Rapid Identification of Key Pathogens in Wound Infection by Molecular Means

The military is subject to traumatic wounds of various types and severity. Such wounds are predisposed to infection because they 1) tend to be extensive and deep, 2) may affect areas of normal carriage of potentially pathogenic bacteria in the gastrointestinal tract, upper respiratory tract, and the female genital tract, 3) typically produce tissue damage, 4) may introduce foreign bodies, 5) may interfere with local blood supply, 6) tend to produce ischemia, edema and hemorrhage, 7) may be complicated by fractures or burns and 8) may lead to shock and overwhelming of the body's systemic defenses. It will not always be possible in the military setting to cleanse and debride the wound promptly and effectively or to promptly provide surgery in the event of damage to vital structures. In the active military setting, the probability of wound infection following trauma is relatively high. In the absence of rapid identification of infecting flora and provision of information on antimicrobial susceptibility, clinicians must resort to empiric therapy rather than a tailored therapy. There is a tendency to use one of the top available agents that would likely be active against the vast majority of bacteria. This leads to increases in antimicrobial resistance, an important problem. The investigators hypothesize that the use of molecular biology techniques will provide identification of the microorganisms responsible for wound infection more rapidly and accurately. The investigators will evaluate real-time PCR (polymerase chain reaction) technique under this proposal. This procedure can be applied directly to material from the wound without need for first growing the organisms. It can be used to define the total flora of the wound within five hours. The investigators will first develop primers and probes that will detect the various bacteria anticipated in a given wound in a certain location. These primers and probes will be used in real-time PCR for rapid and accurate identification of the wound flora. The information obtained with real-time PCR is quantitative so that one may judge the relative importance of different isolates. The investigators will also use another molecular approach, 16S rRNA gene cloning, and conventional cultures; these will provide further information about the flora of various wounds. Definitive identification of anaerobes can be provided quickly and that, along with information on usual antimicrobial susceptibility patterns, can be life-saving or shorten the course of the infection considerably.