Rheumatic Fever
Immune mediated reaction to Gr A beta hemolytic Streptococcus, usually after 3 – 6 weeks of sore throat.
Common in children 5- 15 years old and more in females.
Presentation:
Acute rheumatic fever is diagnosed using the Revised Jones Criteria, which consist of clinical and laboratory findings.
Diagnosis requires either 2 major criteria or 1 major and 2 minor criteria; along with evidence of preceding streptococcal infection like scarlet fever, positive throat swab or raised ASOT.
Major criteria:
– Carditis (includes endocarditis/myocarditis/pericarditis, with tachycardia, new murmur or heart failure)
– Polyarthritis (migratory to other joints & self-resolving)
– Sydenham’s chorea
– Erythema marginatum (pink macules with serpiginous border and central clearing)
– Subcutaneous nodules (hard lumps over extensor surfaces)- late sign
– Chorea (Sydenham chorea or St. Vitus dance) or Choreoathetosis- late sign
Minor criteria:
– Fever (temperature > 38 C)
– Raised ESR > 30 mm/h or CRP > 30 mg/L
– Raised WCC
– Prolonged PR interval
– Arthralgias (don’t include if Arthritis already counted)
– Previous Rheumatic fever
Investigations:
– Look for raised WCC, ESR & CRP
– Evidence of Strep infn: Throat swab, ASOT/ Anti DNAase
– Blood culture
– CXR, ECG: look for cardiomegaly or heart failure
– Echocardiogram: Evidence of Pan-Carditis, Percardial Effusion or Valvular heart disease
Treatment
– Acute management includes treatment of Streptococcal infection with Pen V or Erythromycin for 10 days
– Anti-inflammatory drug to minimize cardiac damage
If no carditis: Oral Aspirin for 4 weeks, then taper over 4 weks
If moderate carditis or pericarditis: Aspirin + Prednosolone for 4 weeks, then taper
– Careful use of Diuretics or ACE inhibitors if heart failure
– Bedrest until CRP, ESR and ASOT normalizes
– Consider early referral to paediatric cardiology
Secondary Prophylaxis
– IM Benzathine Penicillin every 3 to 4 weeks
– Oral Penicillin V twice daily (or Erythromycin twice daily if Penicillin allergy)
Duration of prophylaxis:
– Lifelong prophylaxis if Carditis or Acquired Valvular Heart Disease
– Otherwise, at least 5 years after the last episode of Acute Rheumatic Fever OR until 21y age
Prognosis
– Early identification and prophylaxis may avoid cardiac damage
– Risk of cardiac damage increases with each recurrence of rheumatic fever