Rheumatic Fever

Question 1

What is rheumatic fever?

Answer 1

• Acute rheumatic fever is a systemic disease of childhood, often recurrent that follows group A beta hemolytic streptococcal infection
• It is a delayed non-suppurative sequelae to URTI with GABH streptococci.
• It is a diffuse inflammatory disease of connective tissue, primarily involving heart, blood vessels, joints, subcutaneous tissue and CNS

Question 2

Epidemiology?

Answer 2

• Ages 5-15 yrs are most susceptible
• Rare <3 yrs
• Girls>boys
• Common in 3rd world countries
• Environmental factors
  e.g. overcrowding, poor sanitation, poverty
• Incidence more during fall, winter & early spring

Question 3

Organism causes?

When do you see the clinical features - latent period?

Answer 3

group A beta-streptococcus
- There is a latent period of ~3 weeks (1–5 weeks) between the group A streptococcal infection and the appearance of the clinical features of RF

Question 4

Cases of rheumatic fever are often associated with?

Name the URTI?

Answer 4

All cases associated with recent infection (e.g. pharyngitis)
- Antibody and cellular immune response cross-reacts with human connective tissue

Question 5

Pathogenesis of rheumatic fever?

Answer 5

1. Rheumatic fever affect the peri-arteriolar connective tissue
2. It is believed to be caused by antibodycross-reactivity
3. This cross-reactivity is a Type II hypersensitivity reaction and is termedmolecular mimicry
   - Delayed immune response to infection with group. A beta hemolytic streptococci.
4. After a latent period of 1-3 weeks, antibody induced immunological damage occur to heart valves, joints, subcutaneous tissue & basal ganglia of brain

Question 6

Group A beta strep strains that produces rheumatic fever?

Answer 6

M types l, 3, 5, 6,18 & 24

Question 7

Pharyngitis?

Answer 7

produced by GABHS can lead to:
1. acute rheumatic fever
2. rheumatic heart disease
3. post streptococcal glomerulonephritis

Question 8

Skin infection?

Answer 8

produced by GABHS leads to post streptococcal glomerulonephritis only
- It will not result in Rheumatic Fever or carditis

Question 9

Clinical manifestation?

Diagnosis of RHD?

Answer 9

Jones criteria for the diagnosis of acute rheumatic fever
- 2 major criteria
- 1 major & 2 minor criteria along with the absolute requirement
Note: There are 5 major and 4 minor criteria & an absolute requirement for evidence (microbiologic or serologic) of recent GABHS infection

Question 10

Jones major criteria?

Answer 10

JONES
J - joint involvement
O - myocarditis
N - nodules, subcutaneous
E - erythema marginatum
S - sydenham chorea

Question 11

Jones minor criteria?

Answer 11

CAFE PAL
C - CRP increased
A - arthralgia
F - fever
E - elevated ESR

P - prolonged PR interval
A - anamnesis of rheumatism
L - leukocytosis

Question 12

Absolute diagnostic evidence?

Answer 12

1. throat cultures growing GABHS
2. elevated anti-streptolysin O titers

Question 13

Describe arthritis?

Answer 13

• Migratory polyarthritis, involving major joints
• Commonly involved joints-knee, ankle, elbow & wrist
• Occur in 80%, involved joints are exquisitely tender
• In children below 5 yrs arthritis usually mild but carditis more prominent
• Arthritis do not progress to chronic disease

Question 14

Describe carditis?

Answer 14

• Manifest as pancarditis
  e.g. endocarditis, myocarditis and pericarditis - occur in 40-50% of cases
• Carditis is the only manifestation of rheumatic fever that leaves a sequelae & permanent damage to the organ

Question 15

Phases of carditis?

Answer 15

1. Acute phase - valvulitis
2. Chronic phase - fibrosis, calcification & stenosis of heart valves

Question 16

Features of carditis?

Answer 16

1. Consists of either isolated mitral valvular disease or combined aortic & mitral valvular disease
2. Valvular insufficiency: characteristic of both acute & convalescent stages of acute rheumatic fever

Question 17

Sydenhams chorea?

Answer 17

• The choreiform movements affect particularly the head and the upper limbs
• They may be generalized or restricted to one side of the body (hemi-chorea)
• Clinically manifest as-clumsiness, deterioration of handwriting, emotional lability or grimacing of face

Question 18

Epidemiology of Sydenhams chorea?

Answer 18

occurs in children, rare in adults

Question 19

Causes of Sydenhams chorea?

Answer 19

likely due to molecular mimicry, with autoantibodies reacting with brain ganglioside in the basal ganglia
- Chorea eventually resolves completely, usually within 6 weeks

Question 20

Erythema marginatum?

Answer 20

• Unique, transient lesions of 1-2 inches in size
• It consists of erythematous, serpiginous, macular lesions with pale centers that are not pruritic
• Pale center with red irregular margin
• More on trunks & limbs & not on the face & it can be accentuated by warming the skin

Question 21

Erythema marginatum is associated with?

Answer 21

Often associated with chronic carditis

Question 22

Subcutaneous nodules?

Answer 22

• Painless, pea-sized, palpable nodules
• Mainly over extensor surfaces of joints, spine, scapulae & scalp

Question 23

Subcutaneous nodules are associated with?

Answer 23

1. Associated with strong seropositivity
2. Always associated with severe carditis

Question 24

Minor features of rheumatic fever?

Answer 24

1. Fever – Low grade
2. Arthralgia
3. Pallor
4. Anorexia
5. Loss of weight

Question 25

Labaratory findings?

Answer 25

1. High ESR 2. Anemia, leucocytosis 3. Elevated C-reactive protein 4. ASO titre >200. - Peak value attained at 3 weeks, then comes down to normal by 6 weeks 5. Anti-DNAse B test 6. Throat culture-GABH streptococci 7. ECG - prolonged PR interval 8. Echo

Question 26

Echo results?

Answer 26

1. valve edema 2. mitral regurgitation 3. LA & LV dilatation 4. pericardial effusion 5. decreased contractility

Question 27

Ddx for RHD?

Answer 27

Patients with infective endocarditis - present with both joint and cardiac manifestations

Question 28

Differentiating between infective endocarditis vs RHD?

Answer 28

1. blood cultures 2. the presence of associated findings - hematuria, splenomegaly, splinter hemorrhages

Question 29

Treatment of rheumatic fever?

Answer 29

1. bed rest 2. antibiotic therapy 3. anti-inflammatory therapy

Question 30

Antibiotic therapy?

Answer 30

1. 10 days of orally administered penicillin or erythromycin or 2. a single intramuscular injection of benzathine penicillin to eradicate GABHS from the upper respiratory tract - Afterwards, the patient should be started on long-term antibiotic prophylaxis

Question 31

Anti-inflammatory therapy?

Answer 31

1. salicylates, corticosteroids - should be withheld if arthralgia or atypical arthritis is the only clinical manifestation of presumed acute rheumatic fever 2. Acetaminophen can be used

Question 32

Treatment of Patients with typical migratory polyarthritis & with carditis without cardiomegaly or congestive heart failure?

Answer 32

Treatment with oral salicylates - 100 mg/kg/day in 4 divided doses PO for 3-5 days - followed by 75 mg/kg/day in 4 divided doses PO for 4-8 wk

Question 33

Treatment of Patients with carditis & cardiomegaly or congestive heart failure?

Answer 33

1. treatment with corticosteroids 2. Prednisone 2 mg/kg/day in 4 divided doses for 2-6 wk followed by a tapering of the dose that reduces the dose by 5 mg/24 hr every 2-3 days 3. At the beginning of the tapering of the prednisone dose, aspirin should be started at 75 mg/kg/day in 4 divided doses to complete 12 wk of therapy

Question 34

Supportive therapy for patients with moderate to severe carditis?

Answer 34

1. digoxin 2. fluid & salt restriction 3. diuretics & oxygen Note: The cardiac toxicity of digoxin is enhanced with myocarditis

Question 35

Treatment of Sydenham Chorea?

Answer 35

1. Anti-inflammatory agents are usually not indicated 2. Sedatives: phenobarbital (16-32 mg every 6-8 hr PO) is the drug of choice 3. If phenobarbital is ineffective, then haloperidol (0.01-0.03 mg/kg/24 hr divided bid PO) or chlorpromazine (0.5 mg/kg every 4-6 hr PO) should be initiated 4. Long-term antibiotic prophylaxis

Question 36

Primary prevention in rheumatic fever?

Answer 36

10 days course of penicillin therapy - about 30% of patients with acute rheumatic fever do not recall a preceding episode of pharyngitis

Question 37

Secondary prevention of rheumatic fever?

Answer 37

Secondary prevention is directed at preventing acute GABHS pharyngitis in patients at substantial risk of recurrent acute rheumatic fever

Question 38

Who should receive prophylaxis in secondary prevention?

Answer 38

Patients with documented history of rheumatic fever, including those with isolated chorea & those without evidence of rheumatic heart disease MUST receive prophylaxis

Question 39

Secondary prevention in rheumatic fever without carditis? | How long to give Prophylaxis treatment?

Answer 39

at least for 5 year or until age 21 year, whichever is longer

Question 40

Secondary prevention in rheumatic fever with carditis but without residual heart disease (no valvular disease)?

Answer 40

at least for 10 years or well into adulthood, whichever is longer

Question 41

Secondary prevention in rheumatic fever with carditis and residual heart disease (persistent valvular disease)? | How long to give prophylactic treatment for?

Answer 41

at least 10 years since last episode and at least until age 40 years: sometimes lifelong

Question 42

Drugs used in secondary prevention as prophylaxis?

Answer 42

1. penicilin G benzathine - 600,000 U for children, ≤27 kg -1.2 million U for children >27 kg, every 3 wk - intramuscular 2. penicilin V - 250mg twice a day - oral 3. sulfadiazine or sulfisoxazole - 0.5 g, once a day for patients ≤60 lb; 1.0 g, once a day for patients >60 lb - oral

Question 43

Alternative for penicillin allergic patients?

Answer 43

1. Cephalexin 500mg iv stat 2. Azithromycin 500mg iv stat 3. Clarithromycin 500mg iv stat or 4. Clindamycin 900mg iv stat