National statistics don't tell true story of local antibiotic resistance
By Ruth SoRelle, M.P.H.
Antibiotic resistance varies by locale, according to Baylor College of Medicine and Ben Taub General Hospital researchers.
This finding points to the need for more focused surveillance of the issue, the researchers stated in a report that appeared online in the open-access journal BMC Infectious Diseases.
Using samples from more than 20,000 patients taken from 1999 to 2004 at Ben Taub, Lynn Zechiedrich, Ph.D., and her colleagues created a picture of drug-resistant Escherichia coli (E. coli) infections during that period. Such snapshots might be able to provide physicians with pertinent information that could help them identify which drugs are most likely to provide the best treatment, said Zechiedrich, associate professor of molecular virology and microbiology at BCM and senior author of the report.
Need for local snapshot
National studies do not always accurately reflect antibiotic resistance at the local level, she said. For example, the authors noted that levels of resistance to a class of drugs called fluoroquinolones (among them Cipro® or ciprofloxacin) varied by as much as two to four-fold from nationally established rates of approximately 5 percent. Resistant organisms were more often found in men than women, particularly in urinary tract infections and more often in people seen in the hospital than outside.
The male-female finding could occur because men most often have complicated urinary tract infections that require treatment with multiple courses of antibiotics, said Zechiedrich.
Studies such as this are important because they give a clue about how to better treat certain people in certain locales, said Zechiedrich. It could also give clues to trends that might affect the rest of the nation, she said.
"For example, during this study, resistance levels in the United States were about 5 percent," she said. "At Ben Taub and in Houston, they were four-fold higher. Today, however, we see resistance rates of about 20 percent nationwide."
Collaboration important
Compiling and elucidating this kind of data requires massive computer power and people who understand how to extract useful information from large sets of data, said David Steffen, Ph.D., director of the Bioinformatics Research Center at BCM and a co-author of the report.
Zechiedrich noted that Ben Taub's leaders were forward thinking in keeping computer records of this kind, and she credited her graduate student and the report's lead author, Laura Becnel Boyd, with developing and using the tools to make the information usable in this report.
Others who took part in this release include Drs. Robert L. Atmar, Graham L. Randall and Richard J. Hamill, all of BCM. Funding for this work came from the National Institutes of Health, the U.S. Department of Veterans Affairs and the Computational Biology and Medicine Training Programs of the W.M. Keck Center for Computational and Structural Biology of the Gulf Coast Consortia.
The article is available at http://www.biomedcentral.com/content/pdf/1471-2334-8-4.pdf.
