Erythema Marginatum

Erythema marginatum is a rash that is associated with acute rheumatic fever and sometimes called erythema marginatum rheumatica. Rheumatic fever is a multisystem disease that occurs after infection with a Lancefield group A streptococcus.

The rash represents one of the major Jones criteria¹ for the diagnosis of rheumatic fever. The Jones criteria date back to 1944 but were modified in 1992.²

The term erythema annulare is sometimes used for erythema marginatum but Erythema Annulare Centrifugum (see our dedicated record) is classified as one of the figurate or gyrate erythemas. It may be due to a hypersensitivity to malignancy, infection, drugs, or chemicals, or it may be idiopathic. Erythema marginatum is really, by definition, associated with rheumatic fever.

In developed countries, rheumatic fever has become very rare and this rash occurs in no more than 2 to 5% of cases of rheumatic fever. However, rheumatic fever has become as common in New Zealand as in some developing countries, especially amongst the Maori children. In the 1990s there appeared to be a resurgence of rheumatic fever in the USA.³ Erythema marginatum was uncommon in patients with rheumatic fever reported in a large series from Pittsburgh.⁴

Most doctors in general practice in Great Britain will never see a case of rheumatic fever and the likelihood of seeing a case of erythema marginatum is even less.⁵

There are light pink macules spreading outwards with a serpiginous, well-demarcated edge and clearing central portion. The rash changes from hour to hour and may seem to appear, disappear or move so rapidly that it can almost be seen doing so. It often involves multiple areas, usually on the trunk and occasionally over the proximal parts of the limbs. It is exacerbated by heat and fades when the patient is cool.

There are usually other symptoms of acute rheumatic fever but it can recur intermittently over weeks or even months.

It may appear with subcutaneous nodules which are firm, painless lumps, mainly on the hands, feet, occiput and back.⁶ They are usually 0.5 to 2cm in diameter and often found in crops of about 3, appearing 2 to 3 weeks after the onset of fever. The rash occurs early in the disease and remains long past the resolution of other symptoms.

Consider drug reactions. It may look like urticaria that can also change quite rapidly but in erythema marginatum there is no pruritus.

Confirmation of diagnosis of acute rheumatic fever is by:

• Throat swab grows Lancefield group A beta haemolytic streptococcus.
• Rapid antigen test.
• Raised or increasing streptococcal antibody titre.
• In uncertain cases, skin biopsy may allow early diagnosis.⁷

It may be associated with carditis, arthritis, fever and Sydenham's chorea.

There is no specific management of the rash but rheumatic fever must be treated as described in that article. If the diagnosis is suspected it is wise to start a full course of penicillin as for rheumatic fever.

There are no specific complications of the rash but complications such as cardiac disease and Sydenham's chorea may occur as a result of the rheumatic fever.

As for Rheumatic Fever (see our dedicated record).

As for rheumatic fever.