Sore throats, streptococcal infections, and prevention of rheumatic fever

Abstract

Recent advances in laboratory and clinical investigation have shown the constant association of acute rheumatic fever with Group A beta-hemolytic streptococcal infections. Attempts to prevent rheumatic fever are accordingly aimed at eradication of Streptococci. This is an elusive target because there are no routine, simple clinical or laboratory indications of streptococcal infection. Patients with streptococcal infections may have sore throats but often are asymptomatic or have non-specific upper respiratory symptoms. Tests for Streptococci in the throat can be done easily but show only that the organism is present; they do not prove it is the causing infection. Antibody measurements can detect infection, but these tests are complex, cumbersome, and often require long delays to await acquisition of the sequential specimens required for demonstrating a change in titer. In preventing first attacks of rheumatic fever, physicians must find and then eradicate asymptomatic or atypical streptococcal infections as well as those that produce sore throats. Oral or parenteral penicillin, in adequate dosage, is the agent of choice for this purpose. Sulfonamides should not be employed therapeutically; erythromycin provides a feasible alternative when the use of penicillin is precluded. The major features used in deciding whether infection is present are a sore throat, and exudate, together with laboratory evidence of streptococcal infection. In preventing recurrent attacks of rheumatic fever in susceptible patients, physicians cannot rely on attempts to find and then treat streptococcal infections because the risk of missing asymptomatic infections is too great. Therefore, prevention of rheumatic recurrences requires continuous antimicrobial prophylaxis. At present, the most effective agent is a monthly injection of long-acting parenteral benzathine penicillin. The most effective oral agent to date has been sulfadiazine, 1.0 gram daily. Although it is currently recommended that all rheumatic patients maintain prophyl-axis indefinitely, rational considerations suggest that more finite durations can be planned for some patients on the basis of age, cardiac status, and length of time elapsed since the previous rheumatic attack.