What are the treatment guidelines for axillary abscesses?

Treatment Guidelines for Axillary Abscesses

The primary treatment for axillary abscesses is incision and drainage, with antibiotic therapy recommended for complicated cases, especially those with surrounding cellulitis, systemic symptoms, or risk factors for MRSA infection. 1

Initial Management

Surgical Intervention

• Incision and drainage is the cornerstone of treatment for axillary abscesses 1
• For small furuncles, moist heat application may be sufficient to promote drainage 1
• Ultrasound guidance can help distinguish cellulitis from abscess and assist with drainage procedures 2

Antibiotic Selection

For empiric therapy when antibiotics are indicated:

First-line options:

• Trimethoprim-sulfamethoxazole (TMP-SMX): 1-2 DS tablets PO twice daily for 7-14 days 1, 3
• Clindamycin: 300-450 mg PO three times daily for 7-14 days (provides coverage for both MRSA and β-hemolytic streptococci) 1, 3
• Doxycycline: 100 mg PO twice daily (for patients ≥8 years of age) 1

For severe infections requiring IV therapy:

• Vancomycin: IV (dosing based on weight) 1
• Linezolid: 600 mg PO/IV twice daily 1
• Daptomycin: 4 mg/kg/dose IV once daily 1
• Telavancin: 10 mg/kg/dose IV once daily 1

When to Add Antibiotics

Antibiotic therapy should be added to incision and drainage in the following scenarios:

• Extensive or rapidly spreading cellulitis
• Signs of systemic infection (fever, tachycardia)
• Immunocompromised state
• Extremes of age
• Abscess in difficult-to-drain area
• Failed response to incision and drainage alone 1

Special Considerations

MRSA Coverage

• Consider empiric MRSA coverage as community-acquired MRSA (CA-MRSA) is a common cause of axillary abscesses 4
• In areas with high MRSA prevalence, TMP-SMX or clindamycin are preferred options 1, 3

Pediatric Patients

• For children <8 years: avoid tetracyclines 1
• For children with minor skin infections: mupirocin 2% topical ointment can be used 1
• For hospitalized children: vancomycin or clindamycin (10-13 mg/kg/dose IV every 6-8h) 1

Recurrent Infections

For patients with recurrent axillary abscesses, especially those with hidradenitis suppurativa:

• Consider decolonization with intranasal mupirocin and chlorhexidine washes 2
• Radical surgery may be indicated for hidradenitis suppurativa 5
• Metronidazole may help with odorous discharge in hidradenitis suppurativa 5

Duration of Therapy

• Standard treatment duration is 7-14 days 1
• Reassess after 2-3 days to evaluate response 2
• If no improvement after 7 days, consider:
  • Culture and sensitivity testing
  • Alternative antibiotic regimen
  • Reevaluation of diagnosis 2

Treatment Efficacy

Recent high-quality evidence shows that adding antibiotics (clindamycin or TMP-SMX) to incision and drainage significantly improves cure rates compared to incision and drainage alone for smaller abscesses (≤5 cm) 3. In this study:

• Cure rates: Clindamycin (83.1%), TMP-SMX (81.7%) vs. placebo (68.9%)
• Clindamycin showed fewer recurrent infections at 1-month follow-up (6.8%) compared to TMP-SMX (13.5%) or placebo (12.4%)
• However, clindamycin had more adverse events (21.9%) than TMP-SMX (11.1%) or placebo (12.5%) 3

Common Pitfalls and Caveats

• Inadequate drainage: Ensure complete drainage of the abscess cavity
• Missed diagnosis: Consider underlying conditions like hidradenitis suppurativa 5 or rare causes like primary breast lymphoma 6 in non-healing cases
• Pain management: Consider nerve blocks (e.g., axillary nerve block) for effective pain control during drainage procedures 7
• Antibiotic selection: Be aware that TMP-SMX and tetracyclines have limited activity against β-hemolytic streptococci 2
• Follow-up: Ensure appropriate follow-up to assess treatment response and identify recurrences