Dog bite wounds and infection: a prospective clinical study

Area of Science:

• Emergency Medicine
• Infectious Diseases
• Wound Care

Background:

• Dog bite wounds are common injuries presenting to emergency departments.
• Understanding patient concerns and wound bacteriology is crucial for effective management.

Purpose of the Study:

• To investigate the distinct patient populations presenting with dog bite wounds based on time post-injury.
• To analyze the bacteriology of dog bite wounds.
• To evaluate the effectiveness of empiric antibiotic therapy.

Main Methods:

• Prospective study of 26 patients with 27 dog bite wounds.
• Categorization of patients based on presentation time (8-12 hours vs. >12 hours post-injury).
• Bacteriological analysis of wound swabs, including aerobic and anaerobic pathogens.
• Assessment of Gram stain utility.
• Evaluation of outpatient antibiotic therapy (penicillin and/or dicloxacillin).

Main Results:

• Two distinct patient populations emerged: those presenting 8-12 hours post-injury (concerned with rabies, tetanus, or surgical repair) and those presenting >12 hours post-injury (concerned with infection).
• No significant difference in wound bacteriology was observed between the two groups (P > 0.05).
• Aerobic pathogens were isolated from 74% of wounds (e.g., Streptococcus viridans, Staphylococcus aureus, Pasteurella multocida).
• Anaerobic pathogens were isolated from 41% of wounds (e.g., Bacteriodes, Fusobacterium).
• Gram stains were specific but insensitive for predicting bacterial growth.
• Empiric outpatient therapy with oral penicillin and/or dicloxacillin was effective.

Conclusions:

• Patient concerns regarding dog bite wounds vary based on presentation time.
• Dog bite wounds harbor a significant load of both aerobic and anaerobic bacteria.
• Empiric antibiotic treatment with penicillin and/or dicloxacillin is an effective strategy for managing dog bite wounds.