Treatment of Erythema Nodosum
The first-line treatment for erythema nodosum is to identify and treat the underlying cause, while managing symptoms with NSAIDs such as acetylsalicylic acid, ibuprofen, naproxen, or indomethacin for 2-12 weeks based on clinical resolution. 1
Diagnostic Evaluation
Before initiating treatment, a thorough diagnostic workup is essential to identify potential underlying causes:
- Complete blood count with differential
- Erythrocyte sedimentation rate and/or C-reactive protein
- Testing for streptococcal infection (throat culture, rapid antigen test)
- Chest radiograph
- Additional testing based on clinical suspicion of specific causes 1, 2
Treatment Algorithm
1. Treat the Underlying Cause
Erythema nodosum is often associated with:
- Streptococcal infections (most common cause in children)
- Sarcoidosis (common in adults)
- Inflammatory bowel disease
- Tuberculosis
- Medications (including oral contraceptives)
- Other systemic diseases 1, 3, 2
2. Symptomatic Treatment
First-Line Therapy:
- NSAIDs for pain and inflammation management
For Recurrent or Resistant Cases:
- Colchicine is recommended as first-line treatment for recurrent cases, particularly when associated with Behçet's disease or inflammatory bowel disease 1
For Severe Cases Unresponsive to First-Line Therapy:
- Systemic corticosteroids may be considered
- Use brief courses to minimize side effects
- Not generally recommended for routine use due to the self-limited nature of the disease 1
For Resistant Cases or Frequent Relapses:
- Immunomodulators such as azathioprine or TNF-α antagonists (infliximab, adalimumab) may be considered 1
3. Supportive Care Measures
- Rest and elevation of affected limbs
- Compression stockings to reduce edema
- Avoidance of prolonged standing or sitting
- Adequate pain management 1
Special Considerations
Pregnancy
Pregnancy can create an optimal background for erythema nodosum to develop. Treatment options must be carefully selected, and consultation with an obstetrician is essential before prescribing medications 4.
Contraindications and Cautions
- NSAIDs may be contraindicated in patients with peptic ulcer disease or renal impairment
- Systemic steroids should be avoided when an underlying infection hasn't been ruled out 1
Monitoring and Follow-up
- Regular assessment of treatment response
- Monitoring for recurrence after treatment discontinuation
- Evaluation for signs of underlying disease progression 1
Common Pitfalls to Avoid
Misdiagnosis: Erythema nodosum is commonly confused with cellulitis, infected insect bites, or minor trauma, especially in emergency settings 1
Failure to identify underlying causes: Always investigate for systemic diseases, as erythema nodosum may be the first sign of conditions like tuberculosis, sarcoidosis, or inflammatory bowel disease 2
Overuse of corticosteroids: While effective, systemic steroids should be reserved for severe cases unresponsive to first-line therapy due to potential side effects 1, 3
Inadequate treatment duration: Relapse may occur after discontinuation, requiring reinstitution of therapy for another 4-8 weeks 1