Detection of potential biochemical indicators of infection in the burned rat

Severe thermal injury is often complicated by infection. Moreover, the injury itself renders the early detection of infection more difficult. Rapid early detection of infection would thus aid in the treatment of severely burned patients. PCA filtrates of whole blood from burned-infected rats contain three substances that appear to be early indicators of infection in the thermally injured animal. These factors are only slightly affected by the extent of injury. These factors do not appear to be microorganism-specific in that they are found in rats infected with Proteus mirabilis as well as with Pseudomonas aeruginosa. One factor absorbs light at 398 nm and seems to be associated with some cellular component of blood. The other two substances are fluorescent, one λex 280 λem 340 nm, the other λex 355 nm λem 420 nm, and are detectable in PCA filtrates of plasma as well as of whole blood. All factors are retained by filters with a 25,000 dalton pore size. All factors are precipitable from PCA filtrates by phosphotungstic acid, suggesting that they may be proteins. The 355/420 factor increases with oxidation, whereas both the 280/340 substance and the 398 nm material decrease.