A new way to combat MRSA infections
Methicillin-resistant Staphylococcus aureus (MRSA) is a type of staph bacteria that is resistant to certain antibiotics called beta-lactams.
According to the website of the Centers for Disease Control and Prevention (CDC) these antibiotics include methicillin and other more common antibiotics
such as oxacillin, penicillin, and amoxicillin.
MRSA is a dangerous infection, difficult to eradicate, that can cause pneumonia or infect wounds and the bloodstream. It is primarily spread through direct
physical contact with a person or object carrying the bacteria, and typically resides on the skin or in the nose. Health care procedures can leave patients
especially vulnerable to MRSA.
According to Makoto Jones, MD, a physician at the VA Salt Lake City Health Care System and an instructor in internal medicine at the University of Utah,
"There is a pressing need for timely, reliable, and generalizable information to guide infection control efforts directed at MRSA within hospitals."
Now, Jones and colleagues from the Salt Lake City and Reno VA medical centers have developed a new way to extract MRSA surveillance data from VA patient
records in order to bolster VA's defenses against this dangerous pathogen.
They recently reported on a study in which they used the new technique to extract data for a 20-year period from all VA health care facilities. Their
results were published in the April 25, 2012 issue of BMC Medical Informatics and Decision Making. i
The team's ultimate goal is to use computer-based health records to uncover, monitor, and fight future outbreaks of the infection in real time throughout
the VA healthcare system and elsewhere. With current and complete data, clinicians will better understand why and how MRSA infections occur. They will be
better able to reduce the number and severity of MRSA outbreaks in hospitals and elsewhere.
The recent report focused on their innovative method for extracting data from VistA, VA's award-winning electronic health records system. The task has been
difficult in the past because of the system's huge size and by differences in the way information is entered by clinicians at the more than 1,400 sites at
which VA provides care to Veterans.
While VA's award-winning medical records system has been used throughout the department for more than twenty years, and all VA facilities use the same
software programs, there is some variation at VA medical centers in the way in which data is named and how it is structured.
Using natural language processing methods, the team analyzed and evaluated more than 33 million unique records from 170 VA hospitals, using data developed
from 1990 through 2009.
Natural language processing is a branch of artificial intelligence that deals with analyzing, understanding, and generating the languages humans speak
naturally in order to interface with computers using natural human languages instead of computer languages.
The team then randomly selected and analyzed 10,000 microbiology reports (reports on organisms, such as bacteria, viruses, and parasites, too small to be
seen by the naked eye) and other documents containing the strings "staph", "coag", "mrsa", "orsa", "oxacillin", or "aureus" and found that by using rules
the team developed, the computer was able to accurately extract cases in which MRSA was present 99.7 percent of the time—a very high rate of accuracy.
"Applying natural language processing methods to microbiology records appears to be a promising way to extract accurate and useful…surveillance methods,"
said Jones. "The dataset constructed and methods used for this investigation could contribute to a comprehensive infectious disease surveillance system,"
allowing VA and other hospital systems to find and deal with MRSA outbreaks nationwide more quickly than they do now.
MRSA infections are usually spread through contact with someone's skin infection or personal items they have used, like towels, bandages, or razors that
touched infected skins. These infections are most likely to be spread in places where people are in close contact with others—for instance, schools and
In health facilities, MRSA is typically spread from patient to patient on unclean hands or through the improper use or reuse of health care equipment. VA
has made it a national priority to reduce MRSA transmission and infection at its health care facilities.
To combat MRSA, VHA obtains nasal specimens from all patients when they are admitted, transferred or discharged; isolates all patients who test positive
for MRSA; emphasizes the importance of thorough hand- washing for all staff; and is working to continuously further improve infection control at all VA
MM Jones, SL DuVall, J Spuhl, MH Samore, C Nielson, M Rubin, "Identification of methicillin-resistant Staphylococcus aureus within the Nation's
Veterans Affairs Medical Centers using natural language processing." BMC Medical Informatics and Decision Making 2012, 12: 34,
doi:10.1186/1472-6947-12-34, published 25 April 2012.