Prevalence and distribution of Aggregatibacter actinomycetemcomitans and its cdtB gene in subgingival plaque of Chinese periodontitis patients

Abstract

BackgroundAggregatibacter actinomycetemcomitans (A.actinomycetemcomitans) is an important periodontal pathogen that can participate in periodontitis and other non-oral infections. The cytolethal distending toxin (Cdt) is among the virulence factors produced by this bacterium. This study was to elucidate the distribution of A.actinomycetemcomitans and the prevalence of its cdtB gene in Chinese subjects.MethodsA total of 255 subgingival samples were obtained from 30 subjects. Samples were collected from periodontal healthy sites as well as shallow, moderate and deep pockets. The absolute quantity of A.actinomycetemcomitans and cdtB gene were determined by real-time polymerase chain reaction.ResultsA.actinomycetemcomitans was detected in 92 of 105 (87.6%) samples of aggressive periodontitis (AgP) patients, in 73 of 79 (92.4%) samples of chronic periodontitis ( CP) patients and in 5 of 71 (7.0%) samples of periodontal healthy subjects. The cdtB gene was detected in 72 sites (78.3%) with AgP infected with A.actinomycetemcomitans, 54 sites (74.0%) with CP infected with A.actinomycetemcomitans and none in healthy sites infected with A.actinomycetemcomitans. In addition, quantity of A.actinomycetemcomitans and cdt gene in samples from deep pockets were significant larger than moderate, shallow and healthy sites (P < 0.05). In comparison to CP, AgP patients were infected with increased numbers of cdt genotype in deep pockets (P < 0.05).ConclusionThis study suggests that the cdtB gene are prevalent in A.actinomycetemcomitans, and the distribution of cdt genotype strain may be correlated with AgP and serious periodontal inflammation.

Do patients with aggressive and chronic periodontitis exhibit specific differences in the subgingival microbial composition? A systematic review

“…4,19,27,[29][30][31][32][33][34][35] A total of 6,376 patients (AgP = 1,978 and CP = 4,398) and 23,920 subgingival biofilm samples were evaluated (AgP = 8,224 and CP = 15,696). The samples were analyzed individually in 26 studies 3,5,6,18,20,[23][24][25]27,29,30,32,33,44,46,57,59,71,[73][74][75][76][77]82,84,85 and pooled in 28 studies. 4,16,17,19,21,22,26,28,31,34,35,[38][39][40][41]…”

“…Aggregatibacter actinomycetemcomitans 13 3,16,17,33,36,41,45,47,72,[77][78][79][80] 0 24 [4][5][6][18][19][20]22,24,27,29,30,32,38,39,42,46,49,57,59,73,74,76,81,82 Moderate Fusobacterium nucleatum 3 6,75,77 0 1 4 5,16,17,19,29,[33][34][35]38,43,57,73,74,79 Parvimonas micra 3 33,34,57 0 1 5 [4]…”

Impact of CDT Toxin on Human Diseases

“…A. actinomycetemcomitans is a bacteria frequently associated with periodontitis [ 54 ], and numerous studies have found that the majority of these strains harbor CDT (from 66% to 86% depending on the study) [ 50 , 54 , 55 , 56 ]. Periodontitis is an inflammatory state of the tooth-supporting structures (gingiva, alveolar bone, periodontal ligament and cementum).…”

Cytolethal Distending Toxin: A Unique Variation on the AB Toxin Paradigm

“…Data from some studies have indicated a correlation between the presence of Cdt + A. actinomycetemcomitans strains and periodontal disease while other studies have failed to find a difference between colonization of subjects with disease by Cdt + and Cdt − strains. A representative collection of studies in which Cdt + and Cdt − strains of A. actinomycetemcomitans were quantified by either culturing or PCR in localized aggressive periodontitis (LAP) subjects and clinically healthy controls yielded mixed results in relation to a positive correlation between the toxin and disease [19,[191][192][193][194][195][196][197]. In one of these studies, a random cohort of 500 Ghanaian adolescents (mean age 13 years) was examined for the presence of A. actinomycetemcomitans and expression of the AaCdt at baseline and in 397 of the subjects two years later [191].…”