Ten Year Review of Wound Culture Results and Antimicrobial Resistance Patterns in a Burn Center

Burn patients are susceptible to infections, responsible for up to half of in-hospital deaths. These infections are often caused by multidrug-resistant pathogens, making treatment difficult. This study aimed to assess trends in positive wound cultures during hospitalization in our burn unit over the last decade.

Patients admitted from July 2013 to June 2023 were included. To exclude community-acquired infections, only wound cultures collected after first positive cultures were included. Demographics and information concerning burn injury, admission, and wound cultures were collected. Patients were stratified based on total burn surface area as small (<10%), moderate (10%-19.9%), and severe burns (≥20% total burn surface area). Descriptive statistics were obtained. Generalized linear models were fit to assess the trends of positive cultures and hospital length of stay (LOS) for the three strata.

Percentage of Gram positive, negative, and fungal cultures remained stable over the 10 y. At the species level, Coagulase negative staphylococcus species decreased while Enterococcus species increased over the course of the study. Gram positive strains were most commonly detected in cultures of LOS <1 wk. For LOS up to 2 wks, Gram positive organisms decreased while fungal and Gram negative organisms increased. For LOS ≥ 3 wks, the distribution of positive cultures remained stable. There was an increase in resistance to antibiotics used to treat Gram negative species, and several antibiotics had periods of high resistance preceded by high usage.

Increasing resistance patterns were observed over the years. Stricter indications for antimicrobial prescriptions may be needed to avoid increases in resistance.