DNA Detection Speeds Up Wound Bacteria Identification

Photo: A bacterium

"The flora of wound infections is very complex," said Dr. Sydney Finegold from the West Los Angeles Veterans Administration Medical Center. "At times there can be twelve or more organisms present, and most clinical laboratories are not proficient in isolating and identifying anaerobes, which often predominate."

"The big advantage of real-time PCR is that we get quantitative information and accurate identification on the organisms in five hours or so, whereas the current procedure - culturing and identifying organisms by biochemical activity - can take one to several days and sometimes weeks, depending on the organism," he said.

His technique is also useful in detecting flora that can't easily be grown in culture because no one's been able to determine just what the bacteria like in the way of nutrients and environmental conditions.

"When the patient is quite ill, clinicians necessarily use a broad spectrum (antibiotic), hoping not to overlook anything," Finegold said. "The resulting overuse of antibiotics definitely contributes to antibiotic resistance." According to the Centers for Disease Control and Prevention Web site, antibiotic resistance is a growing threat to the general population, as well as the military. In fact, more than 70 percent of the bacteria that cause hospital-acquired infections are resistant to at least one of the drugs most commonly used to treat them.

So far Finegold and colleagues have been able use real-time PCR to detect 20 of the most common bacteria found in wounds, including one, Finegoldia magna, which had been named after him in the past. "Most of us in infectious diseases are looking for ways to speed up microbiologic results so that we can treat more intelligently from the beginning," he said.

COMPAMED.de; Source: US Department of Defense Congressionally Directed Medical Research Programs