Rheumatic fever

Question 1

What is rheumatic fever?

Answer 1

Rare autoimmune complication that develops 2-4 weeks after a bacterial throat infection (Scarlet fever -Streptococcus pyogenes).

Question 2

How does rheumatic fever occur?

Answer 2

2-4 weeks after a group A streptoccocus infection (scarlet fever), auto-antibodies are generated that not only target the streptoccocus but that also cross-react with the endocardium leading to valvular disease. This is known as molecular mimicry.

Question 3

Jones criteria for rheumatic fever?

Answer 3

Diagnostic criteria:
recent streptococcal infection
2 major criteria
1 major with 2 minor criteria

Major criteria
- arthritis
- pancarditis (affects all layers of the myocardium, however endocardial inflammation may predominate causing valvulitis. This may manifest clinically as a tachycardia, new murmur, or a new conduction defect)
- erythema marginatum (ink/red, nonpruritic rash involving mainly the trunk, thighs and arms)
- Sydenham’s chorea (neurological disorder consisting of abrupt, non-rhythmic, involuntary movements along with muscular weakness and emotional disturbance)
- subcutaneous nodules (firm, mobile painless lesions)

Minor criteria
- raised ESR or CRP
- pyrexia
- arthralgia (not if arthritis a major criteria)
- prolonged PR interval

Question 4

IVx for rheumatic fever?

Answer 4

ECG (prolonged PR interval)
Bloods
Blood cultures (r/o sepsis)
Proof of recent streptococcal infection: anti-streptococcal serology (ASOT), throat swab or rapid antigen or molecular tests.
CXR (may show HF)
Echo (valvular abnormalities)

Question 5

Management of rheumatic fever symptoms?

Answer 5

Abx: oral penicillin V/phenoxymethylpenicillin 10 day course (treat group A strep)

anti-inflammatories: NSAIDs are first-line

treatment of any complications that develop e.g. heart failure.

Sydenham’s chorea -self-limiting, however Haloperidol or Diazepam may be used for distressing symptoms or risk of harm.

Erythema marginatum is temporary and doesn’t require treatment, although antihistamines can help with pruritus.

Valvular complications may require surgical intervention.

Question 6

Complications of rheumatic fever?

Answer 6

Valvular abnormalities
e.g. MS, MR, AR, AS, TR