Despite great strides made to help soldiers in Iraq survive their wounds, medical personnel in the U.S. military still struggle to treat drug-resistant bacterial infections. This was one the messages presented yesterday at the Interscience Conference on Antimicrobial Agents and Chemotherapy in San Francisco.
Among the most common bacteria to turn up, usually in soldiers' wounds, are methicillin-resistant Staphylococcus aureus (MRSA) and strains of the virulent Klebsiella. The spectrum of bugs harkens back to infections that were common during the Vietnam War, and doctors today are using the same antibacterial drugs as 40 years ago, says Dr. Clinton Murray, one of the presenters at the conference. Murray is an infectious disease specialist at Brooke Army Medical Center in Houston.
Burn wounds are particularly prone to bacterial infections. About 5 percent of combat-related casualties involve burns. At centers including Brooke Army, approximately 75 percent of burn victims suffer from infections, which are the primary cause of death in this group. In most cases, however, soldiers do recover because they do not have complicating conditions like kidney disease and can tolerate the often-toxic drugs that it takes to knock out the bacteria.
Even with these solutions, "we're running out of drugs," says Murray, so the priority of military doctors is to stem these bacteria at their source. Mirroring what doctors see in civilian settings, the transmission of MRSA, Klebsiella and the relatively mild Pseudomonas and Acinetobacter among soldiers is mostly nosocomial, or hospital-associated. To handle these infections, drugs that might otherwise be toxic in older, less healthy populations could be used, and for shorter periods of time to avoid developing resistance, Murray suggests. In addition, the technique of vacuum-assisted closure to draw out liquids when closing wounds has proven useful in reducing the risk of infection.
In the case of MRSA, there is the added complication that about 3 percent of soldiers are colonized before they are deployed. But, given how likely it is for MRSA to reappear even after a patient is "decolonized," Murray does not recommend trying to preemptively decolonize soldiers. Instead, he says that military medical teams should try to keep as many antibacterial drugs at their disposal for when they really need them.
Picture of U.S. soldier courtesy of MATEUS_27:24&25 via Flickr