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 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

A study of children in India reported the rash in only 4 of 250.⁴ Another study from India looked especially at children under 5. They found that two thirds of patients with a first attack were between 5 and 15 years old and only 6.8% were under 5. Of those 28 patients, none had erythema marginatum.⁵ Although the disease is common in India and other developing countries, it may be surprising to find a study of 541 cases of rheumatic fever seen from 1985 to 2000 in the USA.⁶ The paper came from Salt Lake City in Utah that is the home of the Mormons (Church of the Latter Day Saints) but they are not a sect who reject medicine. They found that 5% of patients were under 5 and that erythema marginatum was more likely in the younger age group.

Most doctors in general practice in Great Britain will never see a case in their entire lives. When Clinical Evidence examined the prescription of antibiotics for sore throat, they found 111 cases of acute rheumatic fever assessed by the review. All occurred in 10 trials undertaken between 1950 and 1961. There were no cases in the remaining five trials undertaken between 1987 and 2000.⁷

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. 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.

It is shown well in the picture at Ref 8.⁸

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

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.⁹

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.

As for rheumatic fever.