title: Leukotoxicity of Aggregatibacter actinomycetemcomitans in generalized aggressive periodontitis in Brazilians and their family members.
abstract: OBJECTIVE
  The purpose of this study was to examine the leukotoxin promoter types of Aggregatibacter actinomycetemcomitans clones in subjects with generalized aggressive periodontitis (GAgP) and in their family members (FM).
  
  
  METHODS
  Thirty-five patients with GAgP (33.9±7.1 years), 33 of their FM (22.8±11.4 years), and 41 patients with chronic periodontitis (CP) (44.1±9.4 years) were clinically analyzed using the plaque index, gingival index, probing depth (PD), and clinical attachment level (CAL). Subgingival biofilm samples were collected from four interproximal periodontal sites (>PD and >CAL) of each patient. The presence of A. actinomycetemcomitans and its leukotoxic clone was confirmed by polymerase chain reaction (PCR).
  
  
  RESULTS
  A. actinomycetemcomitans was observed in 23 (51.1%) GAgP patients and 16 (30.1%) CP patients. Thirty-seven (94.8%) patients showed minimally leukotoxic strains and 2 (5.1%) showed highly leukotoxic strains. In the FM group, 10 (30.3%) had aggressive periodontitis (AgP), 12 (36.3%) had CP, 11 (33.3%) were periodontally healthy or had gingivitis, and 12.2% were A. actinomycetemcomitans positive. Greater full mouth PD and CAL were observed in GAgP patients positive for the bacteria than those negative for it (p<;0.05), and the presence of A. actinomycetemcomitans positively correlated with GAgP (Odds ratio, 3.1; confidence interval, 1.4-7.0; p=0.009).
  
  
  CONCLUSIONS
  The presence of A. actinomycetemcomitans was associated with the clinical condition of GAgP, with most patients exhibiting a generalized form of the disease and minimally leukotoxic clones. Most of the relatives of GAgP patients presented either CP or AgP.
authors.affiliation: Graduate Program in Dentistry, Faculty of Pharmacy, Dentistry and Nursing, Federal University of Ceará, FortalezaCE, Brazil.
authors.forename: Virginia Régia Souza
authors.initials: VR
authors.lastname: Silveira
authors.forename: Márcia Viana Bessa
authors.initials: MV
authors.lastname: Nogueira
authors.forename: Nádia Accioly Pinto
authors.initials: NA
authors.lastname: Nogueira
authors.forename: Vilma
authors.initials: V
authors.lastname: Lima
authors.forename: Flávia Aparecida Chaves
authors.initials: FA
authors.lastname: Furlaneto
authors.forename: Rodrigo Otávio
authors.initials: RO
authors.lastname: Rego
mesh_terms: D000328:Adult; D016976:Aggregatibacter actinomycetemcomitans / Q000302:isolation & purification* / Q000472:pathogenicity; D010520:Aggressive Periodontitis / Q000235:genetics / Q000382:microbiology*; D003774:Dental Plaque Index; D005098:Exotoxins / Q000302:isolation & purification*; D005190:Family; D005260:Female; D005891:Gingivitis / Q000382:microbiology; D006801:Humans; D008297:Male; D010512:Periodontal Index; D016133:Polymerase Chain Reaction; D018709:Statistics, Nonparametric
chemical_list: D005098:Exotoxins; C018579:leukotoxin