Treatment Options for Erysipelas versus Cellulitis
For erysipelas, penicillin V is the first-line treatment, while cellulitis should be treated with cephalexin or dicloxacillin as first-line options, with both conditions typically requiring 5-7 days of therapy. 1
Distinguishing Features
Erysipelas
- Superficial infection affecting upper dermis and lymphatics
- Primarily caused by beta-hemolytic streptococci (usually Streptococcus pyogenes)
- Well-demarcated, raised borders with fiery red appearance
- Typically affects the face and lower extremities 1, 2
Cellulitis
- Deeper infection affecting dermis and subcutaneous tissue
- Primarily caused by streptococci, but may involve Staphylococcus aureus
- Less defined borders with more diffuse appearance
- More commonly affects the lower extremities 1
Antibiotic Treatment Recommendations
Erysipelas Treatment
- First-line: Penicillin V (oral)
- Alternatives: Erythromycin, clindamycin
- Duration: 5-7 days 1
Research supports penicillin's effectiveness for erysipelas, with one study showing shorter fever duration after treatment initiation compared to non-penicillin regimens (1.7 vs. 4.5 days) 2
Cellulitis Treatment
- First-line: Cephalexin or dicloxacillin
- Alternatives: Clindamycin, amoxicillin-clavulanate
- Duration: 5-7 days 1
Treatment Considerations
Route of Administration
- Mild to moderate cases: Oral antibiotics
- Severe cases: Parenteral (IV) antibiotics 1
- Interestingly, some research suggests oral macrolides can be more effective than IV penicillin in certain situations 3
MRSA Coverage
- Add MRSA coverage if:
- History of MRSA colonization
- Previous MRSA infection
- No response to beta-lactam therapy 1
S. aureus Coverage Controversy
Recent research questions whether empirical coverage of S. aureus is necessary for most cases of cellulitis/erysipelas, suggesting streptococci are responsible for the vast majority of cases. However, more definitive trials comparing penicillin monotherapy to S. aureus-covering regimens are needed 4.
Adjunctive Measures
- Elevate affected area to promote drainage of edema and inflammatory substances 1
- Perform incision and drainage for any associated abscess 1
- Apply elastic compression for leg edema from venous or lymphatic origin 5
Prevention of Recurrence
- Address predisposing factors:
- Interdigital maceration
- Skin hydration
- Underlying edema 1
- Prophylactic antibiotics for frequent recurrences:
- Monthly intramuscular benzathine penicillin
- Oral penicillin V
- Oral erythromycin 1
Pitfalls in Prophylaxis
Even with prophylactic antibiotics, recurrences can occur due to:
- Noncompliance
- Incorrect antibiotic selection
- Insufficient dosing
- Non-streptococcal pathogens 6
Monitoring Response
- Assess clinical improvement within 72 hours
- Look for:
- Decreasing erythema, warmth, and swelling
- Resolution of fever and systemic symptoms
- Improvement in pain 1
If no improvement after 72 hours:
- Reevaluate diagnosis
- Consider drainage if abscess is present
- Change antibiotic therapy 1