Rheumatic Fever Overview

Rheumatic Fever Overview

• Acute rheumatic fever (ARF) is a complication of group A streptococcal pharyngeal infections.
• Symptoms develop two to three weeks after the infection and can include arthritis, carditis, chorea, subcutaneous nodules, and erythema marginatum.
• Risk factors include age (most common in school-age children 5-15 years old), genetics, and environmental factors like overcrowding and poor sanitation.
• Rheumatic fever is caused by group A beta-hemolytic streptococci, often from untreated strep throat.
• Group A strep infections of the skin or other body parts can rarely cause rheumatic fever.
• Molecular mimicry is the pathogenic mechanism; autoantibodies and T cells target group A strep cell wall (M protein) and mimic bacterial material in healthy tissues.

Presentation

• History of streptococcal pharyngitis or skin infections two to four weeks before ARF onset is typical.
• Symptoms include: arthritis (wrist, knee, elbow, ankle pain), chorea (jerky movements), fatigue, fever, subcutaneous nodules, and rash (erythema marginatum).
• Complications include rheumatic heart disease (possible weakening of valves and associated complications like chest pain, tachycardia, dyspnea, murmurs).

Diagnosis

• Diagnosis is based on the Modified Jones Criteria.
• Requires presence of two major criteria or one major and two minor criteria for initial ARF diagnosis.
• Recurrent episodes require different criteria, potentially including three minor criteria.

Major Criteria

• Rheumatic arthritis
• Rheumatic carditis (inflammation of the heart)
• Rheumatic chorea (jerky movements)
• Subcutaneous nodules
• Erythema marginatum (rash)

Minor Criteria

• Polyarthritis (joint pain)
• Fever ≥ 38.5°C
• Elevated erythrocyte sedimentation rate (ESR) > 60 mm/h and/or C-reactive protein (CRP) > 3.0 mg/dL
• Prolonged PR interval on electrocardiogram (ECG)
• Positive laboratory tests for recent streptococcal infection (ASO, anti-DNase B titers)

Treatment Acute Rheumatic Fever

• Treatment goals: relieve symptoms, eradicate streptococcal infection, prevent future recurrences, and mitigate cardiac damage.
• Hospitalization is often necessary to confirm diagnosis and facilitate echocardiogram.
• Symptoms like arthritis: First-line treatment usually includes non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen or naproxen.
• Carditis: Treatment includes anti-inflammatory drugs like prednisolone along with other measures like IVIG, beta-blockers, or amiodarone depending on the severity.
• Heart failure: Add ACE inhibitors (e.g., captopril) and diuretics.
• Sydenham chorea: May resolve spontaneously or require medications like corticosteroids or antipsychotics.

Eradication of Streptococci

• Treatment for streptococcal infection typically involves antibiotics like amoxicillin, penicillin V, or procaine penicillin G, depending on patient weight and health.

Prevention of Rheumatic Fever

• Reducing the spread of group A strep is crucial.
• Early diagnosis and appropriate treatment of streptococcal infections are critical in preventing the initial attack of ARF.
• Preventing recurrent attacks focuses on preventing further streptococcal infections.
• Duration of antibiotic prophylaxis varies greatly depending on whether there was carditis, valvular involvement, etc.

Prevention against Bacterial Endocarditis

• Patients at risk (e.g., rheumatic heart disease) require prophylactic antibiotics before dental procedures or invasive respiratory surgeries.
• Antibiotics like amoxicillin, cephalexin, ampicillin, or ceftriaxone, or doxycycline or azithromycin are used based on allergic status.