Acute Rheumatic Fever and Rheumatic Heart Disease by luckboy


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									AD 9/02

Acute Rheumatic Fever and Rheumatic Heart Disease
Key Points: 1. Acute rheumatic fever occurs a few weeks after Group A Strep pharyngitis. 2. Carditis, arthritis, erythema migrans, subcutaneous nodules, and chorea are some of the major findings and should raise your suspicion for ARF. 3. Mitral stenosis is a complication of ARF and may require surgical intervention. 4. Length of chronic treatment after the acute episode is controversial, but should be continued for at least ten years after diagnosis of ARF. What is acute rheumatic fever? --a nonsuppurative consequence of a pharyngeal infection by group A streptococcus (Strep pyogenes). Occurs 2-3 weeks after throat symptoms and is diagnosed clinically with Jones criteria. How common is it? Not very common in US, as many pts with sore throats get treated with antibiotics. Worldwide an estimated 10-20 million people get acute RF yearly! Rheumatic heart disease is the most common cause of valvular heart disease in the world. Most common in children ages 4-9 years old, but adults can get ARF. How do you diagnose it? Generally a clinical diagnosis with laboratory confirmation. Jones criteria are often used. For a firm diagnosis need 2 major criteria or one major and 2 minor criteria PLUS evidence of recent streptococcal infection. Major Criteria: • Carditis: Is a pancarditis affecting all layers from the pericardium to the endocardium. May see: --sx of pericarditis --new and changing murmurs, especially mitral regurg. This acute presentation is different from the later sequelae of rheumatic heart disease (mitral stenosis). --congestive heart failure symptoms which look similar to viral myocarditis --any degree of heart block --cardiomegaly on CXR • Arthritis --migratory polyarthritis usually of large joints --often see more joint pain than objective signs of inflammation, especially if taking NSAIDs --each affected joint inflamed for less than one week and typically over 6 joints involved --were you to tap the fluid, you’d see a sterile inflammatory change. Serum complement often normal. • Chorea: Also called Sydenham chorea or St. Vitus dance. --abrupt, purposeless, nonrhythmic, involuntary movements, usually worse on one side --muscle weakness can be elicited by rhythmic squeezing of hand…the “milking sign” --emotional changes include crying, inappropriate behavior, restlessness --chorea can occur up to 8 months after strep infection • Subcutaneous nodules --firm, painless, noninflamed, variable in size --often symmetric when multiple and located over bony surfaces or near tendons --appear earlier in course of ARF and usually only in patients with carditis --different from rheumatoid nodules because smaller (millimeters up to 2 centimeters), short-lived, on olecranon rather than distal to it • Erythema marginatum --pink, evanescent, non-itchy rash on trunk and limbs, but not on face --often extends outward and center skin returns to normal, giving “erythema annulare” --lesions can come and go in hours; heat brings them out --usually happens early in disease or recurs after other sx are gone. --usually only in patients with carditis Minor criteria a) Fever b) Arthralgia c) Previous rheumatic fever or rheumatic heart disease Laboratory Diagnosis • Increased ASO titer or strep antibodies • Positive throat culture for Group A beta-hemolytic strep • Recent scarlet fever

AD 9/02 **Antibodies are better than culture because culture often negative. Antibody titer usually peaks at 4-5 weeks after pharygitis. Cannot use titers as indicator of disease activity after initial illness. What is the treatment of ARF? a) For symptoms: aspirin or other anti-inflammatory meds. Continue until all symptoms are absent. b) Antibiotics --Acute treatment: Oral penicillin 500mg BID-TID for 10 days, or 1.2 mU IM once. Use erythromycin 40mg/kg/day divided in 2-4 doses or a cephalosporing if PCN allergic. Treat even if no pharyngitis at the time of diagnosis. Culture family contacts and treat if positive. --Chronic treatment: PCN 250 mg BID or sulfadiazine 1000mg/day, or PCN IM 1.2 mU q month, or erthyromycin 250 mg BID. If chronic therapy is terminated, patients with mitral stenosis should get prophylaxis for specific dental, GU, and GI procedures. How long should you continue chronic treatment? The jury is out. Most recurrences of ARF occur in first two years but can happen later as well. Some argue for indefinite treatment and others say 10 years from an acute attack. The goal of secondary prophylaxis is to prevent future episodes of ARF which could worsen underlying deficits. Number of previous attacks, the time lapsed since the last attack, the risk of exposure to streptococcal infections, the age of the patient, and the presence or absence of cardiac involvement should be taken into consideration in determining length of secondary prophylaxis. Future strep vaccines may change this practice. What are the late sequelae of acute rheumatic fever? Rheumatic heart disease occurs 10-20 years after original attack. Probably develops in over 50% of patients with initial carditis. What is the mechanism of RHD? Tiny nodules gather on the valve leaflets in acute rheumatic fever. Over time fibrin deposition occurs and valves thicken or fuse. Another proposed mechanism is acute inflammation causing adhesion of commisures and then degenerative sequelae. A subclinical inflammatory process caused by the stress of chronic turbulent flow due to the deformed valve contributes to the progression of stenosis. With time there is a gradual loss of valve area. What are the valve findings and when do they occur? Mitral stenosis is most common finding, followed by aortic stenosis. Some studies suggest that over 70% of MS is caused by RHD. Stenosis occurs 10-20 years after infection but symptoms may be delayed as late as 40 years. In developing countries, onset of symptoms often occurs earlier due to lack of antibiotics or more virulent strains causing earlier adhesion of leaflets. When does the patient need an intervention? Symptoms drive the need for intervention. Can do closed or open commisurotomy, percutaneous balloon valvotomy, or valve replacement. Controversy exists as to the appropriateness of an intervention in asymptomatic patients with severe MS (valve area <1.5cm2); some argue for it if pt has moderate or severe pulmonary HTN or atrial fibrillation and pliable valves (valvotomy or commisurotomy). MV replacement should occur in symptomatic pts (NYHA Class III-IV) with severe MS where valvotomy not feasible (ie persistent atrial thrombus, nonpliable or calcified valve). What are the complications? • Congestive heart failure: Mortality is related to patient’s functional status. Before the era of CHF med advances, NYHA IV pts 10-year survival was 0% compared to 80% for NYHA I. • Atrial fibrillation: occurs in over 45% of MS patients • Pulmonary HTN: mean survival without surgery 2.4 years • Thromboembolic events: mostly occur in pts with atrial fibrillation, but can happen in NSR in pts with MS • Bacterial endocarditis

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