Clinical Trial: Virulence Determinants in S Aureus Bacteremia

Study Status: Completed
Recruit Status: Completed
Study Type: Observational

Official Title: Virulence Determinants in Staphylococcus Aureus Bacteremia

Brief Summary: The purpose of this study is to investigate why some people develop life-threatening infections caused by the bacteria Staphylococcus aureus, while other people do not. It is possible that the infectious ability of the bacteria can determine whether an infection develops and its severity. The investigators will look at old blood and nasal specimens collected from 1000 adults who had S. aureus infections and who were hospitalized at Duke University Medical Center. Previously collected health information regarding these patients and the specific bacterial traits in the samples will be studied. Eventually this information may be used to help treat and prevent S. aureus infection.

Detailed Summary: The purpose of this study is to more thoroughly investigate the impact of bacterial genetic characteristics on the outcome of patients with S. aureus bacteremia (SAB). The investigators will address salient aspects of bacterial virulence using strong collaborative relationships with authorities in bacterial genetics and genomics. The overall hypothesis of this investigation is that distinct bacterial virulence determinants influence the severity of S. aureus infection. The specific hypothesis is that virulence determinants associated with clinical outcome of S. aureus infection segregate into clonal groups, identified by Multilocus Sequence Typing (MLST), and can be localized in the genome by comparative genetic hybridization (CGH). The investigators have established the following aims to pursue this hypothesis. Specific Aim 1: Define the allelic diversity of S. aureus bloodstream isolates using MSLT. Allelic profiles among the 1000 isolates will be compared using the program BURST (Based Upon Related Sequence Type), and relatedness of lineages in the overall collection will be defined. Specific Aim 2: Define the genomic diversity of S. aureus bloodstream isolates using CGH. Using MLST results, a subset of 200 isolates will be selected to undergo further study. These ~200 isolates will form a unique collection hereafter referred to as the SAGA (S. aureus genomic analysis) collection. The genomic diversity of the SAGA subset will be defined using CGH. Specific Aim 3: Correlate MLST and CGH results, MLST and clinical outcome, and CGH, and clinical outcome, and make SAGA isolates available to the scientific community. In this Specific Aim, the discriminate ability of MLST and CGH will be compared among the SAGA subset isolates undergoing both assays. The association between bacterial clonality and clinical outcome will be considered among 1000 S. aureus isolates collected from adults at Duke University Medical Center who had S. aureus infections undergoing MLST. The as
Sponsor: Duke University

Current Primary Outcome: Cure vs. recurrence of Staph infection vs. death [ Time Frame: 12 weeks ]

Original Primary Outcome:

Current Secondary Outcome:

Original Secondary Outcome:

Information By: Duke University

Dates:
Date Received: April 27, 2006
Date Started: March 2004
Date Completion:
Last Updated: April 26, 2016
Last Verified: April 2016