From the Guidelines
For a rat bite, immediate cleaning with soap and water for at least 15 minutes is essential, followed by application of an antiseptic like povidone-iodine or hydrogen peroxide, and prompt medical attention is required to assess the need for antibiotics such as amoxicillin-clavulanate (875/125 mg twice daily) as recommended by the Infectious Diseases Society of America 1.
Key Considerations
- Rat bites carry infection risks including rat-bite fever and tetanus, emphasizing the need for prompt medical evaluation 1.
- The choice of antibiotic should cover a broad spectrum of bacteria, including Streptobacillus moniliformis and Spirillum minus, which can cause rat-bite fever 1.
- Amoxicillin-clavulanate is recommended for animal bites, including rat bites, due to its effectiveness against a wide range of pathogens, although it may not cover MRSA 1.
Treatment Approach
- Immediate wound cleaning and application of an antiseptic are crucial steps in preventing infection.
- Assessment of tetanus vaccination status and administration of a booster if necessary are important preventive measures.
- Debridement may be required for wounds with extensive tissue damage.
- Monitoring for signs of infection, such as increasing pain, redness, swelling, or discharge, is vital for early detection and treatment of potential complications.
Antibiotic Selection
- Amoxicillin-clavulanate (875/125 mg twice daily) is a recommended antibiotic for rat bites due to its broad-spectrum coverage, including activity against Pasteurella multocida, streptococci, and anaerobes, although resistance patterns should be considered 1.
- Alternative antibiotics, such as doxycycline, may be considered based on specific patient factors and local resistance patterns 1.
From the Research
Treatment Recommendations for Rat Bites
- The primary concern with rat bites is the risk of infection, particularly with Streptobacillus moniliformis, which can cause rat-bite fever 2, 3.
- Symptoms of rat-bite fever include fever, headache, nausea, myalgia, and rash, and can develop within ten days of the bite 2.
- First-line therapy for rat-bite fever is penicillin, or tetracycline in cases of intolerance 2.
- Surgical cleansing of the infection site in combination with rational antibiotic therapy, such as beta-lactam antibiotics, can cure the infection if treatment is started early enough 3.
- Vaccinations against tetanus and rabies should also be considered, as with all other bite wound infections 3.
- Prophylactic antimicrobial treatment may be debatable, but given the deep puncturing nature of rodent bites, it is suggested that they should be considered a high risk for infection 4.
- Antibiotics selected should include coverage for a broad range of bacterial species, including Staphylococcus aureus, which is a common isolate in rat bite wounds 4, 5.
- Good surgical management and avoidance of prophylactic antibiotics due to a low natural infection rate are also recommended, unless the wound becomes infected 5.
- Tetanus prophylaxis is mandatory, as most patients are deficient in this regard 5.