北部某醫學中心急診室及病房血液培養菌種之比較與分析

Comparative Study of the Blood Culture Results of Patients Admitted in the Emergency Room and in the General Ward of a Medical Center in Northern Taiwan

根據前入的報告臨床微生物學及流行病學顯示引起血流感染或菌血症的致病菌正逐年改變。本研究目的將北部某醫學中心急診室及病房血液培養菌種，做一比較與分析。結果顯示兩者血液培養陽性率相當（急診：14.4%，病房：13.496），但急診的污染率3.4%比病房1.7%明顯偏高 （p <0.05），且 coagulase-negative staphylococci（CoNS）在急診佔 22 %，高於病房的1796（p <0.05）。總菌種排行急診第一名為Escherichia coli，病房為CoNS。細菌抗藥性分析，急診病人methicillin-resistant Staphylococcus aerues（MRSA）佔32.4%，低於病房的 51.8%（p<0.05）， 急診病人 extended-spectrum β-lactamase （ESBL）-E. coli. 為 6.996、 ESBL-Klebsiella pneumoniae 為 10%，而病房 ESBL-E. coli 為 8.2%、 ESBL-K. pneumoniae 為 18.396，急診及病房的 ESBL-E. coli及 ESBL-K. pneumoniae無明顯的差異。結論：降低急診血液培養污染率刻不容緩，對於急診病人的血流感染或菌血症，抗生素的經驗性療法需考慮抗藥性問 題。

The clinical microbiological and epidemiological assessments of the cases of bloodstream infection have revealed that the pathogens responsible for bloodstream infections (bacteremia) have changed clinically in recent years. The purpose of this study was to compare the blood culture results of the patients admitted in the emergency room (ER) and those admitted in the general ward (GW) in a medical center in northern Taiwan. We obtained positive blood cultures in the samples of the ER and GW groups, and the rates of positivity were not significantly different (ER: 14.4% vs. GW: 13.4%), but the contamination rate in the blood cultures of the ER group was higher than that of the GW group (ER: 3.4% vs. GW: 1.7%; p < 0.05). Moreover, the incidence of coagulase-negative staphylococci (CoNS) was higher in the ER group than in the GW group (ER: 22% vs. GW: 17%; p < 0.05). The blood culture results showed that the most common pathogens in the ER group and the GW group were Escherichia coli and CoNS, respectively. Analysis of bacterial resistance showed that the incidence of methicillin-resistant Staphylococcus aureus (MRSA) in the ER and GW groups were 32.4% and 51.8% (p < 0.05), respectively. The incidences of extended-spectrum β-lactamase (ESBL)-producing E. coli and ESBL-producing Klebsiella pneumoniae in the ER group were 6.9% and 10%, respectively, and those in the GW group were 8.2% and 18.3%, respectively. Conclusion: Decreased the contamination rate of blood culture of ER was emergent and the empirical therapy of community-acquired bacteremia or bloodstream infection must be considered as the problem for bacterial resistance.