Rheumatic Fever

Question 1

Define rheumatic fever and rheumatic heart disease

Answer 1

An inflammatory multisystem disorder that arises as a delayed complication of infection of the upper respiratory tract (pharyngeal/SORE THROAT) with beta haemolytic streptococci

Chronic rheumatic heart disease = scarring and chronic inflammation of the heart and valves → heart failure, murmurs, and damage to the valves

Question 2

Aetiology of rheumatic fever

Answer 2

Type 2 hypersensitivity
Pharyngeal infection with Lancefield group A beta-haemolytic streptococci triggers rheumatic fever 2-4weeks later.
An antibody to the cell wall of the streptococcus cross-reacts with valve tissue (antigenic mimicry) and may cause permanent damage to the heart valves
Tends to recur unless prevented.

Question 3

Risk factors for rheumatic fever

Answer 3

Age (4-9yrs)
Sex - Females preponderance in mitral stenosis
Severity of the infection and magnitude of immune response
poverty
overcrowded living quarters
family history of rheumatic fever (specific HLA class II alleles associated with disease)
D8/17 B cell antigen positivity

Question 4

Symptoms of rheumatic fever

Answer 4

2-5 weeks after a Group A beta-haemolytic streptococci infection

Malaise
Fever, malaise, anorexia
Joint pain and swelling: large joint polyarthritis
Reduced movement
Breathlessness, chest pain, palpitations (carditis)
Rash

Question 5

Criteria for rheumatic fever

Answer 5

Jones criteria: 2 major OR 1 major + 2 minor

Major:
- Carditis (tachycardia, aortic/mitral regurgitations, Carey Coombs murmur, pericardial rub, CCF, cardiomegaly, conduction, apical systolic murmur)
- Arthritis (flitting polyarthritis, usually in larger joints)
- Subcutaneous nodules (small, mobile, painless nodules on the joints and spine)
- Erythema marginatum (Geographical-type rash with red, raised edges and clear centre, mainly found on the trunk, thighs and arms)
- Sydenham’s chorea (involuntary semi-purposeful movements). May be preceded be emotional lability and uncharacteristic behaviour or slurred speech

Minor:
- Fever
- Raised ESR or CRP
- Arthralgia
- Prolonged PR interval and QT interval
- Previous rheumatic fever

Question 6

Investigations for rheumatic fever

Answer 6

Throat swab/culture: growth of beta-haemolytic group A strep
Rapid antigen testing: +ve for group A strep
ECG: prolonged PR/QT, evidence of pericarditis

ESR/CRP: raised
FBC: raised WCC
Blood cultures
ASO titre: raised/rising

CXR: chamber enlargement, CHF
Echo: valve disease, regurgitation, pericardial effusion, chordal thickening
Histology: Aschoft + antischkov myocytes

Question 7

Management for rheumatic fever

Answer 7

1. Admit
2. A-E assessment
3. Supportive:
   - Bed rest until CRP is normal for 2 weeks
   - Start with paracetamol until diagnosis is confirmed → High-dose Aspirin (suppresses the inflammatory response of the joints and heart) or NSAIDs
4. Abx e.g. benzathine benzylpenicillin single dose IM
   - amoxicillin (alternative); azithromycin (pen-allergic)
5. Consider other presentations
6. CCF, cardiomegaly, 3rd degree heart block → corticosteroids
   - If the fever and inflammation does NOT resolve rapidly → Corticosteroids
   - Sydenham’s chorea → haloperidol, diazepam
7. Prophylaxis → monthly injections of benzathine penicillin (every 4 weeks)
   - Until 10 years after the last episode OR until the age of 21 years (OR lifelong if severe valve disease)
   - Surgical treatment with valve repair or replacement may be required

Question 8

Complications of rheumatic fever

Answer 8

Valve disease (60-80% acute to chronic)
- Mitral (70%)
- Aortic (40%)
- Tricuspid (10%)
- Pulmonary (2%)
Rheumatic heart disease (30-50%)

Question 9

Prognosis for rheumatic fever

Answer 9

• Without treatment, symptoms resolve within several weeks BUT can progress to rheumatic heart disease
• Symptoms resolve within several weeks with treatment
• Cardiac inflammation will lasts weeks-months
• Patients with ARF should expect to make a complete recovery from the arthritis, fever, and chorea
• Risk of repeated episodes