Current issues in burn wound infections.
As we have emphasized, the diagnosis of burn wound infections in the high-risk burned child can be difficult and depends on a very high degree of suspicion and daily clinical evaluation of the burn wound site by consistent observers. Appropriate precautions include meticulous hand-washing and the use of gloves when handling the wound site and prophylactic application of a topical antibacterial agent such as SSD cream. Wound therapy should include routine vigorous surgical débridement. Surveillance wound cultures should be done weekly to determine the emergency of colonization and aid in the selection of empiric antimicrobial regimens when these are appropriate. Wound biopsy for histological examination and quantitative culture is highly recommended in the severely ill child with an unclear etiology or site of infection. If, despite these measures, sepsis ensues, then systemic antibiotics must be started empirically as an adjuctive therapy to surgical débridement. Knowledge of the organisms colonizing a wound will prove useful in choosing an antibiotic regimen while awaiting definitive results of blood and wound biopsy cultures. Without this information, early burn sepsis therapy should focus on gram-positive organisms, while infection later in the course should raise suspicion of nosocomial pathogens such as P. aeruginosa, other enteric bacilli, and C. albicans. An initial regimen might include nafcillin plus ceftazidime or an aminoglycoside, with anaerobic coverage depending on considerations noted previously. Once the causative agent is identified, therapy must be modified accordingly. Amphotericin B and acyclovir use should be guided by positive cultures from the burn wound site along with systemic evidence of dissemination. Available studies do not yet make clear the role of empiric immunotherapy with intravenous gamma globulin in the burned child. Therefore, its use cannot be recommended at the present time, although the development of specific immunoglobulins (P. aeruginosa, S. aureus) may prove useful in the future. In view of the multiplicity of organisms that may colonize burn wounds, it is likely that passive immunization may be more useful in the treatment of infection than in its prevention. The switch from P. aeruginosa to, for example, Klebsiella pneumoniae or E. cloacae, is not apt to be particularly beneficial in most circumstances. Similarly, an increased understanding of the role of the immune system in the propensity to burn sepsis may guide the development of vaccines or immunomodulators that decrease the risk of infection in seriously burned children and adults.