There are five major clinical manifestations of acute renal failure (ARF): carditis, polyarthritis, chorea, subcutaneous nodules, and erythema marginatum. Carditis develops in about 60% of patients; it involves the endocardium, myocardium, and pericardium. The typical manifestations of rheumatic carditis are sinus tachycardia (sometimes with first-degree heart block), mitral regurgitation, a pericardial friction rub, and cardiomegaly; congestive heart failure indicates severe carditis. Although most cases of carditis resolve within 3 months, patients with moderate to severe carditis or recurrent ARF are at risk for the late manifestation of mitral valve or aortic valve scarring. Polyarthritis develops in about 70% of patients with ARF. It is characteristically a migratory arthritis involving the large joints of the extremities; it resolves without sequelae in days to weeks. On rare occasions, adults may develop a persistent arthropathy of the hands and feet. Chorea, subcutaneous nodules, and erythema marginatum are all self-limited; each occurs in fewer than 10% of children with ARF and only very rarely in adults.
The minor manifestations of ARF are fever, arthralgias, and inflammation. The inflammation in such cases is evidenced by elevated erythrocyte sedimentation rates and C-reactive protein levels. The diagnosis of ARF is made on the basis of clinical features. The classic Jones criteria include the presence of either two major manifestations or one major and two minor manifestations, as well as laboratory evidence of a recent streptococcal infection (e.g., a positive throat culture or rising antistreptococcal antibody levels).
Treatment of ARF focuses on eradication of streptococcal pharyngitis and reduction of inflammation. Most clinicians recommend a course of penicillin or, as an alternative, other antistreptococcal antibiotics, even if the throat culture is negative at the time ARF is diagnosed. Antiinflammatory therapy includes aspirin and bed rest until inflammatory symptoms resolve; corticosteroids may have a role for patients with severe carditis.
ARF can be prevented by adequate treatment of streptococcal pharyngitis, even if antibiotics are delayed for up to 9 days after the onset of pharyngitis. Patients with a history of ARF are particularly vulnerable to recurrent attacks. Consequently, they should receive continuous prophylaxis for at least 5 years with daily oral penicillin (250 mg twice a day) or monthly injections of 1.2 million units of benzathine penicillin G. Prophylaxis can be discontinued when young patients who are at low risk for recurrence reach adulthood or when small children are no longer in the household.