Specific Periodontopathic Bacteria and Salivary Components in Individuals with Down syndrome

众所周知，唐氏综合征(DS)患者往往会发展成严重的牙周病。虽然放线菌伴生放线杆菌被怀疑是一种致病原菌，但目前仍不清楚哪些病原体主要参与其中。本研究通过对DS人群中牙周病原体的调查，确定牙周病的病因是否与特定病原体有关。受试者为120名DS儿童，其中包括60名DS儿童(2~13岁，每个年龄段5名)和60名正常对照，以及62名DS成人(14~57岁)。采用聚合酶链式反应方法，对牙龈下菌斑标本中的10种病原菌进行了检测，包括牙龈卟啉单胞菌、伴生放线菌、福氏拟杆菌、齿密螺旋体、中间普氏杆菌、黑色葡萄球菌、黄色卡诺氏杆菌、芽孢杆菌、直肠弯曲杆菌和腐蚀性艾康氏菌。牙周状况通过牙袋探诊深度、探诊出血和牙周…进行评估牙周状态在DS组和对照组之间没有显著差异，然而，所有病原体在DS组儿童中被检测到的频率更高。在DS儿童的所有年龄段中，福赛瑟氏菌、齿状念珠菌、黑色葡萄球菌和直肠杆菌显著流行(P&lt；0.01或0.05)。铜绿假单胞菌的发生在8岁以上的DS患者中也很显著。对DS受试者的微生物谱进行了聚类分析，结果表明牙周炎与携带病原菌的种类增多和牙周炎病原菌的分布有关。分析了62名14-57岁的DS成人牙周健康或患病的细菌分布。在14-35岁的牙周炎患者中，牙龈假单胞菌的感染率与牙周炎的严重程度有关。然而，大多数年龄较大的DS受试者(36-57岁)尽管有细菌图谱，但仍表现出牙周晚期破坏。为弄清该菌特定的基因型别的流行情况，进一步调查了牙周炎假单胞菌fimA基因的四种基因型在受试者中的分布情况。具有II型或Ib型FIMA基因的牙龈假单胞菌明显占优势，这些结果表明牙周病原体的定植可以发生在DS人群的相当早期的儿童时期。研究还表明，具有特定基因型别的牙龈假单胞菌可促进DS成人的疾病进展。较少

It is widely known that individuals with Down syndrome (DS) often develop severe periodontal diseases. Although Actinobacillus actinomycetemcomitans is suspected to be a causative pathogen, it is still unclear which pathogens are predominantly involved. In this study, we surveyed the periodontal pathogens harboring in DS population to determine if specific pathogens are involved in the etiology of the periodontal diseases.The subjects were 120 children including 60 DS children (2-13 years old, 5 subjects in each age bracket) and 60 agematched controls, and 62 DS adults (14-57 years old). Ten pathogens, Porphyromonas gingivalis, A. actinomycetemcomitans, Bacteroides forsythus, Treponema denticola, Prevotella intermedia, P. nigrescens, Capnocytophaga ochracea, C. sputigena, Campyrobacter rectus, and Eikonella corrodens were surveyed in subgingival plaque samples using a polymerase chain reaction. Periodontal status was evaluated by pocket probing depth, bleeding on probing, and gingival … More index.No significant difference in periodontal status was observed between the DS and control groups, however, all of the pathogens were detected with greater frequency in the DS children. B. forsythus, T. denticola, P. nigrescens, and C. rectus were significantly prevalent throughout all age brackets of the DS children (p<0.01 or 0.05). The occurrence of P. gingvalis was also significant in the DS subjects over 8 years old. A cluster analysis of the microbial profiles of the DS subjects showed that gingivitis was associated with increased varieties of the harboring pathogens and the distribution of P. gingivalis.The bacterial occurrences were analyzed in 62 DS adults (14-57 years old) with healthy or diseased periodontal status. The prevalence of P. gingivalis showed the relationship to severity of periodontitis in 14-35 yeas old DS subjects. Whereas, a majority of the older DS subjects (36-57 yeas old) showed advance periodontal destruction despite of bacterial profiles. To clarify the prevalence of specific genptypes of this organism, the distribition of four genotypes of fimA gene of P. gingivalis was further investigated in the subjects. P. gingivalis possessing type II or type Ib fimA gene was found to be significantly predominant.These results suggest that colonization by various periodontal pathogens can occur in quite early childhood of the DS population. It is also suggested that P. gingivalis with specific genotypes promote the disease progression in DS adults. Less