Stochasticity among Antibiotic-Resistance Profiles of Common Burn-Related Pathogens over a Six-Year Period.

backgroundOne of the most significant contributors to morbidity and death in patients with burns is infection, which accounts for 30%-75% of post-burn fatalities. Because of concerns for the development of antibiotic resistance in burn-related pathogens, the aims of this study were to identify antibiotic resistance trends for the four most common burn-related pathogens over a six-year period. PATIENTS AND

methodsThe study used prospectively collected and de-identified aggregate data for all burn patients admitted to the burn unit between 2009 and 2014. The database query included patient demographics along with all data regarding cultures from any source (wound, sputum, urine, stool, blood), which included isolated pathogens and antibiotic resistance profiles. Profiles were then constructed using mean inhibitory concentration standards to determine whether each pathogen was susceptible (S), intermediate (I), or resistant (R) to each antibiotic. The aggregated data were then used to construct a heat map for the four most common pathogens and their resistance profiles over the six-year study period.

resultsThere were 368 patients with burns (248 with positive cultures, 120 with negative cultures) in this study. The positive culture group was significantly older (38 vs. 25 y, p < 0.001) and had longer hospitalizations (17 vs. 11 d, p < 0.01) compared with the negative group. Analysis of antibiotic resistance heat maps constructed for the four most commonly isolated pathogens (methicillin-sensitive Staphylococcus aureus, Enterococcus faecalis, methicillin-resistant S. aureus, Pseudomonas aeruginosa) indicated a lack of notable resistance patterns for any of the individual pathogens.

conclusionsTaken together, these results indicate that there are no discernible patterns of antibiotic resistance across time (six years) for the four most common burn-related pathogens. We conclude that antibiotic choice in burn patients based on previous in-hospital trends may be a flawed strategy. Emerging genomic technology to deliver point-of-care pathogen-specific antibiotic sensitivities via polymerase chain reaction may be needed to more appropriately guide antibiotic choice.