What is Erythema Marginatum?

Erythema marginatum is a distinctive skin rash seen in some cases of rheumatic fever, where people develop widespread inflammation in the wake of a streptococcal infection. The rash can be an important diagnostic clue, as well as a warning, and tends to be more likely in children than adults. It consists of a series of circular patches along the torso and the insides of the extremities. The rash does not itch or burn, and it can be difficult to spot in people with dark skin, as the distinctive red flush may be hidden by their natural skin pigmentation.

In erythema marginatum, the rash starts as a patch and grows outward in a circular fashion. As the rash spreads, the middle tends to clear. This creates a series of red, slightly raised rings. Some of them can be quite large. Usually the face and the outward parts of the extremities, like the hands and the fronts of the legs, will not develop the rash. Patients will notice that it tends to redden in response to heat, like after a shower or in very warm weather.

Treatment of erythema marginatum requires addressing the underlying rheumatic fever. Antibiotics are available to kill the bacteria, and patients may also be given anti-inflammatory drugs. Patients can also sometimes benefit from applications of soothing creams and other preparations to the skin, to reduce the swelling and redness of the rash. Simply applying moisturizer after a shower can be very helpful for reducing skin irritation and minimizing the appearance of the rash.

The erythema marginatum rash is a symptom, rather than a primary disease, and treatment will be focused on the source of the rash rather than the rash itself. It may persist for months in some patients, even after the rheumatic fever has been addressed. Treating rheumatic fever is important, as it can damage the heart and lead to heart problems later in life. Patients who are not treated may die as a result of injuries to the heart muscle caused by the inflammation.

People who notice erythema marginatum along with joint pain and fever should be evaluated for rheumatic fever, especially if they have a recent history of strep infection. The earlier treatment is provided, the more effective it will be. Rapid treatment also preempts some of the complications of the disease and can help patients enjoy a longer, healthier life after recovery from rheumatic fever.