| 摘要: | 中文摘要 本研究於2003年2月至6月期間，自台灣中部醫院111位呼吸道及泌尿道感染患者中收集奇異變形桿菌（Proteus mirabilis）菌株，這些菌株的特色為對 ampicillin, gentamicin, amikacin, isepamicin, 及 cefotaxime 具有抗藥性，但是對 ceftazidime (MIC, ≦0.5 mg/ml) 和 meropenem (MIC, <0.5 mg/ml) 卻有很高的敏感性。 111 株奇異變形桿菌株菌中，有 34 株（30.6%）對 Cefotaxime 具有抗性，但在含有乙內醯胺酶抑制劑存在下的表現卻大幅減少。因此推測這 34 株奇異變形桿菌會產生 class A 的超廣效性乙內醯胺酶。利用等電點聚焦電泳，聚合酶連鎖反應及核酸序列分析等方法，我們偵測到 1 株菌株帶有乙內醯胺酶 CTX-M-3 及 TEM-1， 5 株菌株有 CTX-M-3, CTX-M-14 及 TEM-1，19 株菌株有 CTX-M-14 及 TEM-1 ，9株菌株有 CTX-M-14。經由接合試驗結果顯示此多重抗藥性特性可由接合型質體傳遞。使用限制酵素 SfiI 切割及脈衝式膠體電泳法分析後，發現 34 株奇異變形桿菌分成 9 個不同的分子型。將聚合酶連鎖反應的產物進行核酸序列分析，我們偵測到 33 株菌株有 class I integron 基因卡匣及部分菌株帶有插入序列 ISEcp1 含 tnpA 轉位子酶基因。本研究證明這些高比率表現超廣效性乙內醯胺酶 CTX-M 型的奇異變形桿菌首次在台灣被發現。; ABSTRACT Strains of Proteus mirabilis were isolated from patient sufferings by respiratory tract and urinary tract infection during February and June 2003 from middle Taiwan hospitals. These strains were resistant to ampicillin, gentamicin, amikacin and cefotaxime, while they were highly susceptible to ceftazidime (MIC, ≦0.5 mg/ml) and meropenem(MIC, <0.5 mg/ml) were characterized. Out of a total 111 clinical isolates 34 (30.6%) strains exhibited the resistance level to cefotaxime was decreased by the presence of clavulanic acid. Therefore, these strains were speculated to produce extended-spectrum class A b-lactamases. By isoelectric point determination, PCR, and nucleotide sequencing, we detected the presence of CTX-M-3, and TEM-1in 1 strain, CTX-M-3, CTX-M-14, and TEM-1in 5 strains, CTX-M-14 and TEM-1 in 19 strains and CTX-M-14 only in 9 strains. This multiple drug resistance genes were shown to be transferred by a conjugative plasmid. The 34 Proteus mirabilis strains belong to 9 different genotypes were classified by SfiI Pulse Field Gel Electrophoresis (PFGE) patterns. Base on PCR, the sequence of the class I integron with gene cassette in 33 strains and tnpA transposase gene of the insert sequence ISEcp1 in some strains were also detected. In this study, the presence of Proteus mirabilis strains with high percentage CTX-M type of extended-spectrum b-lactamases (ESBLs) was first demonstrated in Taiwan. |
