RHEUMATIC FEVER



Rheumatic fever usually occurs in children 5 to 15 years of age. It is caused by group A beta hem­olytic streptococcal pharyngitis that occurs one to three weeks prior to the clinical manifestations of rheumatic fever. It is believed that an immune re­sponse to the Streptococcus is responsible for the disease. Males and females are equally affected. It is more common in patients of lower socio­economic level. The incidence of rheumatic fever in the United States has declined in recent years.

Aschoff nodules in the myocardium are the characteristic pathological feature of rheumatic fever. The most serious manifestation of rheu­matic fever is a pancarditis that may involve the endocardium, myocardium, and pericardium. Usually the mitral valve, less frequently the aor­tic, and even less frequently the tricuspid valve are involved. Pulmonic valve involvement is ex­tremely rare. Valvulitis is recognized by a new insufficiency murmur. Aortic and mitral stenosis murmurs are not heard acutely. Myocarditis may present with heart failure. Pericarditis may pro­duce a friction rub, and the PR interval may pro­long. Because of the difficulty in diagnosing rheumatic fever, guidelines (modified Jones criteria) for establishing the diagnosis were developed (Table 5-4).
Penicillin should be administered to eradicate streptococcal infection. Salicylates are effective rapidly ior treating fever and arthritis but proba­bly have no effect on carditis. The usefulness of steroids is unproven. Congestive heart failure is treated traditionally.
The relatively high recurrence rate of rheumatic fever after streptococcal infection continues for at least 5 to 10 years after the initial infection; there­fore, rheumatic fever prophylaxis should be dis­continued only in adults 5 to 10 years after the acute episode and only then if the risk of the strep­tococcal infection is low. Adults working with school-age children, those in the military service, those exposed to large numbers of people, and those in the medical or allied health professions should receive prophylaxis indefinitely. Patients who have a significant degree of rheumatic heart disease or a history of repeated occurrences should have prophylaxis indefinitely. The rec­ommended regimen for prophylaxis is 1.2 million units of benzathine penicillin monthly. Oral pen­icillin, erythromycin, or sulfadiazine can be used but because of noncompliance are somewhat less effective than the parenteral regimen.