抗藥性腸球菌與鮑氏不動桿菌之主動監測：一項於醫學中心感染科進行之前瞻性研究

Active surveillance culture for vancomycinresistant Enterococci and carbapenemresistant Acinetobacter baumannii in nonintensive care setting: A prospective cohort study in an internal medicine ward in a medical center

多重抗藥性菌種（Multi-drug resistant organisms, MDROs）包含carbapenem-resistant Acinetobacter baumannii（CRAB）以及vancomycinresistant Enterococci（VRE）等，一旦感染MDROs治療選擇有限，主動監測培養是一項應對MDROs重要的感染管制措施。過往文獻對一般病房CRAB及VRE移生之流行病學報告不多，本研究藉由描述分析某醫學中心內科病房CRAB及VRE移生盛行率和發生率，探討主動監測培養的角色。方法：潛在受試者為入住內科一般病房病人，且在過去3個月內未曾住過院、未曾接受過抗生素治療、且無CRAB或VRE移生或感染病史。入院首日採檢腋窩進行CRAB培養、採檢肛門檢體進行VRE培養。於住院5天後或出院前進行複檢。結果：2017年2月1日至2017年7月15日間，共52位病人加入本研究，初檢有4位VRE呈陽性（盛行率76.9‰）、1位CRAB呈陽性（盛行率19.2‰）。40位第一次VRE陰性的受試者接受第二次VRE採檢，7人轉陽性（17.5％，95％信賴區間7.3～32.8）；43位第一次CRAB陰性的受試者接受第二次CRAB篩檢，2人轉陽性（4.7％，95％信賴區間0.5～15.8）。VRE發生率為每萬住院人日數293.4，CRAB發生率為每萬住院人日數76.0。所有受試者之中位數住院天數為10日，有2位死亡，一位死於肺炎，另一位死於胃腸道出血。追蹤之中位數期間為3.5個月（四分位距2.4月～4.5月），期間無受試者得到VRE或CRAB所致的感染。結語：一般病房病人住院中MDRO移生的發生率高，但感染率極低。現行用來篩選MDRO移生病人之危險因子並不全面。在一般病房中進行主動監測培養合併接觸隔離措施，本研究無法證實其效益。 Background: Multidrug resistant organisms (MDROs) include carbapenemresistant Acinetobacter baumannii (CRAB) and vancomycin-resistant Enterococcus (VRE). MDRO infection is associated with higher rates of mortality; therefore, control is important. Current literature on the epidemiology of CRAB or VRE colonization and infection in non-intensive care setting is lacking. This study aimed to investigate the prevalence and incidence of colonization and infection with MDRO in the general ward to provide evidence for infection control strategies. Methods: Patients admitted to a general medical ward were recruited, if they did not have risk factors for MDROs including recent hospitalization or antibiotic use in the preceding 3 months, previous history of colonization, and known risk factors such as tracheostomy or other tubings such as nasogastric tube, urinary catheter, and other drainage devices. At entry, an axillary swab culture for CRAB and an anal swab culture for VRE were collected. A follow-up culture analysis was performed after 5 days or prior to discharge. Results: Fifty-two patients were enrolled between February 1, 2017 and July 15, 2017. At entry, four patients were colonized with VRE and one patient was colonized with CRAB. The prevalence rate at entry for colonization was 19.2 and 76.9 per 1,000 admissions for CRAB and VRE, respectively. Of the 40 patients with initial negative cultures for VRE, seven patients subsequently showed positive results (17.5%, 95% confidence interval [CI]: 7.3~32.8). Similarly, of the 43 patients with initial negative cultures for CRAB, two patients subsequently showed positive results (4.7%, 95% CI: 0.5~15.8). The incidence rate of acquisition of MDROs was 76 and 293.4 per 10,000 patient-days for CRAB and VRE, respectively. The median duration of hospitalization was 10 days. Two patients died during hospitalization, one patient died due to pneumonia, and one patient died due to gastrointestinal bleeding. No patient developed infection from colonization at a median follow up of 3.5 months (IQR: 2.4-4.5). Conclusions: The incidence of colonization with MDROs in the general ward was high; however, the infection rate was low. Risk factors for MDRO was unable to detect all patients with MDRO at admission. This study does not demonstrate the benefit and effectiveness of active surveillance cultures for MDROs combined with contact precautions in the general ward.