Age-related prevalence and characteristics of in periodontitis patients living in Sweden.

: The presence of in patients with periodontitis has been extensively studied for decades. : To study the prevalence of in younger and older periodontitis patients and to genetically characterize isolates of this bacterium. : Data from microbiological analyses of 3459 subgingival plaque samples collected from 1445 patients, 337 'younger' patients (≤35 yrs) and 1108 'older' patients (>35 yrs) during 15 years (2000-2014), has been summerized. Isolates of were serotyped, leukotoxin promoter typed (JP2 and non JP2) and arbitrarily primed PCR (AP-PCR) genotyped. The origin of the JP2 genotype detected in the study population was determined. : The prevalence of was higher among younger than older patients and samples from the younger patients contained higher proportions of the bacterium. Serotype b was more prevalent among younger patients and the majorty of these isolates was from the same AP-PCR genotype. The JP2 genotype was detected in 1.2% of the patients, and the majority of these carriers were of non-African origin. : For presence and charcteristics of in clinical samples the age of the carriers were a discriminating factor. Additional, apparently non-African carriers of the JP2 genotype of were identified.