社區診所肺炎鏈球菌之青黴素抗藥性與抗藥基因多型性研究

Penicillin resistance profiles and pbp 2b gene polymorphisms in Streptococcus pneumoniae isolated from community outpatient clinic

歐陽士平(Shih-Ping Ou Yang)

指導教授 ： 張志欽

高雄醫學大學/健康科學院/公共衛生學研究所/碩士(2003年)

摘要

研究目的：
近幾年抗藥性儼然已成為一個全球性的重要議題，台灣之肺炎鏈球菌抗藥性程度為最高的國家之一，據我們所知，國內尚未研究社區診所肺炎鏈球菌之青黴素抗藥性，故本研究主要目的在探討上呼吸道感染的診所病人之肺炎鏈球菌抗藥性情況。
方法：
本研究採用立意取樣(purposive selection)的方式，在2001年11月至2002年3月、2002年12月至2003年1月六家診所中選取上呼吸道感染病人，分離出151株肺炎鏈球菌，以E test測定penicillin最小抑菌濃度(MIC；minimum inhibitory concentration)，PCR方式複製青黴素結合蛋白(pbp2b)基因，並以限制酵素(restriction enzymes) RsaI 及 HaeⅢ決定pbp2b基因型。
結果：
年齡是感染肺炎鏈球菌的危險因子，且達統計上的顯著意義
(P＜0.01)，七歲以下的兒童肺炎鏈球菌抗藥性比例最高。在這些分離菌株中，31.8%中度抗藥性(MIC 0.12-1 μg/ml)；20.5%高度抗藥性
(MIC > 1 μg/ml)。我們發現pbp 2b基因總共有9種不同RFLP型態，83.9%高度抗藥性菌株呈現PCR-RFLP type 3或6。
結論：
台灣目前社區病人肺炎鏈球菌有很高的抗藥性，這個調查可以協助追蹤社區病人肺炎鏈球菌的抗藥性問題及預防菌株的散播。未來仍需脈衝電泳技術及DNA定序做進一步的分析。

關鍵字

肺炎鏈球菌 ； 青黴素結合蛋白 ； 診所

並列摘要

Objective:
In recent years, antibiotic resistance has emerged as an important global problem. High level of antibiotic-resistant is found in Streptococcus pneumonia in Taiwan. To the best of our knowledge, the finding of penicillin resistance profiles in S. pneumonia isolated from community outpatient clinic has not been previously reported. Therefore the objective in this research is to assess the penicillin resistance of pneumococci from outpatients with upper respiratory tract infections and risk factors for carriage.
Method:
During November 2001 to March 2002 and December 2002 to January 2003, 151 isolates of S. pneumoniae were collected from outpatients with upper respiratory tract symptom in 6 clinics. The MIC of isolates were dertermined by E test. The pbp2b gene were amplified by PCR, and the products were digested with restriction enzymes RsaI and HaeⅢ.
Results:
The age is a major risk factor for carriage(P＜0.05). Penicillin-resistant S. pneumoniae (PRSP) rates were highest among persons aged ≦7 years. Of these isolates, 31.8% were penicillin nonsusceptible (MIC 0.12-1 μg/ml) and 20.5% were high-level resistant (MIC > 1 μg/ml). There were 9 PCR-RFLP profiles for pbp 2b gene. 83.9% of isolates with high-level resistant had PCR-RFLP type 3 or 6.
Conclusion:
There is high incidence of penicillin resistance among community isolates of S. pneumoniae in Taiwan. The surveillance of PRSP can help track community resistance problems and prevent the dissemination of S. pneumoniae. In the future, PFGE or DNA sequencing is needed to help define the clonal relationships of the isolates.

並列關鍵字

Streptococcus pneumonia ； penicillin binding protein gene ； Clinics

參考文獻

英文部分

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2.Asahi,Y., Takeuchi,Y., and Ubukata,K. (1999) Diversity of substitutions within or adjacent to conserved amino acid motifs of penicillin-binding protein 2X in cephalosporin-resistant Streptococcus pneumoniae isolates. Antimicrob. Agents Chemother. 43: 1252-1255.

3.Asahi,Y., and Ubukata,K. (1998) Association of a thr-371 substitution in a conserved amino acid motif of penicillin-binding protein 1A with penicillin resistance of Streptococcus pneumoniae. Antimicrob. Agents Chemother. 42: 2267-2273.

4.Baquero,F., Garcia-Rodriguez,J.A., Garcia,d.L., and Aguilar,L. (1999) Antimicrobial resistance of 1,113 Streptococcus pneumoniae isolates from patients with respiratory tract infections in Spain: results of a 1-year 1996-1997 multicenter surveillance study. The Spanish Surveillance Group for Respiratory Pathogens. Antimicrob. Agents Chemother. 43: 357-359.