加護病房葡萄球菌菌血症及抗藥性之流行病學調查

Epidemiology of Staphylococci Bacteremia and Resistance in Intensive Care Units

本研究目的為探討葡萄球菌菌血症之發生率和抗藥性之趨勢。採回溯性觀察研究法，調查自1990年至2000年期間15歲以上所有住加護病房病人為研究對象，並依據美國疾病管制中心之院內感染定義判斷是否發生院內感染菌血症。研究結果：11年期間加護病房所有轉入或入院病人的葡萄球菌菌血症平均粗發生率為1.76%（195感染人次/住院總人數11,023人次），各年度發生率為0.8%-2.5%之間；經卡方趨勢分析顯示各年度間發生葡萄球菌菌血症之比率，至少有二個不同年度以上的菌血症感染人次具有統計上之顯著差異（p值<0.001）。在所有血液培養陽性中，葡萄球菌菌血症在各年度的分離率互有增減（16.1%-37.7%），平均粗分離率為28.1%；進一步分層分析則金黃色葡萄球菌佔84.1%，其中methicillin抗藥性金黃色葡萄球菌的粗分離率為93.3%；凝固酉莓陰性葡萄球菌菌血症15.9%佔，而對methicillin具抗藥性者也高達93.5%。抗藥性葡萄球菌菌血症各年度均佔所有葡萄球菌菌血症的85%以上，自1996年後至2000年間更高達100%。結論：在院內感染菌血症中，葡萄球菌感染佔1/4以上，尤其是金黃色葡萄球菌，對於methicillin具抗藥性者佔著相當高的比例，而血管內侵入性治療或導管相關裝置適當的臨床照護和落實接觸防護措施是防制葡萄球菌傳播的必要策略。

This study aims to examine the proportion of nosocomial staphylocci bacteremia and resistance in adult intensive care units (ICU). The study was carried out retrospectively, targeting all patients in the adult ICU of a medical center who had developed bacteremia from 1990 to 2000. The results found 195 episodes nosocomial staphylocci bacteremia cases for the study period. The crude infection rate was 1.76% (0.8% to 2.5%). The proportion of staphylocci bacteremia was statistic significantly different between each year by Chi-square for trend test (p < 0.001). Of the positive of blood cultures, the incidence of staphylocci bacteremia was from 16.1% to 37.7% in each year. The average crude infection rate was 28.1%. Further stratified analyze and founded Staphylococcus aurous 84.1%; of them, methicillin - resistant S. aureus (MRSA) was 93.3%; coagulase-negative staphylococci were 15.9%, moreover, with methicillin - resistant 93.5%. Rate of the proportion of resistance to methicillin of staphylocci bacteremia was more than 85% in each year, infection rate reached 100% after 1996.Conclusion: The incidence of nosocomial staphylocci bacteremia in ICU was more than quarter, especially S. aureus and MRSA have high proportion. Catheter associated equipments have well care and well practice of contact precaution, which should be the important strategy for prevention staphylocci widespread in hospital.