Multi-Center Clinical Performance Evaluation of a Rapid In Vitro Diagnostic Device for Direct Detection of Staphylococcus aureus Nasal Colonization: Comparitive Analysis to Culture Screening Method.

The Centers for Disease Control and Prevention (CDC) defines Staphylococcus
aureus as a common bacterium found on the skin and in the nose of some people
(1). The nares have been defined as the most consistent area in which
asymptomatic colonization of Staphylococcus aureus can be found and accounts
for approximately 25% - 30% of the population (1, 2, 3). Different colonization
patterns such as Persistent Carriers (almost always carry), Intermittent
Carriers and Non- Carriers (almost never carry) may play a key role in defining
the epidemiology and pathogenesis of infection (2). Staphylococcus aureus is
considered to be an important nasal pathogen that accounts for approximately
20% of surgical-site infections (3, 4, 5, 22, 23). Over the past 50 years the
treatment of infections with antibiotics have proven more difficult as
resistance of Staphylococcus aureus (Methicillin Resistant Staphylococcus
aureus: MRSA) has increased with the more commonly used penicillin-related
antibiotics (1). In addition to Staphylococcus aureus, other Staphylococcus
species, such as the Coagulase-Negative Staphylococci (CoNS) are increasingly
important nasal colonizers that have been isolated in the clinical laboratories.

The CoNS account for about 20 different species and are often considered a
single group that are also associated with hospital infections and multi-drug
resistance. Data from the National Nosocomial Infections Surveillance System,
1986-1996 (NNIS), prioritized a panel of pathogens isolated from surgical site
infections. The most common pathogens included were: Staphylococcus aureus,
Coagulase-Negative Staphylococci (CoNS), Enterococcus spp., Escherichia coli,
Pseudomonas aeruginosa and Enterobacter spp., (6). Nasal carriers of potential
surgical site infection pathogens, such as Staphylococcus aureus are leading to
the development of new to the market rapid detection devices for screening
subjects.

The purpose of the study is to collect nasal swabs to establish clinical
performance data of the 3M SA Detector, which will be included in the device
instructions for use, claims and support regulatory submissions and design
validation requirements applicable to quality systems.

The objective of the study is to establish the 3M SA Detector clinical test
performance characteristics of sensitivity, specificity and predictive values
for direct detection of Staphylococcus aureus nasal colonization against
clinical microbiology laboratory culture methods.

Sampling:
The clinical sampling is non-blinded and non-randomized. The SAD devices will
be packaged in bulk. Study personnel will mark the tubes with the subject
number and the order of sampling: *1* for first sample taken, and *2* for the
second sample per subject. Two nasal specimens will be collected from each
subject. The SAD devices, however, will be randomized to the method of analysis
(SA Device and SA Quantitative Analysis versus SA Semi-Quantitative Analysis),
using a blinded randomization scheme prior to transport to the clinical lab.
The samples will be transported to the microbiology laboratory utilized by the
site. At the end of the study, leftover eluates, swabs and cartridges will be
frozen, stored and shipped to the sponsor for testing at a later date as needed
and ultimately destroyed.

Study Duration:
One visit is required per subject for study enrollment and nasal sampling
during preoperative visit. It is expected that this visit will be less than one
hour. The study is to be completed in approximately 16 weeks.

There are no anticipated or known health risks associated with participation in
this study. The dry rayon fiber bud of the SAD is the only swabbing component
that will make contact with the human nasal mucosa. The swab buds are
commercially available fiber materials. The incidence and severity of
irritation is expected to be low or not detectable.