What is the appropriate workup and antibiotic of choice, such as Amoxicillin (amoxicillin), for an individual presenting to the Emergency Room (ER) with a human bite?

From the Guidelines

For a patient presenting to the ER with a human bite, the most appropriate antibiotic of choice is Amoxicillin-Clavulanate (Augmentin) 875/125 mg orally twice daily for 5-7 days for uncomplicated cases, or 10-14 days for established infections, as recommended by the Infectious Diseases Society of America 1. The initial workup for an individual coming to the ER for a human bite should include a thorough history and physical examination, focusing on the time of injury, bite location, and signs of infection.

• Cleaning the wound thoroughly
• Assessing for structural damage
• Obtaining wound cultures if infection is suspected
• Ordering X-rays to evaluate for fractures or foreign bodies, especially for bites over joints or bones
• Laboratory tests including complete blood count and basic metabolic panel to help assess for systemic infection. The choice of antibiotic is crucial due to the diverse range of pathogens involved in human bites, including streptococci, S. aureus, Eikenella corrodens, and multiple anaerobic organisms.
• Amoxicillin-Clavulanate is effective against these pathogens, although it may not cover MRSA or some gram-negative rods 1.
• For penicillin-allergic patients, alternatives such as Clindamycin plus either Trimethoprim-Sulfamethoxazole or a fluoroquinolone can be considered, or a fluoroquinolone like ciprofloxacin or levofloxacin plus metronidazole, or moxifloxacin as a single agent 1.
• Intravenous antibiotics, such as Ampicillin-Sulbactam, may be necessary for severe infections, immunocompromised patients, or hand injuries.
• Tetanus prophylaxis should be updated if needed, and the patient should be assessed for potential HIV or hepatitis exposure risk.
• Close follow-up within 24-48 hours is essential to monitor for developing complications. Given the potential for serious complications, including infection and systemic disease, aggressive treatment and close monitoring are essential for managing human bite wounds effectively, prioritizing morbidity, mortality, and quality of life as outcomes 1.

From the Research

Workup for Human Bite Injuries

• History and examination of the wound to assess the severity and potential for infection 2
• Wound care, including irrigation and debridement to prevent infection 3
• Assessment of risk of disease transmission, including tetanus and hepatitis B 4
• Evaluation of the need for surgical intervention, particularly for clenched fist injuries or avulsive injuries with significant tissue loss 2, 3

Antibiotic Therapy

• The best choice for oral or intravenous antibiotic therapy is a combination of a beta-lactam antibiotic with a beta-lactamase inhibitor, such as amoxicillin-clavulanate 2, 3
• Moxifloxacin is also an option, offering broad-spectrum coverage of the pathogenic flora 3
• Antibiotic therapy should be targeted against the suspected pathogens, including oral and skin flora, such as Streptococcus pyogenes, Eikenella corrodens, and Staphylococcus aureus 3, 5

Management of Human Bite Injuries

• Initial wound management, including irrigation and debridement, is crucial for preventing infection 3
• Primary surgical repair is the treatment of choice for most clinically uninfected facial bite wounds, whereas delayed closure should be reserved for certain high-risk or already infected wounds 3
• Prophylaxis against systemic infectious complications, particularly tetanus, should also be evaluated 3, 4