Division of Infectious Diseases, Department of Internal Medicine, School of Medicine, University of Kansas Medical Center, Kansas City, KS 66160, USA.
Clin Infect Dis. 2009 Dec 15;49(12):e130-8. doi: 10.1086/648442.
There is a paucity of population-based studies on Staphylococcus aureus bacteremia (SAB) in the United States. We determined the incidence of and trends in SAB in Olmsted County, Minnesota, over an 8-year period.
A retrospective, population-based, cohort study was done to evaluate the initial episodes of SAB occurring in adult residents of Olmsted County, Minnesota, from 1 January 1998 through 31 December 2005, using the microbiology databases at Mayo Clinic and Olmsted Medical Center in Rochester, Minnesota.
Of 247 evaluable adult patients with SAB who were included in the incidence calculation, 143 (57.9%) were males, and the median age was 72.1 years (range, 19.5-98.5 years). Episodes of bacteremia were classified according to acquisition type: 58 (23.5%) were nosocomial (N-SAB), 145 (58.7%) were healthcare-associated (HCA-SAB), and 44 (17.8%) were community-acquired (CA-SAB). Methicillin-resistant S. aureus (MRSA) constituted 31.6% of the cases. No community-acquired MRSA bacteremia was noted. The age-adjusted incidence of SAB was 28.3 episodes/100,000 person-years for females and 53.5 episodes/100,000 person-years for males, with an age- and sex-adjusted rate of 38.2 episodes/100,000 person-years. The age- and sex-adjusted incidence of N-SAB, HCA-SAB, and CA-SAB was 9.0, 22.6, and 6.6 episodes/100,000 person-years, respectively. The age- and sex-adjusted incidence of methicillin-susceptible S. aureus was 25.4 episodes/100,000 person-years, and that of MRSA was 12.4 episodes/100,000 person-years. Overall, the incidence rate increased with age but not over the calendar year. The exception was MRSA bacteremia, which increased at a rate of 19.8% (standard error, +/-5.5%) per year during the study.
The incidence of SAB in adults remained stable in Olmsted County, Minnesota, from 1998 to 2005, but the proportion of episodes due to MRSA significantly increased over the 8-year period.
美国目前缺乏关于金黄色葡萄球菌菌血症（SAB）的基于人群的研究。我们确定了明尼苏达州奥姆斯特德县在 8 年期间 SAB 的发生率和趋势。
采用回顾性、基于人群的队列研究，评估 1998 年 1 月 1 日至 2005 年 12 月 31 日期间明尼苏达州奥姆斯特德县成年居民的初始 SAB 发作，使用梅奥诊所和明尼苏达州罗切斯特奥姆斯特德医疗中心的微生物学数据库。
在纳入发病率计算的 247 名可评估的成年 SAB 患者中，有 143 名（57.9%）为男性，中位年龄为 72.1 岁（范围 19.5-98.5 岁）。菌血症发作根据获得类型分类：58 例（23.5%）为医院获得性（N-SAB），145 例（58.7%）为医疗保健相关性（HCA-SAB），44 例（17.8%）为社区获得性（CA-SAB）。耐甲氧西林金黄色葡萄球菌（MRSA）占病例的 31.6%。未发现社区获得性 MRSA 菌血症。女性 SAB 的年龄调整发病率为 28.3 例/100,000 人年，男性为 53.5 例/100,000 人年，年龄和性别调整率为 38.2 例/100,000 人年。N-SAB、HCA-SAB 和 CA-SAB 的年龄和性别调整发病率分别为 9.0、22.6 和 6.6 例/100,000 人年。甲氧西林敏感金黄色葡萄球菌的年龄和性别调整发病率为 25.4 例/100,000 人年，MRSA 为 12.4 例/100,000 人年。总体而言，发病率随年龄增长而增加，但与日历年无关。例外的是 MRSA 菌血症，在研究期间每年以 19.8%（标准误差， +/-5.5%）的速度增加。
1998 年至 2005 年期间，明尼苏达州奥姆斯特德县成年人的 SAB 发病率保持稳定，但 8 年间由于 MRSA 引起的发作比例显著增加。
