• Information
  1. Etiology
  2. Rheumatic Fever
  3. Carditis
  4. Histopathology
  5. Diagnosis
  6. Treatment

A. Etiology

1. Sequellae of acute rheumatic fever due to Group A Streptococcal (GAS) infection
2. GAS
   1. The organism causes pharyngitis, usually tonsillitis
   2. Symptoms of acute rheumatic fever occur 3-26 weeks after infection
   3. Rheumatogenic strains are likely distinct from those which cause glomerulonephritis
   4. Epidemiology in developing nations is different from those in developed nations
   5. Patients are invariably >3 years old (schoolage)
3. Immunologic Mechanisms [5]
   1. Major immunologic acitivity against streptococcal M protein with antibody formation
   2. Antibodies to M protein cross react with cardiac (? other) tissue
   3. Two distinct antigenic classes of GAS
   4. Streptococcal superantigens can also cause generalized lymphocyte activation
   5. Macrophages and T lymphocytes (mainly CD8+ cells) required for RHD carditis
4. Incidence in USA is <2 per 100,000 persons

B. Rheumatic Fever (Major Jones' Criteria)

1. Carditis - pancarditis (peri-, myo-, endocarditis / vasculitis)
2. Arthritis, migratory, polyarticular with fevers, Jaccoud's Arthropathy (swan-neck)
3. Subcutaneous Nodules: firm, usually over bony prominences or tendons
4. Erythema marginatum - evanescent pink rash, trunk and proximal extremities
5. Chorea (Sydenham's)
   1. Abrupt and purposeless involuntary movements, usually hands / face
   2. May include confusion or delirium [3]
6. Mnemonic
   1. "CANES"
   2. Carditis
   3. Arthritis
   4. Nodules
   5. Erythema
   6. Sydenham's Chorea
7. Minor Symptoms
   1. Arthralgia
   2. Fever
   3. Prolonged PR intervals
   4. Laboratory abnormalities
8. Two major or one major and two minor criteria to make diagnosis of rheumatic fever
9. World Health Organization (WHO) Criteria
   1. Chorea and indolent carditis do not require evidence of antecedent GAS
   2. First episode: as per Jones' Criteria
   3. Recurrent episode: in a patient without established RHD as per first episode
   4. In a patient with estalished RHD: requires 2 minor manifestations + evidence of prior GAS
   5. Or evidence of prior GAS as per Jones' Criteria, but with addition of recent scarlet fever

C. Carditis

1. Pancarditis - any or all layers may be affected
   1. Pericarditis
   2. Myocarditis
   3. Endocarditis (including vasculitis)
2. Valve Disease
   1. Mitral > Aortic (mitral disease found in >80%)
   2. Mitral regurgitation is most common acute lesion
   3. Over time, mixed valvular disease occurs
   4. Mitral stenosis is most commonly seen valve disease in women with RHD
3. Pericarditis, congestive heart failure in more severe cases
4. Gallop beats and pericardial friction rubs are not uncommon
5. A significant portion of atrial fibrillation cases are still related to RHD [4]
6. Echocardiographic screening detects ~10X more RHD than clinical symptoms alone [6]

D. Histopathology

1. Aschoff bodies are characteristic lesion (unclear etiology)
   1. These are clear, whitish areas on organ infarction
   2. Histologically, appear as washed-out, large connective tissue cells within granulomas
2. Non-Bacterial Thrombotic Endocarditis (NBTE)
   1. NBTE lesions extremely common in RHD and cause fusion of commissures.
   2. Fusion most common in mitral valve, second in aorta; rarely pulmonic.
   3. Late stages show rolling, thickening and calcification

E. Diagnosis

1. History
   1. Highly suspicious history occurs in only ~50% of patients with clear RHD
   2. Erythematous rash with pharyngitis
2. Murmurs or other findings characteristic of Rheumatic Fever on examination
   1. Mitral Stenosis (MS) murmur is most common [1]
   2. MS murmer: S1 loud, snapping; Opening Snap follows A2 (diastole)
   3. MS has low pitched, rumbling diastolic murmur (length usually proportional to severity)
   4. Aortic stenosis (usually with aortic regurgitation) may also occur
   5. Atrial Fibrillation
3. Carditis with polyarthritis together are most common findings (44%) [3]
4. Complete blood count - WBC may be quite high; anemia often present
5. Elevated ESR, C-reactive protein
6. High Anti-Streptolysin O Titer (ASO) or DNAse B level or hyaloronidase

F. Treatment [1]

1. Non-specific
   1. Directed at organism and symptoms
   2. Glucocorticoids should be considered for severe acute disease [3]
   3. NSAIDS to control fever
   4. NSAIDS including salicylates do not appear to alter disease course
2. Anti-Streptococcal Therapy
   1. Antibiotics within 9 days of infection (sore throat) substantially reduces risk
   2. Intramuscular 1.2 million units (600,000 units for <27kg) Benzanthine Penicillin G x 1
   3. OR Penicillin V or amoxiillin 500mg (250mg for children) bid or tid x 10 days
   4. OR first generation cephalosporin po x 10 days
   5. OR Erythromycin or vancomycin in penicillin allergic patients
3. Treatment of chorea is symptomatic: prevent patient from harming self
4. Prophylaxis (Long Term Prevention in RHD Patients)
   1. Monthly IM injection of 1.2 mU benzanthine penicillin (at least 5 years)
   2. Alternative prophylaxis: 250mg po Pen V bid or Erythromycin 250mg po bid
   3. All patients at risk for progressive valve damage should receive prophylaxis
5. All patients with valve murmurs should receive pre-procedure antibiotic prophylaxis
6. Mitral Valve Disease
   1. For MS, reduce heart rate to allow improved ventricular filling
   2. Valvuloplasty
   3. Valve replacement
7. Atrial Fibrillation
   1. Rate control and cardioversion as usual
   2. High level anti-coagulation is required

References

1. Carapetis JR, McDonald M, Wilson NJ. 2005. Lancet. 366(9480):155
2. Ledford DK. 1997. JAMA. 278(22):1962
3. Kanabar DJ, Wright A, Marsh MJ. 1996. Lancet. 348:1000
4. Thibault GE. 1995. NEJM. 333(10):648 (Case Discussion)
5. Albert LJ and Inman RD. 1999. NEJM. 341(27):2068
6. Marijon E, Ou P, Celermajer DS, et al. 2007. NEJM. 357(5):470