erythema nodosum


Erythema nodosum is the most common form of panniculitis, or inflammation of the fat. Erythema nodosum manifests as ill-defined, tender, bilateral dermal red or violaceous nodules, most commonly on the bilateral shins. Most resolve spontaneously over 4 to 6 weeks. Erythema nodosum is a nonspecific reaction to some systemic process.

Erythema nodosum manifests as painful, red-brown nodules on the anterior shins.

The most common associations are streptococcal infection, hormones (including oral contraceptives, hormone replacement therapy, or pregnancy), inflammatory bowel disease, sarcoidosis, and other medication reactions. The appearance of erythema nodosum in patients with sarcoidosis usually signifies an acute presentation with a good long-term prognosis. The combination of erythema nodosum, arthritis, hilar lymphadenopathy, and fevers constitute Löfgren syndrome. This set of findings is so specific for sarcoidosis that a biopsy is not needed to confirm the diagnosis. Most cases of erythema nodosum resolve spontaneously, and therapy is supportive in nature with NSAIDs and compression stockings.

The diagnosis of EN can be clinically based on the acute onset of tender nodules on the bilateral shins typically in a young woman. Biopsy is not necessary in typical lesions.

Most authorities recommend a chest radiograph in the evaluation of EN to assess for the presence of lymphoma, sarcoidosis, tuberculosis, and fungal infection such as coccidioidomycosis.

In the absence of gastrointestinal symptoms, a colonoscopy for inflammatory bowel disease is unlikely to reveal a causative diagnosis. Patients with disseminated gonococcal infection and bacteremia manifest vesiculopustular or hemorrhagic macular skin lesions, not tender subcutaneous nodules as seen in this patient.1

  • tender nodules on the skin

Footnotes

  1. Cutaneous Manifestations of Internal Disease