Acute Rheumatic Fever in Children

Definition: Immunologic sequel of a previous group A beta hemolytic streptococcal infection of pharynx (not of the skin according to some researches). The rheumatogenic strains are M 1, 3, 5, 6, 14, 18, 19 and 24.

Pathogenesis:

  1. Molecular mimicry
  2. Affects brain, heart, joints, and skin
  3. In genetically vulnerable host

Pathogenesis and morphology: Rheumatic fever and Rheumatic heart disease

Epidemiology:

  1. Peak incidence: 5-15 years
  2. Follows pharyngitis by 1 to 5 weeks (~3 weeks)
  3. Incidence: 0.3 to 3%
  4. M=F (Mitral involvement more in females and Aortic more in males)
  5. Incubatuon period: 1-4 weeks after group A streptococcal infection

Diagnosis: Jone’s Criteria (Essential + 2major or 1 major and 2 minor)

A) Major criteria (SPACE)

  1. Subcutaneous nodules (3-5%): Hard, non-tender, small over bony prominences (late manifestation – after 6 weeks) and lasting for weeks
  2. Pancarditis (50-60%): Early manifestation
    • Pathology: Aschoff bodies
    • Pericarditis: Precordial pain, Friction rub on auscultation, ECG ST and T changes, Mitral or Mitral and aortic regurgitation murmurs
    • Myocarditis: Cardiomegaly, Soft S1, S3 gallop, CHF, Carey Coomb’s murmur (Delayed diastolic murmur)
    • Endocarditis: Pansystolic murmur of mitral regurgitation +/- Aortic regurgitation murmur
  3. Arthritis (70-75%): Migratory polyarthritis (Early manifestation)
    • Duration: usually <1 month
    • Usually involves large joints (knees, ankles, elbows and wrists)
    • Migratory: Usually new joints are affected before the previously involved joints improve
  4. Chorea: Sydenham chorea (Late manifestation)
    • Duration: 2-6 weeks
    • 3-4 X more common in females
    • Purposeless movements, emotional lability, motor incoordination and weakness
    • Can involve face, hands and feet
  5. Erythema marginatum
    • Pink, erythematous, non-pruritic macular rash
    • Clear center and serpiginous outline
    • Disappears when cold and reappears when warm
    • Trunk and proximal extremities

B) Minor criteria

  1. Clinical:
    • Fever
    • Arthralgia
    • Previous RHF OR RHD
  2. Lab:
    • Leukocytosis or Elevated ESR > or = 30 mm/hr or CRP > or = 30 mg/L
  3. ECG: Prolonged PR interval

C) Essential criteria: Evidence of recent streptococcal infection –

  1. Increased ASO titer >166 Todd units
  2. Positive throat culture
  3. Recent scarlet fever

Diagnosis:

  • Rheumatic fever: 2 major criteria or 2 minor criteria + 1 major criteria AND Essential criteria
  • Recyrrence: 3 minor criteria AND Essential criteria

Important things not to be missed in history:

History of sore throat, migratory polyarthritis (usually symmetrical and involving large joints), any symptoms of heart failure, neurologic and psychologic symptoms, erythematous rashes, fever, abdominal pain, arthralgia, malaise and epistaxis.

Differential Diagnoses:

  1. Gonococcal arthritis
  2. Juvenile Rheumatoid Arthritis
  3. Mixed Connective Tissue Disease
  4. Reactive Arthritis
  5. Systemic Lupus Erythematosus

Complications:

  1. Recurrent disease: Especially for 1st 5 years after an attack
  2. Rheumatic heart disease
  3. Heart failure
  4. Infective Endocarditis

Treatment:

  1. Bed rest
  2. Streptococcal Eradication: Penicillin procaine 4 lac units i.m BD for 10 days or Erythromycin 40mg/kg/day for 4 days (if penicillin cannot be used due to anaphylaxis)
  3. Arthritis: Aspirin  full dose (90-120 mg/kg/day in 4 divided doses) for 10 weeks and tapering in next 2 weeks
  4. Carditis: Corticosteroid/Prednisolone
    • First 3 weeks: 60mg/kg/day (>20 kg), 40 mg/kg/day (<20kg)
    • 4th week: 50mg/day
    • 5th week: 40mg/day
    • Upto 12th week: Reduction by 5mg/week
  5. Chorea: Phenobarbitone 30mg thrice daily

Prevention:

  1. Primary: Identification of streptococcal sore throat and treatment with penicillin
  2. Secondary:
    • Benzathine penicillin 1.2 mega (million) units im every 3 weeks
    • Continue lifelong or till the age of 35 years or for 5 years from the last attack

About the Author

Sulabh Shrestha
Intern doctor and Medical Blogger Sulabh Shrestha

1 Comment on "Acute Rheumatic Fever in Children"

  1. was really helpful…:-)

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