Rheumatic Fever

Overview

Rheumatic fever is a serious inflammatory disease that can develop as a complication of untreated or inadequately treated strep throat or scarlet fever. This condition occurs when the body's immune system attacks its own tissues after fighting off a streptococcal infection, a process known as molecular mimicry. Rheumatic fever can affect multiple organs, including the heart, joints, brain, and skin.

The condition is most commonly seen in children between the ages of 5 and 15, though it can occur in adults. Rheumatic fever is particularly concerning because it can cause permanent damage to the heart valves, leading to rheumatic heart disease, which can be a lifelong condition requiring ongoing medical management.

While rheumatic fever has become rare in developed countries due to improved living conditions and access to antibiotics, it remains a significant health problem in developing nations. Early recognition and proper treatment of strep throat is crucial for preventing rheumatic fever, as the condition is entirely preventable with appropriate antibiotic therapy.

Symptoms

Rheumatic fever symptoms typically appear 1-5 weeks after a strep throat infection and can vary significantly between individuals. The condition is diagnosed using the Jones criteria, which include major and minor manifestations.

Major Manifestations (Jones Criteria)

Additional Major Symptoms

• Sydenham's chorea: Involuntary muscle movements, emotional instability
• Erythema marginatum: Pink ring-shaped rash on trunk and limbs
• Subcutaneous nodules: Small, painless lumps under the skin

Minor Manifestations

• Fever: Usually above 101°F (38.3°C)
• Joint pain (arthralgia): Without obvious swelling
• Elevated inflammatory markers: ESR, CRP in blood tests
• Prolonged PR interval: On electrocardiogram (ECG)
• Previous rheumatic fever: History of the condition

Cardiac Symptoms

Heart involvement (carditis) can cause:

• Chest pain or discomfort
• Shortness of breath
• Rapid or irregular heartbeat
• Fatigue and weakness
• Swelling in legs, ankles, or abdomen
• New heart murmur

Neurological Symptoms (Sydenham's Chorea)

• Jerky, uncontrollable movements
• Muscle weakness
• Emotional lability (mood swings)
• Difficulty with fine motor skills
• Speech difficulties

Causes

Rheumatic fever is caused by an abnormal immune response to a Group A Streptococcus (GAS) bacterial infection, typically strep throat or scarlet fever.

The Development Process

The condition develops through the following mechanism:

• Initial infection: Group A Streptococcus bacteria infect the throat
• Immune response: Body produces antibodies to fight the strep bacteria
• Molecular mimicry: Strep proteins resemble human tissue proteins
• Cross-reaction: Antibodies mistakenly attack the body's own tissues
• Inflammation: Immune attack causes inflammation in heart, joints, brain, and skin

Streptococcal Infections That Can Lead to Rheumatic Fever

• Strep throat: Most common cause
• Scarlet fever: Strep infection with characteristic rash
• Impetigo: Superficial skin infection (less common cause)
• Cellulitis: Deep skin and soft tissue infection

Why Only Some People Develop Rheumatic Fever

Several factors determine who develops rheumatic fever after strep infection:

• Genetic susceptibility: Certain HLA types increase risk
• Bacterial strain: Some strep strains are more rheumatogenic
• Immune system factors: Individual immune response variations
• Environmental factors: Overcrowding, poor nutrition, inadequate healthcare
• Age: Children and adolescents are more susceptible

Time Course

• Latent period: 1-5 weeks after strep infection
• Peak incidence: 2-3 weeks post-infection
• Duration: Acute phase lasts 6-12 weeks if untreated

Risk Factors

Several factors increase the likelihood of developing rheumatic fever after a streptococcal infection:

Age-Related Risk Factors

• Peak age: 5-15 years old
• Rare before age 3: Very uncommon in toddlers
• Decreasing risk with age: Less common in adults
• First episode risk: Higher in children and adolescents

Genetic and Family Factors

• Family history: Genetic predisposition to rheumatic fever
• HLA types: Certain genetic markers increase susceptibility
• Ethnic factors: Some populations have higher risk
• Previous rheumatic fever: Significantly increases risk of recurrence

Environmental and Social Factors

• Overcrowding: Close living conditions increase transmission
• Poor hygiene: Inadequate sanitation and hygiene practices
• Poverty: Limited access to healthcare and antibiotics
• Malnutrition: Weakened immune system
• Climate: More common in temperate climates

Healthcare Access Factors

• Delayed treatment: Late or inadequate antibiotic treatment for strep
• Incomplete treatment: Not finishing prescribed antibiotics
• Undiagnosed strep: Mild or asymptomatic strep infections
• Limited medical access: Remote or underserved areas

Geographic Risk Factors

• Developing countries: Higher incidence due to healthcare limitations
• Indigenous populations: Higher rates in some indigenous communities
• Institutional settings: Schools, military barracks, camps
• Seasonal patterns: More common in fall and winter months

Diagnosis

Diagnosing rheumatic fever can be challenging as there is no single definitive test. Healthcare providers use the Jones criteria, established by the American Heart Association, to make the diagnosis.

Jones Criteria for Diagnosis

Diagnosis requires evidence of preceding strep infection plus:

• 2 major manifestations, OR
• 1 major + 2 minor manifestations

Major Manifestations:

• Carditis (heart inflammation)
• Polyarthritis (multiple joint inflammation)
• Sydenham's chorea (involuntary movements)
• Erythema marginatum (characteristic rash)
• Subcutaneous nodules

Minor Manifestations:

• Fever (≥38.5°C or 101.3°F)
• Arthralgia (joint pain without swelling)
• Elevated acute phase reactants (ESR ≥60 mm/hr, CRP ≥3.0 mg/dL)
• Prolonged PR interval on ECG

Laboratory Tests

Evidence of Streptococcal Infection:

• ASO titer: Antistreptolysin O antibodies (elevated)
• Anti-DNase B: Anti-deoxyribonuclease B antibodies
• Streptozyme test: Multiple strep antibodies
• Throat culture: May be negative if taken weeks after infection

Inflammatory Markers:

• ESR: Erythrocyte sedimentation rate (elevated)
• CRP: C-reactive protein (elevated)
• White blood cell count: Often elevated

Cardiac Evaluation

• Electrocardiogram (ECG): Check for PR interval prolongation, arrhythmias
• Echocardiogram: Assess heart valve function and inflammation
• Chest X-ray: Evaluate heart size and lung involvement

Additional Tests

• Joint aspiration: If joint infection suspected
• Brain MRI: If neurological symptoms present
• Blood cultures: Rule out other infections

Differential Diagnosis

Conditions that may mimic rheumatic fever:

• Juvenile idiopathic arthritis
• Viral arthritis
• Infective endocarditis
• Systemic lupus erythematosus
• Post-infectious glomerulonephritis

Treatment Options

Treatment of rheumatic fever focuses on eliminating any remaining streptococcal bacteria, reducing inflammation, managing symptoms, and preventing complications and recurrence.

Antibiotic Treatment

Acute Phase Treatment:

• Penicillin: First-line treatment to eliminate strep bacteria
• Benzathine penicillin G: Single intramuscular injection
• Oral penicillin V: 10-day course for those who can take oral medication
• Alternative antibiotics: Erythromycin, clindamycin for penicillin-allergic patients

Long-term Prophylaxis:

• Benzathine penicillin G: Every 4 weeks (intramuscular)
• Oral penicillin V: Daily (250 mg twice daily)
• Duration: Varies based on cardiac involvement and risk factors

Anti-inflammatory Treatment

For Arthritis:

• Aspirin: High-dose (80-100 mg/kg/day) for joint inflammation
• NSAIDs: Alternative to aspirin (naproxen, ibuprofen)
• Duration: Continue until symptoms resolve and labs normalize

For Carditis:

• Corticosteroids: Prednisolone for severe carditis
• Aspirin: May be used for mild carditis
• Heart failure management: ACE inhibitors, diuretics if needed

Specific Symptom Management

Sydenham's Chorea:

• Valproic acid: First-line treatment for chorea
• Carbamazepine: Alternative anticonvulsant
• Haloperidol: For severe cases (used cautiously)
• Rest and sedation: Quiet environment, minimal stimulation

Heart Failure:

• Bed rest: During acute carditis phase
• Diuretics: For fluid overload
• ACE inhibitors: To reduce heart workload
• Digoxin: For heart rhythm management if needed

Supportive Care

• Rest: Bed rest during acute phase
• Nutrition: Adequate nutrition to support healing
• Pain management: Appropriate analgesics
• Monitoring: Regular cardiac and joint assessments

Long-term Management

• Regular follow-up: Cardiac monitoring and prophylaxis compliance
• Dental prophylaxis: Antibiotics before dental procedures
• Lifestyle modifications: Heart-healthy diet and appropriate exercise
• Education: Recognition of strep symptoms and early treatment

Prevention

Prevention of rheumatic fever is entirely achievable through proper recognition and treatment of streptococcal infections, particularly strep throat.

Primary Prevention

Preventing the first episode of rheumatic fever:

• Early recognition of strep throat: Seek medical attention for sore throat with fever
• Rapid strep testing: Quick diagnosis in healthcare settings
• Appropriate antibiotic treatment: Complete course of prescribed antibiotics
• Prompt treatment: Start antibiotics within 9 days of symptom onset

Secondary Prevention

Preventing recurrent episodes in those who have had rheumatic fever:

• Long-term antibiotic prophylaxis: Continuous protection against strep
• Regular medical follow-up: Monitor for complications and compliance
• Duration of prophylaxis varies:
  • Without carditis: 5 years or until age 21 (whichever is longer)
  • With carditis but no residual heart disease: 10 years or until age 21
  • With residual heart disease: 10 years or until age 40
  • High-risk patients: May require lifelong prophylaxis

Infection Control Measures

• Good hygiene: Regular handwashing and respiratory etiquette
• Avoid close contact: Stay away from people with strep throat
• Don't share items: Avoid sharing eating utensils, drinks, or personal items
• Clean environment: Regular cleaning of frequently touched surfaces

Community Prevention Strategies

• Improved living conditions: Reduce overcrowding
• Better nutrition: Strengthen immune systems
• Healthcare access: Ensure availability of medical care and antibiotics
• Education programs: Public awareness about strep throat treatment

Special Considerations

• High-risk populations: Indigenous communities, developing countries
• Institutional settings: Schools, military bases, correctional facilities
• Healthcare workers: Recognition and proper treatment protocols
• Family screening: Check family members for strep when one person is infected

When to See a Doctor

Seek medical attention promptly if you or your child experience symptoms that may indicate rheumatic fever or complications:

Immediate Medical Attention

• Severe chest pain or difficulty breathing
• Signs of heart failure (swelling, extreme fatigue, rapid heartbeat)
• Sudden onset of involuntary movements (chorea)
• High fever with severe joint pain
• Symptoms of stroke or altered consciousness

Schedule Urgent Appointment

• Sore throat with fever and swollen lymph nodes
• Joint pain and swelling that moves from joint to joint
• Fever following recent strep throat infection
• New heart murmur or irregular heartbeat
• Skin rash with ring-like appearance
• Small bumps under the skin

Follow-up Care

For those with a history of rheumatic fever:

• Regular cardiac check-ups as recommended
• Any signs of strep throat infection
• Before dental or surgical procedures
• If experiencing medication side effects
• Pregnancy planning (women with rheumatic heart disease)

Preventive Care

• Any sore throat lasting more than 2-3 days
• Strep throat symptoms in family members
• Difficulty swallowing or severe throat pain
• Fever with headache and stomach pain

Related Conditions

Rheumatic fever is associated with several related conditions and complications:

Cardiac Complications

• Mitral valve disease: Most commonly affected valve
• Aortic valve disease: Second most commonly affected
• Heart failure: From severe valve damage
• Atrial fibrillation: Irregular heart rhythm
• Infective endocarditis: Increased risk with damaged valves

Other Streptococcal Complications

• PANDAS: Pediatric autoimmune neuropsychiatric disorders
• Reactive arthritis: Joint inflammation following infection
• Erythema nodosum: Inflammatory skin condition

Frequently Asked Questions

References

1. American Heart Association. Jones Criteria for Diagnosis of Rheumatic Fever. Circulation. 2023.
2. World Health Organization. Rheumatic Fever and Rheumatic Heart Disease. WHO Technical Report. 2023.
3. Centers for Disease Control and Prevention. Group A Streptococcal Disease. CDC Guidelines. 2023.
4. Rheumatic Heart Disease Global Status Report. RHD Action and World Heart Federation. 2023.
5. Pediatric Infectious Diseases Society. Management of Group A Streptococcal Pharyngitis. 2023.