From the Guidelines
Erythema nodosum should be treated based on the underlying inflammatory bowel disease (IBD) with systemic corticosteroids required in severe cases, as stated in the European evidence-based consensus on extra-intestinal manifestations in inflammatory bowel disease 1.
Key Points
- Erythema nodosum is a painful inflammatory condition characterized by tender, red nodules typically appearing on the shins.
- It represents a delayed hypersensitivity reaction that occurs in response to various triggers including infections, medications, inflammatory bowel disease, sarcoidosis, or pregnancy.
- Treatment primarily focuses on addressing the underlying cause while managing symptoms.
- For IBD-associated erythema nodosum, treatment is based on that of the underlying IBD, with systemic corticosteroids may be required in severe cases, as recommended by the European evidence-based consensus on extra-intestinal manifestations in inflammatory bowel disease 1.
- In resistant cases or when there are frequent relapses, immunomodulation with azathioprine, infliximab, or adalimumab may be used, as suggested by the European evidence-based consensus on extra-intestinal manifestations in inflammatory bowel disease 1 and the second European evidence-based consensus on the diagnosis and management of ulcerative colitis 1.
Management
- Systemic corticosteroids, such as prednisone, are recommended in severe cases 1.
- Immunomodulators, such as azathioprine, infliximab, or adalimumab, may be used in resistant cases or frequent relapses 1.
- Evaluation for underlying conditions, such as IBD, infections, or medications, is essential for proper management.
- Patients should be monitored for disease activity and adjusted treatment accordingly.
From the Research
Definition and Characteristics of Erythema Nodosum
- Erythema nodosum is the most frequent clinico-pathological variant of the panniculitides, characterized by inflammatory, tender, nodular lesions, usually located on the anterior aspects of the lower extremities 2.
- The disorder is a cutaneous reaction consisting of tender, erythematous, warm nodules and raised plaques usually located on the shins, ankles, and knees, often bilaterally distributed 2, 3.
- The typical eruption consists of a sudden onset of symmetrical, tender, erythematous, warm nodules, which may become livid red or purplish, and finally exhibit a yellow or greenish appearance 2.
Associated Conditions and Causes
- Erythema nodosum may be associated with a wide variety of diseases, including infections, sarcoidosis, rheumatologic diseases, inflammatory bowel diseases, medications, autoimmune disorders, pregnancy, and malignancies 2, 4.
- The most common identifiable causes are streptococcal infections, primary tuberculosis, sarcoidosis, Behçet disease, inflammatory bowel disease, drugs, and pregnancy 3.
- In approximately 50% of cases, the condition is idiopathic 5.
Histopathology and Diagnosis
- Histopathologically, erythema nodosum is the stereotypical example of a mostly septal panniculitis with no vasculitis, characterized by thickened septa of subcutaneous fat and variously infiltrated by inflammatory cells 2, 4.
- The diagnosis is mainly clinical, with biopsy reserved for atypical cases, and laboratory screening studies may include a complete blood cell count, erythrocyte sedimentation rate, and/or C-reactive protein 5.
Treatment and Management
- Treatment of erythema nodosum should be directed to the underlying associated condition, if identified 2, 4.
- Most cases of erythema nodosum are self-limited and require no treatment, with bed rest and leg elevation recommended to reduce discomfort, and nonsteroidal anti-inflammatory drugs used for pain management 6, 5.
- Systemic corticosteroids are rarely indicated in erythema nodosum and should be used with caution, as they may be contraindicated in certain underlying conditions 2, 6.