Objective:
Burn-injured patients are highly susceptible to infectious complications, which are often associated with increased morbidity and mortality. Rates of antibiotic resistance have increased, and resistant species such as methicillin-resistant Staphylococcus aureus provide additional challenges in the form of
virulence factors.
Proteins can disrupt local healing, leading to systemic immune disruption. To optimize outcomes, treatments that reduce pathogenicity must be identified. This study aims to compare a
glycylcycline antibiotic-
tigecycline-with
clindamycin for effectiveness in treating superantigenic methicillin-resistant Staphylococcus aureus in
burn wounds. Methods: Sprague-Dawley rats received paired 2 × 2-cm
burn wounds, which were subsequently inoculated with known
virulence factor-producing methicillin-resistant Staphylococcus aureus or media alone on postinjury day 1. Infected animals received twice-daily
tigecycline (high or low dose), twice-daily
clindamycin (high or low dose), or saline alone (positive controls). Daily sampling and imaging assessments were performed. Results: Bacterial counts and toxin levels were reduced significantly in
antibiotic-treated groups relative to positive controls (P < .001). Results from day 7 showed measurable toxin levels in
clindamycin-treated, but not
tigecycline-treated,
wounds. Imaging analysis revealed a return of
wound perfusion in
tigecycline-treated animals similar to the
sham animals. Transcript analysis using polymerase chain reaction and polymerase chain reaction arrays demonstrated downregulation of gene expression in
antibiotic-treated animals as compared with positive controls. Conclusions: Overall, this study supports the use of
tigecycline in the treatment of methicillin-resistant Staphylococcus aureus-infected
burn wounds. While both
protein synthesis inhibitors are effective,
tigecycline appears to be superior in controlling toxin levels, enabling better wound healing.