Erythema nodosum is an inflammatory disorder. In many cases, the cause is unknown. In some cases, it may be caused by strep or other infections.
Symptoms include flat, firm, hot, red, painful lumps that usually appear on the shins. Later, they may fade and look more like a bruise and then resolve on their own.
The underlying infection or condition needs treatment. Medications can treat the rash.
Last Updated Jun 13, 2017