Cardiology > Rheumatic fever   

Background     

Rheumatic fever (RF) is an autoimmune, inflammatory complication that occurs after a group A Streptococcus (GAS) pharyngitis infection. It primarily affects the heart, joints, skin, and central nervous system. If untreated, it can lead to rheumatic heart disease (RHD), characterized by permanent valvular damage—most commonly involving the mitral valve. 

II) Classification/Types

By Organ Involvement: 

• • Carditis: Pancarditis involving endocardium (valvulitis), myocardium, and pericardium 

• • Polyarthritis: Migratory arthritis, primarily affecting large joints 

• • Chorea (Sydenham chorea): Involuntary movements due to CNS involvement 

• • Subcutaneous nodules: Firm, painless lumps over extensor surfaces 

• • Erythema marginatum: Pink, serpiginous rash with central clearing 

By Clinical Pattern: 

• • Acute Rheumatic Fever (ARF): First symptomatic episode post-streptococcal pharyngitis 

• • Recurrent RF: New episode in previously affected individuals, usually with incomplete prophylaxis 

• • Rheumatic Heart Disease (RHD): Chronic valvular sequelae from repeated or severe episodes 

Pathophysiology 

Rheumatic fever is triggered by molecular mimicry, where the immune system generates antibodies against the M protein of GAS that cross-react with human tissues, particularly in the heart and joints. T cells and antibodies infiltrate and damage the myocardium and valvular endothelium, leading to inflammation, fibrosis, and potential permanent scarring, particularly of the mitral valve. 

Epidemiology 

• • Most common in children aged 5–15 years 

• • Incidence highest in low- and middle-income countries 

• • Major contributor to cardiovascular disease in young adults in endemic regions 

• • Peak incidence during winter and spring (when strep infections are common) 

Etiology 

I) Causes 

• • Untreated or inadequately treated group A Streptococcus (GAS) pharyngitis 

• • Recurrent streptococcal infections in predisposed individuals 

II) Risk Factors 

• • Age 5–15 years 

• • Crowded living conditions (e.g., schools, refugee camps) 

• • Family history of RF or RHD 

• • Limited access to healthcare 

• • Inadequate antibiotic treatment of strep throat 

Clinical Presentation 

I) History (Symptoms) 

• • Occurs 2–4 weeks after GAS pharyngitis 

• • Fever, malaise 

• • Migratory joint pain 

• • Chest pain, palpitations (carditis) 

• • Involuntary movements (chorea) 

• • Emotional lability or irritability 

• • Skin lesions (erythema marginatum, nodules) 

II) Physical Exam (Signs) 

• • Polyarthritis: Swelling, redness, and pain, especially in knees, ankles 

• • Carditis: New murmur (typically mitral regurgitation), tachycardia, pericardial rub 

• • Sydenham chorea: Rapid, uncoordinated jerking movements 

• • Subcutaneous nodules over bony prominences 

• • Erythema marginatum: Annular, pink rash on trunk/extremities 

Differential Diagnosis (DDx) 

• • Infective endocarditis 

• • Systemic lupus erythematosus (SLE) 

• • Juvenile idiopathic arthritis 

• • Viral myocarditis 

• • Post-streptococcal reactive arthritis 

• • Kawasaki disease 

Diagnostic Tests 

Initial Work-Up 

• • Throat culture or rapid antigen test for GAS 

• • Elevated ESR/CRP: Inflammatory markers 

• • ASO titer (antistreptolysin O): Evidence of recent strep infection 

• • Echocardiography: Valvular involvement (mitral regurgitation) 

• • ECG: Prolonged PR interval, sinus tachycardia 

• • Jones Criteria: Used for diagnosis 

Modified Jones Criteria for Initial Episode (2023 AHA Update): 

Major Criteria 

• • Carditis (clinical or subclinical) 

• • Polyarthritis or monoarthritis (low-risk populations) 

• • Sydenham chorea 

• • Erythema marginatum 

• • Subcutaneous nodules 

Minor Criteria 

• • Fever 

• • Arthralgia 

• • Elevated ESR/CRP 

• • Prolonged PR interval 

Plus evidence of preceding GAS infection 

Treatment 

I) Initial Approach 

• • Eradicate GAS: Penicillin G benzathine IM or oral penicillin VK 

• • Anti-inflammatory therapy: Aspirin or NSAIDs for arthritis/carditis 

• • Steroids: For severe carditis or heart failure 

• • Supportive care: Bed rest during acute phase 

II) Medications 

Patient Education, Screening, Vaccines 

Education 

• • Importance of early treatment of sore throat 

• • Adherence to secondary prophylaxis 

• • Monitoring for symptoms of heart failure or chorea 

Screening 

• • Throat cultures for symptomatic patients in endemic areas 

• • Echocardiographic screening in high-risk populations 

Vaccinations 

• • Influenza and pneumococcal vaccines to reduce risk of secondary infections in RHD 

• • HPV and COVID-19 vaccines as per national guidelines 

Consults/Referrals 

• • Cardiology: Valvular involvement, RHD monitoring 

• • Neurology: For Sydenham chorea 

• • Rheumatology: For differential diagnosis or chronic arthritis 

• • Pediatrics/ID: Long-term management and prophylaxis 

Follow-Up 

Short-Term 

• • Monitor for resolution of arthritis and fever 

• • Echocardiography for cardiac assessment 

• • Repeat ASO titers not routinely needed 

Long-Term 

• • Secondary prophylaxis: IM benzathine penicillin every 3–4 weeks 

• • Duration depends on severity and presence of carditis: 

• • No carditis: 5 years or until age 21 

• • Carditis without valvular disease: 10 years or until age 21 

• • Carditis with persistent valvular disease: 10 years or until age 40 (or lifelong) 

• • Serial echocardiograms to monitor valvular function 

• • Education on dental hygiene to prevent endocarditis 

Prognosis 

• • Excellent if diagnosed early and treated promptly 

• • Recurrences common without secondary prophylaxis 

• • Chronic rheumatic heart disease may result in: 

• • Heart failure 

• • Atrial fibrillation 

• • Stroke 

• • Need for valve replacement