Flournoy D J
Pathology and Laboratory Medicine Service, Veterans Affairs Medical Center, Oklahoma City, OK 73104, USA.
J Okla State Med Assoc. 1997 Jul-Aug;90(6):228-35.
Methicillin-resistant Staphylococcus aureus (MRSA) isolates are endemic at the Veterans Affairs Medical Center in Oklahoma City. Five hundred and four consecutively occurring pathogenic MRSA from 490 in-patients were characterized from 1986-96 in order to better understand their epidemiology. The percentage of S. aureus resistant to methicillin increased steadily for 8 years then unexpectedly began decreasing in 1994. During the study period there was a decrease in nosocomial MRSA from wounds and urines with an increase in community-acquired MRSA from sputa and wounds. However, 72% of all isolates from 1986-96 were nosocomial. MRSA from intensive care unit (ICU) patients were more likely to come from respiratory tract specimens than MRSA from non-ICU patients. During the study period, increases in the proportions of nosocomial MRSA from ICU patients and community acquired MRSA from ICU and non-ICU patients occurred. MRSA with many phenotypes (i.e., 69) were identified, suggesting a divergent (versus univergent) threat to patients. Phenotypic analyses, weekly tabulations, and other evidence suggested that MRSA from 3 of the 69 phenotypes were epidemic strains, occurring around 1989. This 11-year descriptive study revealed the epidemiology of MRSA to be a continuously evolving, complicated multifactoral process.
耐甲氧西林金黄色葡萄球菌（MRSA）菌株在俄克拉何马城退伍军人事务医疗中心呈地方性流行。为了更好地了解其流行病学特征，对1986年至1996年期间490名住院患者中连续出现的504株致病性MRSA进行了特征分析。对甲氧西林耐药的金黄色葡萄球菌百分比连续8年稳步上升，然后在1994年意外开始下降。在研究期间，医院获得性MRSA在伤口和尿液中的比例下降，而社区获得性MRSA在痰液和伤口中的比例增加。然而，1986年至1996年期间所有分离株中有72%是医院获得性的。重症监护病房（ICU）患者的MRSA比非ICU患者的MRSA更有可能来自呼吸道标本。在研究期间，ICU患者的医院获得性MRSA以及ICU和非ICU患者的社区获得性MRSA的比例均有所增加。鉴定出具有多种表型（即69种）的MRSA，这表明对患者存在不同（而非单一）的威胁。表型分析、每周统计以及其他证据表明，69种表型中的3种MRSA为流行菌株，大约出现在1989年。这项为期11年的描述性研究表明，MRSA的流行病学是一个不断演变、复杂的多因素过程。
