The highly leukotoxic JP2 clone of Aggregatibacter actinomycetemcomitans in localized and generalized forms of aggressive periodontitis

Abstract

Objective: To investigate the presence of A. actinomycetemcomitans, including the highly virulent JP2 clone, in young adult patients with aggressive periodontitis, and associate the findings with the two forms of the disease. Materials and methods: Seventy Moroccan subjects with aggressive periodontitis, aged less than 35 years, were recruited. Among these, 41 had LAgP and 29 had GAgP. Plaque samples were collected from periodontal pockets and examined using a PCR that detects the presence of A. actinomycetemcomitans and which differentiates between JP2 and non-JP2 genotypes of the bacterium. Results : total of 58 (83%) from the 70 AgP patients were positive for A. actinomycetemcomitans, among whom 77% were positives for the JP2 clone. The JP2 clone was detected in 34 (83%) of the LAgP patients compared to 20 (69%) of the GAgP patients (p = 0.17). Fourteen (20%) of the patients harbored non-JP2 genotypes of A. actinomycetemcomitans, although most of these patients (10/14) also harbored the JP2 clone. Conclusions: The presence of the JP2 clone of A. actinomycetemcomitans is strongly associated with both LAgP and GAgP in young adults in Morocco. This implies that treatment of AgP in this population should include microbiological screening and aim at eradication of the bacterium when present.

Key Words::

• aggregatibacter actinomycetemcomitans
• aggressive periodontitis
• highly leukotoxic
• JP2 clone

Acknowledgments

We thank the staff at the Department of Periodontology, University of Rabat, Morocco for assistance during clinical procedure. We are grateful to technical assistant Lise Hald Schultz for help in carrying out the laboratory procedures in Aarhus. Further, we thank Mogens Kilian, from Aarhus, for critical reading of the manuscript and Thomas Vorup-Jensen for kind help. This study was supported by grants from the ‘National center of Technical and scientific research’ (NCTSR, D63/05, Rabat, Morocco) and Aarhus University Research Foundation (F-2002-SUN-1-58 and F-2009-SUN-1-57).

Declaration of interest : The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.