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Guideline source: American Heart Association
Literature search described? No
Evidence rating system used? Yes
Published source: Circulation, March 24, 2009
Available at: http://circ.ahajournals.org/content/vol119/issue11
Coverage of guidelines from other sources does not imply endorsement by AFP or the AAFP.
Although the overall incidence of acute rheumatic fever and rheumatic heart disease is low in most areas of the United States, they are the leading causes of cardiovascular death during the first five decades of life in developing countries. This disparity serves as a reminder of the importance of continued vigilance to prevent these diseases. The American Heart Association (AHA) recently updated its recommendations on the prevention of rheumatic fever.
Primary Prevention of Rheumatic Fever
Group A streptococcus (GAS) infections of the pharynx are the precipitating cause of rheumatic fever. Proper diagnosis and adequate antibiotic treatment of GAS infections can prevent acute rheumatic fever in most cases.
DIAGNOSIS OF STREPTOCOCCAL PHARYNGITIS
Acute pharyngitis is caused much more often by viruses than by bacteria. However, differentiation of GAS pharyngitis from other causes of acute pharyngitis is often difficult because none of the clinical findings suggestive of GAS infection is specific enough on its own for diagnosis (Table 1). A history of recent exposure is helpful in making the diagnosis, as is an awareness of the prevalence of GAS infections in the community.
If clinical and epidemiologic findings suggest GAS infection, microbiologic confirmation with a throat culture or rapid antigen detection test (RADT) is required. The diagnosis of GAS pharyngitis is more easily excluded than confirmed, so testing usually is unnecessary in patients with findings suggestive of a viral origin. Treatment is indicated for patients with acute pharyngitis who have a positive throat culture or RADT. However, because of the low sensitivity of many RADTs, a negative test does not exclude GAS infection, and a throat culture usually should be performed. The exception is in adults, in whom the incidence of GAS pharyngitis and the risk of acute rheumatic fever are low. In this population, diagnosis of GAS pharyngitis can be made on the basis of an RADT alone, without confirmation of negative results by a throat culture.
Antistreptococcal antibody titers reflect past-not present- immunologic events and therefore cannot be used to determine whether a patient with pharyngitis...