Management of Erythema Nodosum
For erythema nodosum, nonsteroidal anti-inflammatory drugs (NSAIDs) should be used as first-line treatment, with systemic corticosteroids reserved for severe cases that don't respond to NSAIDs. 1
Clinical Presentation and Diagnosis
Erythema nodosum (EN) is characterized by:
- Tender, raised, red or violet subcutaneous nodules of 1-5 cm in diameter
- Typically affects extensor surfaces of extremities, particularly anterior tibial areas
- Often bilateral and symmetrical
- Usually self-limited and resolves without scarring
- May be accompanied by systemic symptoms including arthralgia and fatigue
Diagnosis is primarily clinical, with biopsy rarely needed except in atypical cases. Histology reveals a non-specific focal panniculitis.
Etiology Assessment
Before initiating treatment, identify potential underlying causes:
- Streptococcal infections (most common identifiable cause)
- Tuberculosis
- Sarcoidosis
- Inflammatory bowel disease
- Medications (oral contraceptives, antibiotics)
- Behçet's disease
- Pregnancy
- Idiopathic (30-50% of cases)
Key diagnostic tests:
- Complete blood count with differential
- Erythrocyte sedimentation rate and/or C-reactive protein
- Streptococcal testing (throat culture, ASO titer)
- Chest radiography
- Additional tests based on clinical suspicion
Treatment Algorithm
First-line Treatment:
- NSAIDs for pain management and inflammation control 1, 2
- Ibuprofen, naproxen, or indomethacin
- Monitor for gastrointestinal side effects 3
For Severe or Refractory Cases:
- Systemic corticosteroids (e.g., prednisone) 1
- Reserved for severe cases not responding to NSAIDs
- Short course with gradual taper to minimize side effects 4
For Specific Etiologies:
- Colchicine is preferred when erythema nodosum is the dominant lesion 1
- Treat underlying conditions:
- Antibiotics for streptococcal or other bacterial infections
- Discontinuation of offending medications
- Appropriate management for inflammatory bowel disease or sarcoidosis
For Resistant Cases:
- Immunomodulators may be considered 1
- Azathioprine
- TNF-alpha antagonists (infliximab, adalimumab)
- Interferon-alpha
Supportive Care
- Bed rest during acute phase
- Elevation of affected limbs to reduce edema and discomfort
- Compression stockings may provide symptomatic relief
- Avoid triggering factors if identified
Monitoring and Follow-up
- Regular assessment of response to treatment
- Monitor for resolution of lesions (typically 2-6 weeks)
- Evaluate for recurrence, which may suggest persistent underlying disease
Important Considerations
- Erythema nodosum is often associated with disease activity in conditions like inflammatory bowel disease 1
- Treatment should focus on the underlying cause when identified
- Systemic corticosteroids provide rapid relief but should be used judiciously due to potential side effects 4
- NSAIDs should be used with caution in patients with gastrointestinal risk factors 3
Prognosis
Most cases of erythema nodosum are self-limited and resolve within 3-6 weeks without scarring. Recurrence may occur, particularly if the underlying cause is not adequately addressed.