DNA Array Profiles Combat Wound Bacteria

A new microbial DNA detection array can find wound bacteria missed by standard culturing (J. Clin. Microbiol. 2014, DOI: 10.1128/jcm.00556-14). The results suggest that the approach could be used to quickly identify pathogens and appropriate treatments. The work was led by Nicholas A. Be and Crystal J. Jaing of Lawrence Livermore National Laboratory. They studied 124 samples taken from 61 wounds in 44 U.S. service members who were injured in combat. The array contains probes for 1,398 bacteria, but others may detect as many as 3,855 bacteria. Array assays can be completed in 24 hours. Using the array, Be, Jaing, and colleagues detected microorganisms in 51% of samples. Standard culturing turned up bacteria in only 35% of samples, likely because some bacteria do not grow well in culture. The researchers found that the presence of Pseudomonas species and Acinetobacter baumannii—and in particular an Acinetobacter plasmid implicated in drug resistance—was associated with failure of wounds to heal. In contrast, the presence of gastrointestinal bacteria species was associated with successful healing.