What are the symptoms of rheumatic fever?

Symptoms of Rheumatic Fever

Rheumatic fever presents with a constellation of symptoms including carditis, polyarthritis, chorea, erythema marginatum, and subcutaneous nodules as major manifestations, along with fever, elevated inflammatory markers, and prolonged PR interval as minor manifestations. 1, 2

Major Manifestations

Carditis (50-70% of cases)

• Clinical findings: New murmurs, tachycardia out of proportion to fever, precordial pain
• Subclinical carditis: Detected only by echocardiography (Doppler showing pathological regurgitation)
• Can involve endocardium, myocardium, and pericardium

Arthritis (35-66% of cases)

• Typically migratory polyarthritis affecting large joints
• In high-risk populations, monoarthritis or polyarthralgia may be sufficient for diagnosis
• Characteristically responds dramatically to anti-inflammatory medications

Sydenham's Chorea (10-30% of cases)

• Involuntary, purposeless movements
• More common in females
• May appear late in the disease course
• Often accompanied by emotional lability and muscle weakness

Erythema Marginatum (<6% of cases)

• Non-pruritic, painless, pink rash with clear centers and rounded edges
• Typically appears on trunk and proximal extremities
• Transient and can be elicited by applying heat

Subcutaneous Nodules (0-10% of cases)

• Firm, painless nodules over bony prominences or tendons
• Usually appear during the inflammatory phase

Minor Manifestations

Fever

• In low-risk populations: Usually exceeds 38.5°C orally
• In high-risk populations: May be lower (>37.5°C may be significant) 1

Laboratory Findings

• Elevated erythrocyte sedimentation rate (ESR): >60 mm in first hour in low-risk populations; >30 mm/h may be considered in high-risk populations
• Elevated C-reactive protein (CRP): >3.0 mg/dL (commonly >7.0 mg/dL)
• Leukocytosis: >10,000 white blood cells/mm³ 1, 2

Electrocardiographic Changes

• Prolonged PR interval
• May have other conduction abnormalities

Other Symptoms

• Abdominal pain
• Malaise
• Anemia
• Epistaxis (nosebleeds)
• Rapid sleeping pulse rate 1

Diagnostic Considerations

The diagnosis of rheumatic fever requires evidence of preceding group A streptococcal infection plus either:

• Two major criteria, or
• One major and two minor criteria 1, 2

Evidence of Preceding Streptococcal Infection

• Positive throat culture for group A streptococcus
• Elevated antistreptolysin-O or other streptococcal antibodies
• Recent scarlet fever 1

Important Clinical Pearls

1. Normal inflammatory markers virtually exclude ARF - except in isolated chorea, ESR and CRP are almost never normal in acute rheumatic fever 1

2. Different diagnostic thresholds for different populations:

   • Low-risk: ARF incidence <2 per 100,000 school-aged children or RHD prevalence ≤1 per 1000
   • Moderate/high-risk: All other populations 1

3. Echocardiography is essential - All patients with suspected rheumatic fever should undergo echocardiography, even without clinical signs of carditis 3

4. Symptoms typically develop 2-3 weeks after streptococcal pharyngitis - This latent period is characteristic of the autoimmune response 4

5. Differential diagnosis must be considered - Symptoms may overlap with Lyme disease, serum sickness, drug reactions, and post-streptococcal reactive arthritis 5

The recognition of rheumatic fever symptoms is critical as early diagnosis and treatment can prevent progression to rheumatic heart disease, which remains a leading cause of cardiovascular mortality in developing nations 6.