Acute Rheumatic Fever
Guidelines of diagnosis used by the American Heart Association include major and minor criteria (i.e., Jones criteria). In addition to evidence of a previous streptococcal infection, the diagnosis requires 2 major Jones criteria or 1 major plus 2 minor Jones criteria.
- Carditis occurs in as many as 40% of patients and may include cardiomegaly, new murmur, congestive heart failure, and pericarditis, with or without a rub and valvular disease.
- Arthritis occurs in 75% of cases and is polyarticular, fleeting, and involves large joints, particularly the knees, ankles, elbows and wrists. Characteristically the arthritis migrates from joint to joint over a period of days. Generally the pain is very severe, out of proportion to the degree of objective inflammation of the joint itself.
- Subcutaneous nodules (i.e., Aschoff bodies) occur in 10% of patients and are edematous fragmented collagen fibers. They are firm painless nodules on the extensor surfaces of wrists, elbows, and knees. They generally occur several weeks after the onset of fever, and usually take weeks to resolve.
- Erythema marginatum occurs in about 5% of cases. The rash is serpiginous and long lasting.
- Sydenham chorea (i.e., St. Vitus dance) is a characteristic movement disorder that occurs in 5-10% of cases. Sydenham chorea consists of rapid purposeless movements of the face and upper extremities. Onset may be delayed for several months and may cease when the patient is asleep.
- Clinical findings include arthralgia and fever.
- Laboratory findings include elevated acute phase reactants (e.g., erythrocyte sedimentation rate, C reactive protein), a prolonged PR interval, and supporting evidence of antecedent group A streptococcal infections (i.e., positive throat culture or rapid streptococcal screen and an elevated or rising streptococcal antibody titer).
Antistreptococcal prophylaxis should be maintained continuously after an attack of acute RF (or chorea) to prevent recurrences. Benzathine penicillin G in a monthly IM injection of 1.2 million U is most effective, but the injections are painful and require monthly medical attention. Sulfadiazine, in a single oral dose of 1 g/day (500 mg/day in patients <= 27 kg [<= 60 lb]), is as effective as other oral regimens, including penicillin G 400,000 U divided bid or penicillin V 250 mg divided bid.
The optimum duration of antistreptococcal prophylaxis is uncertain. Some authorities believe prophylaxis should be lifelong in all RF or chorea patients, or as long as they have close contact with children, who have higher rates of carriage of group A streptococci. Others recommend prophylaxis only for the first few years after an acute attack in all patients < 18 yr, and for life only in patients with severe cardiac damage.
In patients with mild cardiac damage (i.e., murmurs but no cardiomegaly or decompensation), prophylaxis can be maintained; if it is discontinued, early treatment of streptococcal infections is required.
American Heart Association -
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