Treatment of Cellulitis with an Abscess
The primary treatment for cellulitis with an abscess is incision and drainage of the abscess, followed by antibiotic therapy when specific indications are present such as significant surrounding cellulitis, systemic symptoms, or immunocompromised state. 1, 2
Initial Management
Surgical Intervention
- Incision and drainage (I&D) is the cornerstone of treatment for all abscesses
- For large abscesses, use multiple counter incisions rather than a single long incision to prevent delayed wound healing 1
- Loop drainage technique is preferred over traditional I&D for better outcomes 3
Antibiotic Therapy Indications
Antibiotics should be added to I&D when:
- Systemic signs of infection are present (fever, elevated WBC)
- Patient is immunocompromised
- Source control is incomplete
- Significant cellulitis surrounds the abscess
- Abscess is in a difficult-to-drain area
- Patient has failed to respond to I&D alone 1, 2
Antibiotic Selection
For Simple Cellulitis with Abscess
If MRSA is not suspected:
- Oral beta-lactams (e.g., cephalexin) for mild cases
- Parenteral beta-lactams for more severe cases 1
If MRSA is suspected or prevalent in your area:
- Trimethoprim-sulfamethoxazole (TMP-SMX): 1-2 double-strength tablets (160/800 mg) twice daily
- Clindamycin: 300-450 mg orally four times daily
- Doxycycline: 100 mg twice daily
- Linezolid: 600 mg orally twice daily (for severe cases) 2
For Complex Abscesses
- Empiric broad-spectrum antibiotic therapy covering Gram-positive, Gram-negative, and anaerobic bacteria is recommended 1
- For severe infections requiring IV therapy:
Treatment Duration
- Uncomplicated infections: 5-10 days
- Complicated infections: 14-21 days 2
- Switch from IV to oral therapy when clinical improvement occurs (typically after 2-3 days) 2
Special Considerations
Perianal and Perirectal Abscesses
- Require prompt surgical drainage
- Broad-spectrum antibiotics covering anaerobes are essential when cellulitis is present 1
Intravenous Drug Users
- Consider potential for unusual pathogens
- Evaluate for endocarditis if persistent signs of systemic infection
- Rule out foreign bodies (broken needles) with radiography
- Perform duplex sonography to identify vascular complications
- Screen for viral infections (HIV, HCV, HBV) 1
Indications for Hospitalization
- Extensive or rapidly spreading erythema
- Systemic symptoms (high fever, significant leukocytosis)
- Facial or periorbital involvement
- Failure of oral antibiotics
- Immunocompromised state
- Age less than 3 months
- Inability to tolerate oral medications 2
Evidence-Based Outcomes
Recent research has demonstrated that for smaller abscesses (≤5 cm), antibiotics after I&D significantly improve cure rates compared to I&D alone. A placebo-controlled trial showed that clindamycin or TMP-SMX in conjunction with I&D improved short-term outcomes, with cure rates of 83.1% and 81.7% respectively, compared to 68.9% with placebo 5.
Common Pitfalls to Avoid
- Inadequate surgical drainage
- Using fluoroquinolone monotherapy for staphylococcal infections
- Assuming beta-lactam/beta-lactamase inhibitor combinations will cover MRSA
- Failing to consider local resistance patterns
- Using vancomycin in patients with renal impairment without appropriate monitoring 2
By following this evidence-based approach to managing cellulitis with abscess, you can optimize patient outcomes while minimizing complications and recurrence.