Empiric antibiotic therapy for seawater injuries: A four-seasonal analysis

BACKGROUND: Previous seawater studies found Vibrio species associated with morbidity, suggesting that seawater-contaminated wounds should be treated early. The purpose of this study was to identify common seawater pathogens and antibiotic sensitivities to provide empiric antibiotic therapy until patient-specific culture results are available. METHODS: Seasonal samples were collected from 25 Galveston beach locations and cultured. Colonies were identified and sensitivities were performed using MicroScan Positive and Negative Breakpoint Combo Panels. RESULTS: In the fall (28.3°C), of 15 species isolated, the three most common isolates were Escherichia coli, Enterococcus faecium, and Klebsiella pneumoniae. Gram-negative isolates were sensitive to levofloxacin, lomefloxacin, and cefepime. Gram-positive isolates were sensitive to penicillin and ampicillin. In the winter (11.1°C), of 14 species isolated, the three most common isolates were Enterobacter agglomerans, E. faecium, and E. coli. Gram-negative isolates were sensitive to levofloxacin, lomefloxacin, and cefepime. Most Gram-positive isolates were sensitive to vancomycin, levofloxacin, penicillin, and ampicillin. In the spring (26.6°C), of 14 species isolated, the three most common isolates were E. coli, Bacillus species, and E. faecium. Gram-negative isolates were sensitive to levofloxacin, lomefloxacin, and cefepime. Most Gram-positive isolates were sensitive to penicillin, ampicillin, vancomycin, and levofloxacin. In the summer (29.7°C), of 17 bacterial species isolated, the three most common isolates were Bacillus species, Enterobacter cloacae, and K. pneumoniae. Gram-negative isolates were sensitive to cefepime, lomefloxacin, and levofloxacin. Gram-positive isolates were sensitive to penicillin, ampicillin, vancomycin, levofloxacin, and chloramphenicol. CONCLUSIONS: Cultured pathogens were sensitive to penicillin, ampicillin, or levofloxacin. The authors recommend a combination of penicillin or ampicillin with levofloxacin for empiric antibiotic coverage for seawater-contaminated injuries.