What are the clinical presentation and treatment options for a patient with a history of streptococcal (Streptococcus) infection, such as pharyngitis, suspected of having acute rheumatic fever?

Clinical Presentation of Acute Rheumatic Fever

Acute rheumatic fever presents 14-21 days after group A streptococcal pharyngitis with a combination of major manifestations (carditis, polyarthritis, chorea, erythema marginatum, subcutaneous nodules) and minor manifestations (fever, arthralgia, elevated inflammatory markers), diagnosed using the Jones criteria requiring two major OR one major plus two minor criteria, along with evidence of preceding streptococcal infection. 1, 2

Major Clinical Manifestations

Carditis is the most serious manifestation and presents with: 1, 3

• New heart murmur indicating valvular involvement (mitral and/or aortic regurgitation most common)
• Pericardial friction rub suggesting pancarditis
• Signs of heart failure in severe cases
• Tachycardia out of proportion to fever
• Echocardiography with Doppler should be performed immediately to characterize valvulitis and document baseline cardiac status, as clinical detection of soft murmurs may be difficult due to tachycardia 1, 3

Polyarthritis typically manifests as: 4, 5

• Migratory arthritis affecting large joints (knees, ankles, elbows, wrists)
• Exquisitely painful and swollen joints
• Each joint affected for 1-2 days before migrating to another
• Dramatic response to salicylates within 24-48 hours

Sydenham's chorea (occurs in 10-30% of cases): 5, 6

• Involuntary, purposeless movements of extremities and face
• Emotional lability and behavioral changes
• May appear months after the initial infection (latency up to 6 months)
• Often occurs without other manifestations

Erythema marginatum: 1, 4

• Pink or faintly red, non-pruritic rash with clear centers
• Serpiginous borders that extend outward
• Primarily on trunk and proximal extremities, sparing the face
• Evanescent, may come and go

Subcutaneous nodules (rare, <5% of cases): 1, 5

• Firm, painless nodules over bony prominences
• Extensor surfaces of joints (elbows, knees, wrists)
• Usually associated with severe carditis

Minor Clinical Manifestations

• Fever: typically 38.5-40°C (101-104°F) 7
• Arthralgia: joint pain without objective swelling (cannot use if arthritis is a major criterion) 5
• Malaise and constitutional symptoms indicating systemic inflammatory response 1

Laboratory and Diagnostic Findings

Evidence of preceding streptococcal infection (mandatory for diagnosis): 1, 3

• Elevated or rising anti-streptolysin O (ASO) titers (elevated in ~80% of ARF cases, peak at 3-6 weeks post-pharyngitis)
• Elevated anti-DNase B antibodies (more sensitive for skin infections)
• Positive throat culture for group A streptococcus (often negative by time of ARF presentation)

Acute phase reactants: 1, 3

• Elevated erythrocyte sedimentation rate (ESR)
• Elevated C-reactive protein (CRP)

Electrocardiogram findings: 3, 5

• Prolonged PR interval (first-degree AV block)
• Other conduction abnormalities in severe carditis

Critical Diagnostic Pitfalls

At least one-third of ARF cases result from inapparent streptococcal infections, meaning patients never had recognized pharyngitis, making the diagnosis challenging 1, 2. The GAS infection need not be symptomatic to trigger rheumatic fever 1.

Approximately 15% of school-age children are asymptomatic GAS carriers, making it difficult to distinguish between true infection and carriage with concurrent viral pharyngitis 1. However, Group C and G streptococcal pharyngitis do NOT cause acute rheumatic fever despite presenting identically to GAS pharyngitis 1.

Significant overlap exists with other conditions including Lyme disease, serum sickness, drug reactions, and post-streptococcal reactive arthritis, requiring careful differentiation 1, 5.

Jones Criteria Application

For initial ARF diagnosis, require: 1, 3, 5

• Two major criteria OR one major plus two minor criteria
• PLUS supporting evidence of antecedent group A streptococcal infection

Exceptions to standard Jones criteria exist for: 3

• Patients with isolated chorea (may not meet full criteria)
• Indolent carditis (subtle, slowly progressive)
• Previous history of rheumatic fever or rheumatic heart disease (lower threshold for diagnosis)

Immediate Management Approach

Eradicate residual streptococcal infection: 1, 2

• Administer full therapeutic course of penicillin immediately, even if throat culture is negative
• Penicillin V 250 mg twice daily for children, 500 mg 2-3 times daily for adolescents/adults for 10 days 2
• Treatment must continue for at least 10 days to prevent acute rheumatic fever 8

Anti-inflammatory therapy: 1, 2

• Salicylates for arthritis and mild carditis (usually initial treatment of choice) 9
• Corticosteroids reserved for severe carditis with heart failure 1

Initiate secondary prophylaxis immediately: 1, 2

• Benzathine penicillin G for lifelong prevention of recurrent ARF
• Continuous antimicrobial prophylaxis is required rather than episodic treatment because recurrent ARF can occur even with appropriate treatment of symptomatic GAS infections 1

Duration of prophylaxis depends on cardiac involvement: 1

• No carditis: 5 years or until age 21 (whichever is longer)
• Carditis without residual disease: 10 years or until age 21 (whichever is longer)
• Carditis with residual valvular disease: 10 years or until age 40, sometimes lifelong

Screen household contacts: 1

• Obtain throat swab specimens from ALL household contacts
• Treat positive contacts regardless of symptoms to prevent transmission and potential ARF in susceptible individuals

Long-term Implications

Patients with previous ARF are at very high risk for recurrent attacks when GAS pharyngitis develops, with each recurrence potentially worsening rheumatic heart disease 1, 2. Recurrent GAS infections lead to repeated ARF episodes, causing progressive valvular damage through chronic inflammation resulting in commissural fusion, leaflet thickening, chordal shortening, and eventual calcification 1.

Rheumatic fever carries significant risk of permanent cardiac damage, with potential for severe rheumatic heart disease requiring lifelong management and possible surgical intervention 2.