Gamboa Fredy, Acosta Adriana, García Dabeiba-Adriana, Velosa Juliana, Araya Natalia, Ledergerber Roberto
Department of Microbiology, School of Sciences, Pontificia Universidad Javeriana, Bogotá, Colombia.
Dental Research Centre Group, School of Sciences, Pontificia Universidad Javeriana, Bogotá, Colombia.
Acta Odontol Latinoam. 2014;27(3):137-44. doi: 10.1590/S1852-48342014000300007.
Chronic periodontitis is a multifactorial infectious disease associated with Gram-negative strict anaerobes which are immersed in the subgingival biofilm. Porphyromonas gingivalis, an important periodontal pathogen, is frequently detected in patients with chronic periodontitis. Although isolates of P. gingivalis tend to be susceptible to most antimicrobial agents, relatively little information is available on its in vitro antimicrobial susceptibility. The aim of this study was to determine the frequency of P. gingivalis in patients with chronic periodontitis and to assess antimicrobial susceptibility in terms of minimum inhibitory concentration (MIC) of clinical isolates to metronidazole and tetracycline. A descriptive, observational study was performed including 87 patients with chronic periodontitis. Samples were taken from the periodontal pocket using paper points, which were placed in thioglycollate broth. Samples were incubated for 4 hours at 37°C in anaerobic conditions and finally replated on Wilkins-Chalgren anaerobic agar (Oxoid). Bacteria were identified using the RapIDTMANAII system (Remel) and antimicrobial susceptibility was determined with the M.I.C. Evaluator test (MICE, Oxoid). P. gingivalis was identified in 30 of the 87 patients with chronic periodontitis, which represents a frequency of 34.5%. All 30 isolates (100%) were sensitive to metronidazole, with MIC values ranging from 0015-4ug/ml. Regarding tetracycline, 27 isolates (90%) were sensitive, with MIC values ranging from <0.015 to 4 ug /ml, the remaining three isolates (10%) were resistant to tetracycline with MIC values of 8ug/ ml. There was no statistically significant difference in age, gender, pocket depth, clinical attachment level and severity of periodontitis between the group of patients with chronic periodontitis and P. gingivalis and the group of patients with chronic periodontitis without P. gingivalis. In conclusion, P. gingivalis was found at a frequency of 34.5% in patients with chronic periodontitis and clinical isolates were highly sensitive to metronidazole and tetracycline.
慢性牙周炎是一种多因素感染性疾病，与浸没在龈下生物膜中的革兰氏阴性严格厌氧菌有关。牙龈卟啉单胞菌是一种重要的牙周病原体，在慢性牙周炎患者中经常被检测到。虽然牙龈卟啉单胞菌分离株往往对大多数抗菌药物敏感，但关于其体外抗菌敏感性的信息相对较少。本研究的目的是确定慢性牙周炎患者中牙龈卟啉单胞菌的检出率，并根据临床分离株对甲硝唑和四环素的最低抑菌浓度（MIC）评估抗菌敏感性。进行了一项描述性观察研究，纳入了87例慢性牙周炎患者。使用纸尖从牙周袋取样，将其置于硫乙醇酸盐肉汤中。样本在37℃厌氧条件下孵育4小时，最后再接种到威尔金斯-查尔格伦厌氧琼脂（Oxoid）上。使用RapIDTMANAII系统（Remel）鉴定细菌，并通过M.I.C.评估试验（MICE，Oxoid）测定抗菌敏感性。在87例慢性牙周炎患者中，有30例鉴定出牙龈卟啉单胞菌，检出率为34.5%。所有30株分离株（100%）对甲硝唑敏感，MIC值范围为0.015 - 4μg/ml。关于四环素，27株分离株（90%）敏感，MIC值范围为<0.015至4μg/ml，其余3株分离株（10%）对四环素耐药，MIC值为8μg/ml。慢性牙周炎合并牙龈卟啉单胞菌的患者组与不合并牙龈卟啉单胞菌的慢性牙周炎患者组在年龄、性别、牙周袋深度、临床附着水平和牙周炎严重程度方面无统计学显著差异。总之，慢性牙周炎患者中牙龈卟啉单胞菌的检出率为34.5%，临床分离株对甲硝唑和四环素高度敏感。
