Rheumatic fever

Question 1

Outline the pathophysiology of rheumatic fever (RF)

Answer 1

1. Pharyngeal infection with Lancefield group A B-haemolytic streptococci
2. Antibody production (2-4wks) to the carbohydrate cell wall of bacteria
3. Antibody cross-react with self-tissue (antigenic mimicry, 2% population)

Question 2

Outline the signs/ symptoms/ investigations within the criteria for diagnosis

Answer 2

Revised Jones criteria;

• Evidence of Lancfield group A B-haemolytic streptococcal infection;
  
  • Positive throat culture
  • Rapid streptococcal antigen test +ve
  • Elevated/ rising streptococcal antibody titre (ASO or DNase B titre)
  • Recent scarlet fever
• Major criteria (JONES);
  
  • Joints (migratory polyarthriis)
  • O Carditis (new murmuer)
  • Nodules (subcutaneous)
  • Erythema marginatum (rash)
  • Sydenham’s chorea (St Vitus’ dance)
• Minor criteria (PEACE);
  
  • Prolonged PR interval
  • ESR elevated
  • Arthralgia
  • CRP elevated
  • Elevated temperature

Requires;

• Evidence of Lancfield group A B-haemolytic streptococcal infection
• • 2major/ 1major & 2minor criteria

Question 3

How do you manage RF?

Answer 3

• Bed rest
• Benzylpenicillin (then penicillin)
• Analgesia