Comparison of wound culture and bronchial lavage in the severely burned child - Implications for antimicrobial therapy

Background: The relationship of the burn wound flora to microbial pathogens in the tracheobronchial tree has important implications for antimicrobial therapy in the severely burned patient. Management of septic complications is bolstered by surveillance quantitative wound cultures (QWC) and bronchia l lavage fluid (BLF) cultures. Objectives: To compare the organisms present in ELF with those found in QWC and to determine if QWC can predict ELF results. Design: Results of ELF cultures from all patients who underwent bronchial l avage from January 1, 1996, to December 31, 1996, at our institution were c ompared with QWC data from the same date. Criteria for a positive match inc luded an identical antibiotic susceptibility pattern and biotype. Match rat es were calculated qualitatively and quantitatively. Results: In 30 (48%) of the 62 ELF cultures, there was a match between the organism identified In the ELF and the QWC. When strict quantitative criter ia were applied, the match rate was only 9 (14%) of 62. Burn size and inhal ation injury had no significant effect on match rate. Conclusions: Whereas the microbial pathogens were similar in the QWC and EL F, linear regression showed no value of QWC in predicting ELF culture resul ts. The difference between qualitative and quantitative match rates suggest s cross-colonization between the burn wound and tracheobronchial tree, but little to no cross-infection. The QWC and ELF cultures must be performed in dependently in determining antimicrobial specificity in the burned patient.