碳青黴烯（Carbapenem）抗藥性腸道菌：抗藥機轉與感染控制

腸道菌（Enterobacteriaceae）是臨床上十分重要的致病菌，不論是在社區或醫療環境中皆是如此。隨著抗生素的廣泛使用，腸道菌對抗生素的抗藥性不斷累積、增加。過去二十年間，產生廣效性乙內醯胺酶[extended-spectrum beta-lactamase （ESBL） ]的腸道菌，引起最多的臨床關注；主要原因在於其能水解除了碳青黴烯與頭黴素（cephamycins）外所有的乙醯胺類抗生素（b-lactams）。因此，碳青黴烯類抗生素成為治療產生ESBL 腸道菌的主要藥物。然而隨著碳青黴烯類抗生素的耗用增加，近來碳青黴烯（carbapenem）抗藥性腸道菌（CRE）以其高度抗藥性、缺乏有效治療藥物之姿異軍突起，讓臨床醫師倍感棘手。特別是產生碳青黴烯酶（carbapenemase-producing）的腸道菌，其抗藥性基因大多位於質體上，可以傳遞給其它細菌，造成碳青黴烯抗藥性的快速散播，尤其令人擔憂。因此，對於CRE 進行預防與管制是我們刻不容緩的課題，唯有醫療院所、社區與全民一起攜手合作，做好感染的管控與監控，才能減少CRE 的傳播，降低CRE 對臨床與病患的傷害與衝擊。

Enterobacteriaceae are important pathogens in clinical practice no matter in the community or the hospital. As the clinical usage of antibiotics, rapid emergence of multidrug-resistant Enterobacteriaceae is noted recently. In the past two decades, extended-spectrum beta-lactamase (ESBL) caused the most clinical concerns because these enzymes would hydrolyze all beta-lactams except carbapenems and cephamycins. Therefore, carbapenems are the most important agents to treat infection caused by ESBL-producing Enterobacteriaceae. However, carbapenem-resistant Enterobacteriaceae (CRE) emerges soon after increased consumption of carbapenems. Because of extensive resistance and limit in treatment choice, CRE arouses more clinical concerns than ESBL-producing Enterobacteriaceae. In addition, some of the resistant genes of CRE are located in the plasmid that could be transmitted to other bacteria. This might result in rapid spread of carbapenem resistance. Thus, to control spreading of CRE is an important clinical issue. As the characteristics of Enterobacteriaceae, intervention strategy should be conducted in both community and healthcare settings to prevent spread of CRE.