title: Aggregatibacter actinomycetemcomitans and its relationship to initiation of localized aggressive periodontitis: longitudinal cohort study of initially healthy adolescents.
abstract: Aggregatibacter actinomycetemcomitans is frequently associated with localized aggressive periodontitis (LAP); however, longitudinal cohort studies relating A. actinomycetemcomitans to initiation of LAP have not been reported. A periodontal assessment was performed on 1,075 primarily African-American and Hispanic schoolchildren, ages 11 to 17 years. Samples were taken from each child for A. actinomycetemcomitans. A cohort of 96 students was established that included a test group of 38 A. actinomycetemcomitans-positive students (36 periodontally healthy and 2 with periodontal pockets) and 58 healthy A. actinomycetemcomitans-negative controls. All clinical and microbiological procedures were repeated at 6-month intervals. Bitewing radiographs were taken annually for definitive diagnosis of LAP. At the initial examination, clinical probing attachment measurements indicated that 1.2% of students had LAP, while 13.7% carried A. actinomycetemcomitans, including 16.7% of African-American and 11% of Hispanic students (P = 0.001, chi-square test). A. actinomycetemcomitans serotypes a, b, and c were equally distributed among African-Americans; Hispanic students harbored predominantly serotype c (P = 0.05, chi-square test). In the longitudinal phase, survival analysis was performed to determine whether A. actinomycetemcomitans-positive as compared to A. actinomycetemcomitans-negative students remained healthy ("survived") or progressed to disease with attachment loss of >2 mm or bone loss (failed to "survive"). Students without A. actinomycetemcomitans at baseline had a significantly greater chance to remain healthy (survive) compared to the A. actinomycetemcomitans-positive test group (P = 0.0001). Eight of 38 A. actinomycetemcomitans-positive and none of 58 A. actinomycetemcomitans-negative students showed bone loss (P = 0.01). A. actinomycetemcomitans serotype did not appear to influence survival. These findings suggest that detection of A. actinomycetemcomitans in periodontally healthy children can serve as a risk marker for initiation of LAP.
authors.affiliation: Department of Oral Biology, University of Medicine and Dentistry of New Jersey, Newark, NJ 07101, USA. finedh@umdnj.edu
authors.forename: Daniel H
authors.initials: DH
authors.lastname: Fine
authors.forename: Kenneth
authors.initials: K
authors.lastname: Markowitz
authors.forename: David
authors.initials: D
authors.lastname: Furgang
authors.forename: Karen
authors.initials: K
authors.lastname: Fairlie
authors.forename: Javier
authors.initials: J
authors.lastname: Ferrandiz
authors.forename: Cebile
authors.initials: C
authors.lastname: Nasri
authors.forename: Marie
authors.initials: M
authors.lastname: McKiernan
authors.forename: John
authors.initials: J
authors.lastname: Gunsolley
mesh_terms: D000293:Adolescent; D001741:Black or African American; D016301:Alveolar Bone Loss; D002648:Child; D015331:Cohort Studies; D005260:Female; D006630:Hispanic or Latino; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D015661:Pasteurellaceae / Q000145:classification / Q000302:isolation & purification*; D010518:Periodontitis / Q000382:microbiology* / Q000473:pathology; D016300:Radiography, Bitewing; D012307:Risk Factors; D012703:Serotyping