Management of Erythema Nodosum
For erythema nodosum, first-line treatment consists of NSAIDs, with systemic corticosteroids reserved for severe cases that don't respond to initial therapy. 1
Diagnosis and Etiology
- Erythema nodosum (EN) is characterized by raised, tender, red or violet subcutaneous nodules, typically 1-5cm in diameter
- Most commonly affects the extensor surfaces of extremities, particularly anterior tibial areas
- Diagnosis is primarily clinical; biopsy is rarely needed except in atypical cases
- Often associated with systemic symptoms including arthralgia and fatigue
Common Underlying Causes
- Inflammatory bowel disease
- Streptococcal infections
- Sarcoidosis
- Tuberculosis
- Medications (including oral contraceptives)
- Histoplasmosis
- Behçet's disease
- Often idiopathic (no identifiable cause)
Treatment Algorithm
Step 1: Address Underlying Cause
- Identify and treat any underlying condition (e.g., antibiotics for streptococcal infection)
- Discontinue any potentially causative medications
Step 2: First-Line Therapy
- NSAIDs (2-12 weeks based on clinical resolution) 1
- Options include ibuprofen, naproxen, indomethacin
- Aspirin may also be effective
- Continue until symptoms resolve
Step 3: For Inadequate Response to NSAIDs
- Systemic corticosteroids for severe cases 1
- Prednisone: Initial suppressive dose (typically 0.5-1 mg/kg/day) for 4-10 days
- Then taper to lowest effective dose
- Consider alternate-day therapy to minimize side effects 2
Step 4: Additional Options for Refractory Cases
- Colchicine (1-2 mg/day) - particularly effective for EN associated with Behçet's disease 3
- Potassium iodide may help enhance resolution 4
- For recurrent cases, consider immunomodulators (azathioprine, infliximab, adalimumab) 1
Supportive Care Measures
- Elevation of affected area to reduce edema
- Bed rest during acute phase
- Avoid prolonged standing
- Compression stockings may help with associated edema
Important Considerations
Efficacy of Treatment
- Most cases are self-limiting and resolve within 3-6 weeks
- NSAIDs primarily provide symptomatic relief while the condition resolves
- Systemic corticosteroids can provide rapid improvement but should be used judiciously
Cautions
- Avoid prolonged corticosteroid use due to potential side effects
- Ensure tuberculosis is ruled out before starting corticosteroids
- NSAIDs may be contraindicated in patients with certain comorbidities (renal disease, peptic ulcer disease)
Follow-up
- Monitor for resolution of symptoms
- Assess for recurrence which may indicate persistent underlying disease
- For recurrent cases, consider more extensive evaluation for systemic diseases
EN is typically a self-limiting condition with good prognosis. While symptomatic treatment with NSAIDs is usually sufficient, addressing any underlying cause is crucial for preventing recurrence and improving long-term outcomes.