Recurrent MRSA Infections: A Study of Risk Factors and Molecular Epidemiology

复发性 MRSA 感染：危险因素和分子流行病学研究

• 批准号: 8660603
• 负责人: Michael Zdenek David
• 金额: $ 12.66万
• 依托单位: UNIVERSITY OF CHICAGO
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-06-01 至 2016-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8660603
• 关键词: Aftercare; Anatomic Sites; Antibiotic Therapy; Antibiotics; Biology; Blood; Caring; Case-Control Studies; Characteristics; Chicago; Chronic; Clinical; Cohort Studies; Collection; Communicable Diseases; Communities; Comorbidity; Complement; Databases; Diagnosis; Disease; Ecology; Enrollment; Environment; Epidemic; Epidemiology; Exposure to; Future; Gastrointestinal tract structure; Genetic; Genetic Predisposition to Disease; Genotype; Goals; HIV; Healthcare; Healthcare Systems; Household; Human; Incidence; Individual; Infection; Intervention; Jail; Life; Literature; Medical; Medical Records; Medical center; Modality; Molecular Epidemiology; Monitor; Monobactams; Nose; Organism; Patients; Pneumonia; Population; Predisposition; Prospective Studies; Protocols documentation; Recurrence; Recurrent disease; Reporting; Research; Research Personnel; Risk; Risk Factors; Role; Safety; Sepsis; Site; Skin; Skin Tissue; Soft Tissue Infections; Specialist; Staphylococcus aureus; Surveillance Program; Techniques; Time; United States; Universities; Vaccines; burden of illness; clinical epidemiology; cohort; demographics; high risk; medical attention; men who have sex with men; methicillin resistant Staphylococcus aureus; microbial; pathogen; patient oriented; prevent; prospective; public health relevance; resistant strain; skills; stem; surveillance data

DESCRIPTION (provided by applicant): Staphylococcus aureus is among the most common bacterial pathogens in human beings. The epidemiology of methicillin-resistant S. aureus (MRSA), which are strains resistant to all ¿-lactam antibiotics, has changed dramatically in the past fifteen years. While MRSA infections before that time occurred almost exclusively within the health care environment and in patients with health care exposure, since the mid-1990s, new strains of MRSA have arisen that are causing an epidemic of infections in the community, particularly skin and soft tissue infections but also less common severe, invasive infections. These community-associated (CA-) MRSA strains differ from the older healthcare-associated (HA-) MRSA strains in the population that they infect, in the type of infections that they cause, and in the genetic characteristics of the strains themselves. MRSA is often a commensal organism, living on the skin, in the gastrointestinal tract, and in the nose of individuals, and asymptomatic carriage is thought to be common before an infection occurs. MRSA infections often recur in patients, but it is not known which patients are at highest risk for recurrence nor whether CA- or HA-strains are more likely to cause recurrence. In the era of CA-MRSA, it is not known if patients with persistent carriage of MRSA are at elevated risk of recurrent MRSA infections. There are interventions that may decrease the likelihood of recurrent MRSA infections in an individual: decolonization protocols, cleaning of fomites, antibiotic therapies, and vaccines are all potentially relevant avenues for the future control of MRSA in the community. Each of these modalities will require further study to assess its efficacy and safety. Patients with recurrent MRSA disease are likely to benefit from such interventions, and the control of MRSA infections in this population may be critical to stemming the dissemination of CA-MRSA in the U.S. In this a two-part study, using a collection of >13,800 stored clinical S. aureus strains, obtained through surveillance at the University of Chicago Medical Center (UCMC), I will attempt to define risk factors for recurrent MRSA infections. First, using existing surveillance data from UCMC in 2003-9, in a case-control study treating those with multiple infections as the cases and those with a single infection as controls, I will examine the following as risk factors for re- infection: anatomic site of first infection, genotype of first and subsequent infecting MRSA strains including CA- and HA-MRSA strain characteristics, patient demographic characteristics, previous exposures to the health care system, and patient comorbidities. Second, nesting a prospective cohort study of recurrent MRSA infections in surveillance at UCMC, I will enroll 400 patients with incident MRSA infections and monitor them for two years. I will determine how frequently these patients have recurrent MRSA infections, how commonly they seek medical attention for the infections, the presence of the risk factors for re-infection listed above, and the genotypes of MRSA strains associated with infections and any identified asymptomatic colonization to assess the role of chronic colonization in the recurrence of MRSA infections. Public Health Relevance: Infections caused by methicillin-resistant Staphylococcus aureus (MRSA), once limited to patients with exposures to the health care system, are becoming common in the healthy population of the United States. While many people have recurrent skin, blood or other MRSA infections after treatment for a first infection, it is not known which patients are at high risk for such recurrences. The goal of this study is to determine the risk factors that predict recurrent MRSA infections by studying the demographics, medical treatments given, and medical problems of MRSA patients, the types of infection caused by MRSA, and the genetic characteristics of MRSA strains that cause initial and recurrent infections.

描述（由申请人提供）：金黄色葡萄球菌是人类最常见的细菌病原体之一。耐甲氧西林金黄色葡萄球菌（MRSA）是对所有内酰胺类抗生素耐药的菌株，其流行病学在过去15年中发生了巨大变化。在此之前，MRSA感染几乎只发生在卫生保健环境中和接触卫生保健的患者中，但自20世纪90年代中期以来，出现了新的MRSA菌株，导致社区感染流行，特别是皮肤和软组织感染，但也有不太常见的严重侵袭性感染。这些社区相关（CA-） MRSA菌株不同于较老的医疗保健相关（HA-） MRSA菌株，在它们感染的人群中，在它们引起的感染类型和菌株本身的遗传特征上。耐甲氧西林金黄色葡萄球菌通常是一种共生生物，存在于个体的皮肤、胃肠道和鼻子中，在感染发生前无症状携带被认为是常见的。MRSA感染经常在患者中复发，但不知道哪些患者复发的风险最高，也不知道CA-株或ha -株是否更容易引起复发。在CA-MRSA时代，尚不清楚持续携带MRSA的患者是否具有复发性MRSA感染的高风险。有一些干预措施可以降低个体MRSA复发感染的可能性：去菌落方案、清洁污染物、抗生素治疗和疫苗都是未来控制社区MRSA的潜在相关途径。每一种方式都需要进一步研究以评估其有效性和安全性。MRSA复发性疾病的患者可能会从这些干预措施中受益，并且在这一人群中控制MRSA感染可能对阻止CA-MRSA在美国的传播至关重要。在这项由两部分组成的研究中，我将尝试定义MRSA复发性感染的危险因素，该研究使用了芝加哥大学医学中心（UCMC）通过监测获得的1,13800个储存的临床金黄色葡萄球菌菌株。首先，利用UCMC 2003- 2009年现有的监测数据，在一项病例对照研究中，我将多次感染作为病例，单次感染作为对照，检查以下再次感染的危险因素：首次感染的解剖部位，首次感染和随后感染的MRSA菌株的基因型，包括CA-和HA-MRSA菌株特征，患者人口统计学特征，以前与卫生保健系统的接触，以及患者的合并症。其次，在UCMC进行复发性MRSA感染监测的前瞻性队列研究，我将招募400名发生MRSA感染的患者，并对他们进行两年的监测。我将确定这些患者复发MRSA感染的频率，他们为感染寻求医疗护理的频率，上述再次感染的危险因素的存在，以及与感染相关的MRSA菌株的基因型和任何已确定的无症状定植，以评估慢性定植在MRSA感染复发中的作用。