Erythema nodosum, idiopathic
Other Names for this Disease
- Idiopathic erythema nodosum
- Erythema nodosum of unknown etiology
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 The lesions begin as firm, hot, red, painful lumps and progress to a purplish color. EN is a type of inflammatory disorder affecting the layer of fat under the skin (panniculitis). Other symptoms that may accompany the skin findings include the following: fever, a general feeling of being ill. joint aches, and swelling of the affected area. In many cases, EN is presumed to be a delayed reaction to antigens associated with various infections, drugs, and certain systemic diseases. In many cases, however, EN has no identifiable cause (idiopathic); in these cases, clinical follow-up is needed to rule out certain conditions including inflammatory bowel disease, sarcoidosis, lymphoma, and Behcet's disease. Treatment may include rest, nonsteroidal anti-inflammatory drugs (NSAIDS), steroids, hot or cold compresses, potassium iodide solution, and supportive bandages or compression stockings. Symptoms usually resolve within six weeks, but EN may become a chronic disorder lasting for months and, occasionally, for years. Approximately 30% cases of idiopathic EN may last more than 6 months.Erythema nodosum (EN) is a skin condition in which red bumps (nodules) form on the shins. Less commonly, the nodules form on other areas of the body such as the thighs and forearms.
Last updated: 9/24/2015
- Erythema nodosum. MedlinePlus. October 18, 2013; https://www.nlm.nih.gov/medlineplus/ency/article/000881.htm. Accessed 9/24/2015.
- Erythema nodosum. DermNet New Zealand Trust. August 1, 2015; http://www.dermnetnz.org/vascular/erythema-nodosum.html. Accessed 9/24/2015.
- Shojania, Kaveh. Erythema nodosum. UpToDate. November 27, 2013; http://www.uptodate.com/contents/erythema-nodosum. Accessed 9/24/2015.
- Hebel, Jeanette. Erythema Nodosum. Medscape Reference. April 13, 2015; http://emedicine.medscape.com/article/1081633-overview. Accessed 9/24/2015.
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