What is the recommended antibiotic treatment for a large axillary abscess that has been drained in the Emergency Room (ER)?

From the Guidelines

For an axillary abscess that has been drained in the ER, empiric antibiotic therapy should include coverage for MRSA and streptococcal species, with the recommended first-line treatment being trimethoprim-sulfamethoxazole (TMP-SMX) 1-2 double-strength tablets (160mg/800mg) twice daily for 5-10 days, as supported by the Infectious Diseases Society of America guidelines 1.

Key Considerations

• The primary treatment for abscesses is incision and drainage, with antibiotics playing an adjunctive role 1.
• Empiric antibiotic therapy should cover both MRSA and streptococcal species, with options including TMP-SMX, clindamycin, doxycycline, and linezolid 1.
• The duration of therapy depends on clinical response, with most uncomplicated cases requiring 5-7 days of treatment after successful drainage 1.
• Patients should be instructed to keep the wound clean and dry, change dressings as directed, complete the full antibiotic course even if symptoms improve, and return for follow-up in 48-72 hours to ensure proper healing.

Antibiotic Options

• TMP-SMX: 1-2 double-strength tablets (160mg/800mg) twice daily for 5-10 days 1.
• Clindamycin: 300-450mg orally four times daily for 5-10 days 1.
• Doxycycline: 100mg twice daily for 5-10 days 1.
• Linezolid: 600mg twice daily for 5-10 days 1.

Special Considerations

• If MRSA is less likely and traditional skin flora more probable, cephalexin 500mg four times daily or dicloxacillin 500mg four times daily for 5-10 days may be appropriate 1.
• The choice of antibiotic should be reassessed if culture results become available, as targeted therapy based on susceptibility testing is optimal for preventing recurrence and ensuring complete resolution 1.

From the FDA Drug Label

DOSAGE AND ADMINISTRATION Usual Adult Dosage *In rare instances, doses of up to 12 grams of cefazolin per day have been used Type of InfectionDoseFrequency Moderate to severe infections 500 mg to 1 gram every 6 to 8 hours For the treatment of a large axillary abscess that has been drained, moderate to severe infection dosage is applicable.

• The recommended dose for moderate to severe infections is 500 mg to 1 gram every 6 to 8 hours.
• Given the context of the question, the most suitable choice of antibiotic from the provided options would be cefazolin (IV) at a dose of 500 mg to 1 gram every 6 to 8 hours 2.

From the Research

Antibiotic Treatment for Large Axillary Abscess

• The treatment of large axillary abscesses typically involves incision and drainage (I&D) in the emergency room (ER), and the use of antibiotics may be considered in certain cases 3.
• For methicillin-resistant Staphylococcus aureus (MRSA) infections, vancomycin and daptomycin are commonly used antibiotics 4, 5, 6.
• However, for methicillin-susceptible Staphylococcus aureus (MSSA) infections, nafcillin or cefazolin may be more effective than vancomycin, with lower mortality hazards 7.
• The decision to use antibiotics should be based on the presence of high-risk features, such as immunocompromised status, and the results of wound cultures 3.
• It is essential to note that the use of antibiotics should be guided by antibiotic susceptibility results, and empirical treatment should include coverage for MRSA until susceptibility results are available 5, 6.

Considerations for Antibiotic Treatment

• The choice of antibiotic should be based on the suspected or confirmed causative organism, as well as the patient's individual risk factors and medical history 4, 5, 6.
• Vancomycin and daptomycin are options for the initial treatment of MRSA bacteremia, while nafcillin or cefazolin may be used for MSSA infections 4, 5, 7.
• Combination therapies and alternative antibiotics, such as ceftaroline, may be considered for persistent MRSA bacteremia or bacteremia due to vancomycin-intermediate or vancomycin-resistant strains 6.
• Source control, including removal of infected devices and drainage of abscesses, is a critical component of treating Staphylococcus aureus bacteremia 5.