods: The study group consisted of 66 systemically healthy individuals with evidence of early onset periodontitis - 41 females and 25 males aged 23-35 years (mean 31.1 +/- 3.1 years). Bacterial samples were collected from the deepest site in each quadrant, resulting in a total of 264 sites with a mean probing pocket depth of 6.6 +/- 1.5 mm. Samples were cultured anaerobically and in 10% CO2 using selective and nonselective media, and isolates were characterized to species level. Indirect immunofluorescence using monoclonal antibodies was applied to detect Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia (Bacteroides forsythus, Tannerella forsythensis), Prevotella intermedia/Prevotella nigrescens, Campylobacter rectus, Peptostreptococcus micros and Actinomyces israelii. Results: 93.6% of sampled sites showed bleeding on probing and 23.5% were positive for suppuration. P. intermedia/P. nigrescens, P. gingivalis, and C. rectus were detected in 77.3-85.9% of samples using culture methods and in 85.6-91.3% using immunofluorescence. P. micros and A. actinomycetemcomitans were found, respectively, in 63.3% and 25.0% of all sites using culturing and in 58.7% and 27.7% sites using immunofluorescence. Significantly strong positive associations were observed between T. forsythia and C. rectus (odds ratio 109.46), and T. forsythia and P. gingivalis (odd ratio 90.26), whereas a negative association was seen between P. intermedia/P. nigrescens and A. actinomycetemcomitans (odds ratio 0.42). Coinfection by P. gingivalis, T. forsythia, P. intermedia/P. nigrescens and C. rectus was observed in 62.1% of the test sites, and in 89.4% of the studied subjects. The sensitivity of immunofluorescence for T. forsythia, C. rectus, P. intermedia/P. nigrescens and P. gingivalis was found to be very high (0.99-0.94) using culture as the reference detection method. The agreement between culture and immunofluorescence in detecting the presence or absence of the investigated species was 85.2-88.1% for P. gingivalis, P. intermedia/P. nigrescens, C. rectus, and T. forsythia, 75.9% for A. actinomycetemcomitans and 70.4% for P. micros. Conclusions: The microbial profile of the early onset/aggressive periodontitis population was complex. The agreement between the two detection methods was very high.