台灣北區人類、家犬與雞中止蛋之綠膿桿菌抗藥性調查

Abstract

本實驗的目的為比較人類病患、伴侶動物與經濟動物所分離之綠膿桿菌在抗生素敏感性及數種抗藥性基因型的表現。試驗期間，由人類病患分得94株、家犬分得29株以及雞中止蛋分得97株，共220株綠膿桿菌；經確認之菌株分別進行抗生素敏感性試驗、脈衝式電泳及利用聚合酶鏈鎖反應偵測Ambler class A（blaTEM、blaSHV、blaGES、blaVEB、blaPER、blaPSE）與Ambler class D（blaOXA-2 like、blaOXA-10 like）之乙內醯胺酶。 抗生素敏感性試驗結果顯示，所選用之盤尼西林類、頭孢子素類、胺基醣苷類與氟奎諾酮類抗菌劑中，人類病患分離株之抗藥性皆最嚴重，家犬次之，中止蛋最低；對所偵測的抗藥性基因而言，TEM-1在人類、家犬、雞蛋分離株之陽性率分別為90.4%、69.0%與71.1%，PSE-1之陽性率分別77.7%、75.9%與6.2%，OXA-10 like之陽性率則為98.9%、86.2%與18.6%，而乙內醯胺酶SHV、GES、VEB、PER及OXA-2 like皆未在本實驗中被偵測出。經定序後，發現OXA-17及OXA-10兩者為人類與家犬菌株最常及次之常見之OXA酵素；然而，中止蛋分離株所攜帶之OXA-10之陽性率則與OXA-17相近。以65%基因同源性為分類基礎，脈衝式電泳圖譜可將所有收集菌株分成20個clusters，雖然部份之人類與中止蛋分離株似乎有集中在幾個特定clusters之趨勢，但基於綠膿桿菌基因之多變異性，大部分菌株仍分散在不同之clusters。 綜合實驗結果，發現TEM-1、PSE-1與OXA類乙內醯胺酶均廣泛存在於所收集之綠膿桿菌中，人類分離菌株不論在選定藥物之抗藥性或乙內醯胺酶抗藥性基因之陽性率皆高於動物來源之菌株；基於動物與人類因使用不同種類抗菌劑，而對於綠膿桿菌產生不同篩選性壓力的事實，因此，未來擬由探討常用抗菌劑的使用對誘導綠膿桿菌產生抗藥性之關連性，或抗藥性綠膿桿菌在人類與動物之間傳播的可能模式作為進一步研究的方向。

The aims of the study were to survey and differentiate the phenotype and genotype of Pseudomonas aeruginosa from human, companion and economic animal isolates. A total of ninety four human isolates, twenty nine canines isolates and ninety seven chicken isolates used polymerase chain reaction (PCR) to detect the encoding genes of class A (blaTEM, blaSHV, blaGES, blaVEB, blaPER and blaPSE) and class D (blaOXA-2 like, and blaOXA-10 like) β-lactamases. All isolates were also performed antimicrobial susceptibility testing and pulsed-fielded gel electrophoresis (PFGE). Antimicrobial resistance of human isolates were higher than canine isolates, followed by chicken isolates. blaTEM, blaSHV, blaGES, blaVEB, blaPER ,and blaOXA-2 like were not harboured in any isolates. In human, canine and chicken isolates, blaTEM-1 (90.4%, 69.0% and 71.1%), blaPSE-1 (77.7%, 75.9% and 6.2%) and blaOXA-10 like (98.9%, 86.2% and 18.6%) were detected, respectively. OXA-17 was the most common OXA enzyme in human and canine isolates, followed by OXA-10. However, the results of the prevalence of OXA-10 and OXA-17 in chicken isolates were similar (9.3% and 8.2%). All isolates were grouped into twenty clusters by PFGE. Although some isolates from humans or chickens tended to be gathered in specific clusters, other isolates from three sources were mixed together and the result indicated that genetypes of P. aeruginosa are divergent. TEM-1, PSE-1 and OXA-type β-lactamases were widely distributed in Taiwan. The usage of antimicrobial agents and antimicrobial selective pressure might cause great impact on the results. Further surveillance and monitoring the route of resistant genes transmission between P. aeruginosa from difference species and the correlation between antimicrobials and resistant bacteria will be necessary.