Erythema Nodosum

A mildly painful, nonpruritic rash on the forearms and legs prompted a 42-year-old man to go to the emergency department (ED). The patient noted the rash when he awoke that morning. He had had joint pain and fever for the past 7 days and generalized malaise with chills that began about 3 days earlier.

He had no significant medical history. In the ED, the patient was afebrile; his blood pressure was 130/85 mm Hg; respiration rate, 16 breaths per minute; and heart rate, 96 beats per minute. He complained of chills but denied headache, visual changes, nausea, vomiting, constipation, diarrhea, abdominal pain, and recent insect bites. He had no history of recent travel or new medications. The day before his ED visit, the patient had been seen by his primary care physician, who ordered laboratory tests. The patient’s erythrocyte sedimentation rate was slightly elevated; antinuclear antibody (ANA) and uric acid levels were normal. Tests for Lyme disease, Epstein-Barr virus infection, and active Mycoplasma infection were negative.

When Robert Levine, DO, of Long Beach, NY, examined the patient at the hospital, he noted large, painful, subcutaneous nodules with overlying erythema on the distal upper and lower extremities and ankle and wrist edema. He admitted the patient and sought cardiology, infectious disease, and rheumatology consultations. The cardiologist initially suspected infectious endocarditis; however, a 2-dimensional echocardiogram showed no obvious valvular vegetations.

A hepatitis profile and blood cultures were negative. Levels of ANA, rheumatoid factor, C3, and C4 were normal. Angiotensin-converting enzyme levels were elevated. A chest radiograph revealed bilateral hilar lymphadenopathy that pointed to a diagnosis of sarcoidosis. Erythema nodosum is an acute inflammatory/immunologic reaction pattern of the panniculus. The most common causes are infections (eg, tuberculosis, histoplasmosis, β-hemolytic streptococcus infection, coccidioidomycosis, and leprosy); reactions to pharmacologic agents (eg, sulfonamides and oral contraceptives); sarcoidosis; ulcerative colitis; and Behçet syndrome. The cause is idiopathic in about 40% of cases.¹

Treatment is mainly symptomatic. Anti-inflammatory agents such as NSAIDs and salicylates have shown some benefit. Systemic corticosteroids are helpful, but only when the cause is known and infectious agents are ruled out.¹ This patient was treated with bed rest and ibuprofen as needed for breakthrough pain and chills. He was discharged with instructions to increase his fluid intake and to schedule a follow-up visit with his primary care physician, who would coordinate long-term treatment of sarcoidosis. Prednisone was started at 20 mg/d and then tapered (5 mg every 2 weeks) over 8 weeks.

The rash and symptoms resolved within 6 to 8 weeks.