2012-08-012024-05-13https://scholars.lib.ntu.edu.tw/handle/123456789/645315摘要：甲氧苯青黴素抗藥性金黃色葡萄球菌（MRSA）是臨床上重要的致病菌之一，可以引起人體各種部位的感染；其中以菌血症是特別引人重視的感染症，最主要原因在於其可導致明顯的死亡率與併發症。在過去許多的研究，指出了各種和MRSA菌血症預後相關的因素，主要包括宿主的狀況不佳、菌血症的嚴重程度過高、致病菌株帶有特殊的毒力因子或會分泌特殊的外毒素、以及致病菌株對治療用抗生素的反應不佳等。然而，在這些眾多的因素當中，血中菌量高低與菌量改變情形對MRSA菌血症預後的影響，卻鮮少被人談論到。而過去對使用各種不同抗生素治療MRSA菌血症，是否對預後有所影響的研究，幾乎都以死亡率作為研究的endpoint。在這樣的研究設計下，受到宿主因素的干擾過大，即便某些抗生素在體外環境業已證實其殺菌速度遠優於其它抗生素，仍無法被證實其在體內環境有著明顯優勢的療效。若改以血中菌量改變的速度來作為end point，可能比較有機會證明不同抗生素間在療效上的差別。本研究計畫，即針對上述問題加以設計；利用定量即時聚合酶鏈鎖反應來定量血中MRSA的菌量。在考慮其它眾多因素的干擾下，嘗試釐清血中菌量改變對MRSA菌血症預後之影響，以及不同抗生素是否對MRSA菌血症有著不同的療效（主要針對vancomycin及datpomycin之比較）。<br> Abstract: Methicillin-resistant Staphylococcus aureus (MRSA) is a major pathogen to cause various infections. Among these infection syndromes, bloodstream infection (BSI) is of most concern because of significantly additional mortality and morbidity. Several previous reports have demonstrated some important risk factors for mortality among patients with MRSA BSI, including poor host conditions, severity of MRSA BSI at presentation, production of specific virulent factors or exotoxins by the causative MRSA isolates, and poor response to antibiotics of the causative MRSA isolates. However, the impact of bacterial load and change of bacterial load after effective antibiotics on the mortality of MRSA BSI is seldom discussed.Prior studies comparing the treatment effectiveness or efficacy between different antibiotics used in MRSA BSI usually use mortality as the primary endpoint. However, under such study design, the effectiveness or efficacy of the concerned therapeutic agents are inevitably confounded by the host conditions, which usually lead to that no significant difference in mortality between patients using different therapeutic agents can be demonstrated. Under such situation, using change of blood MRSA load as the endpoint might have more chance to illuminate the difference in the therapeutic effectiveness or efficacy.This study is designed according to the rational described above. Quantitative real-time polymerase chain reaction will be used to quantify the blood bacterial load in patients with MRSA BSI. Various confounding factors will be considered at the same time in our present study to investigate the potential role of blood bacterial load in prognosis of MRSA BSI; and the effectiveness of different therapeutic agents, focus on vancomycin v.s. daptomycin, on the change of serial blood bacterial load will also be evaluated at the same time.甲氧苯青黴素抗藥性金黃色葡萄球菌血中菌量定量即時聚合酶鏈鎖反應Methicillin-resistant Staphylococcus aureusblood bacterial loadquantitative real-time polymerase chain reaction