Revision - Kawasaki Disease & Rheumatic Fever

Question 1

What is the diagnosis of Kawasaki disease based on?

Answer 1

The American Heart Association diagnostic criteria

Question 2

What is the AHA diagnostic criteria for Kawasaki disease?

Answer 2

Presence of fever (usually ≥39°C) for at least 5 days, plus at least 4 out of 5 key features:

1) Mucositis: erythema and cracking of the lips, strawberry tongue and/or oral erythema

2) Conjunctivitis: bilateral conjunctivitis without exudate

3) Rash: maculopapular, erythroderma or erythema multiforme

4) Peripheral changes: erythema, oedema and/or desquamation of the hands and feet

5) Cervical lymphadenopathy

Question 3

Location of lymphadenopathy in Kawasaki disease?

Answer 3

Cervical

Question 4

What can happen to hands and feet in Kawasaki disease?

Answer 4

Red palms of the hands and the soles of the feet which later peel

Question 5

Which phase of Kawasaki disease is the highest risk period for developing cardiac complications?

Answer 5

Subacute phase (2-4w from fever onset)

Question 6

What investigation can be done to exclude Streptococcus infection?

Answer 6

Anti-streptolysin O titre (ASOT): to exclude group A streptococcal infection

Question 7

Mx of Kawasaki disease?

Answer 7

High dose aspirin + IV immunoglobulins

Question 8

Role of aspirin in Kawasaki disease?

Answer 8

Reduce risk of coronary artery aneurysms & thrombosis

Question 9

How long is aspirin given for in Kawasaki disease?

Answer 9

High dose aspirin given until fever has resolved for 48h, then low dose given for approx 6 weeks

Question 10

What is Reye’s syndrome?

Answer 10

A rare acute encephalopathy associated with liver failure.

Question 11

Role of IVIG in Kawasaki disease?

Answer 11

Infusion within the first 10 days of illness can reduce the incidence of coronary artery aneurysms .

Question 12

When should improvement be seen after intiating treatment in Kawasaki disease?

Answer 12

Within 36 hours.

Note - A second dose of IVIG may be given if an improvement is not seen.

Question 13

What are some complications of Kawasaki disease?

Answer 13

1) Coronary artery aneurysms

2) Myocarditis/pericarditis

3) Arrhythmias

4) Valvular disease (e.g. mitral regurgitation)

5) Coronary artery thrombosis/myocardial infarction

6) Sudden cardiac death

Question 14

What is the danger of a coronary artery aneurysm in Kawasaki disease?

Answer 14

Can rupture –> cardiac tamponade

Question 15

What bacteria is implicated in rheumatic fever?

Answer 15

GAS

Question 16

What is rheumatic fever?

Answer 16

A systemic inflammatory disorder that arises as a result of infection with GAS.

Question 17

How soon after Strep infection can rheumatic fever develop?

Answer 17

2-6 weeks

Question 18

How does initial Strep. pyogenes infection typically present?

Answer 18

1) Pharyngitis (sore throat)

or

2) Cellulitis

Question 19

How is strep infection more likely to present in hot countries?

Answer 19

As skin infection instead of pharyngitis

Question 20

What criteria is used for diagnosing rheumatic fever?

Answer 20

Jones criteria

Question 21

What does the Jones criteria state about the diagnosis of rheumatic fever?

Answer 21

There must be evidence of recent GAS infection plus either;

• 2 major criteria
• 1 major criteria and 2 minor criteria

Question 22

Give some evidence of a recent group A strep infection

Answer 22

1) Positive throat swab

2) Positive rapid streptococcal antigen test

3) Raised streptococcal antibody titre (ASO or DNAse)

4) Recent episode of scarlet fever

Question 23

What are the 5 major criteria for rheumatic fever?

Answer 23

1) Polyarthritis (joint involvement)

2) Carditis & valvulitis (heart involvement)

3) Sydenham’s chorea (nervous system involvement)

4) Erythema marginatum (skin involvement)

5) SC nodules (skin involvement)

Question 24

typical symptoms of rheumatic fever?

Answer 24

• fever
• joint pain
• rash
• chorea
• SOB
• nodules

Question 25

How can rheumatic fever affect the joints?

Answer 25

Affects large joints - hot, swollen, painful joints. ‘Migratory polyarthritis’ - different joints become inflamed and improve at different times.

Question 26

What is the most common symptom of rheumatic fever?

Answer 26

Polyarthritis (80%)

Question 27

What may aspiration of synovial fluid in polyarthritis caused by rheumatic fever show?

Answer 27

Sterile inflammation with no organisms present

Question 28

What is the most significant manifestation of rheumatic fever?

Answer 28

Carditis

Question 29

What clinical features can carditis caused by rheumatic fever cause?

Answer 29

1) pericarditis 2) myocarditis 3) endocarditis

Question 30

How can myocarditis present?

Answer 30

Congestive heart failure: SOB, orthopnoea, PND, cardiogenic shock

Question 31

What is the most commonly affected valve in rheumatic fever?

Answer 31

Mitral valve

Question 32

How does rheumatic fever typically affect valves?

Answer 32

In an attack of rheumatic fever, valve incompetence (i.e. regurgitation) is more likely to develop than valve stenosis. Valve stenosis tends to develop as a feature of chronic disease many years later.

Question 33

How soon after initial streptococcal infection does Sydenham’s chorea appear?

Answer 33

2-6m later

Question 34

What is Sydenham’s chorea sometimes preceded by?

Answer 34

Emotional lability or behaviour which is out of character for the patient.

Question 35

What are the 2 key skin findings in rheumatic fever?

Answer 35

1) SC nodules (only present with severe carditis) 2) Erythema marginatum rash --> look up pic!

Question 36

Where are subcutaneous nodules typically found in rheumatic fever?

Answer 36

Extensor surfaces

Question 37

What are the 4 minor criteria for rheumatic fever?

Answer 37

1) Raised ESR or CRP 2) Pyrexia (typically >39 degrees) 3) Polyarthralgia i.e. pain present in multiple joints (this is not included in the criteria if polyarthritis is already present) 4) Prolonged PR on ECG 5) History of rheumatic fever

Question 38

Arthritis vs arthralgia?

Answer 38

Arthritis is an inflammatory condition that causes joint pain. Arthralgia is joint pain.

Question 39

Mneumonic for rememebering major criteria for rheumatic fever: JONES

Answer 39

J - joint arthritis O - organ inflammation such as carditis N - nodules E - erythema marginatum rash S - sydenham's chorea

Question 40

What 2 ECG findings may be present in rheumatic fever?

Answer 40

1) Prolonged PR 2) Tachycardia N.B. may also be signs of pericarditis or myocarditis

Question 41

Investigations in rheumatic fever?

Answer 41

1) ECG 2) Vital signs (fever) 3) Throat swabs for GAS 4) Rapid streptococcal antigen test (RAST) 5) Anti-streptococcal antibodies 6) Blood tests: FBC, ESR, CRP, troponin, rheumatoid factor, anti-CCP

Question 42

What are the 2 most common antibody tests used for rheumatic fever?

Answer 42

1) anti-streptolysin (ASO) 2) anti-DNAse B

Question 43

When may troponin be raised in rheumatic fever?

Answer 43

Myocarditis

Question 44

Role of CXR in rheumatic fever?

Answer 44

Rule out HF

Question 45

Management of rheumatic fever can be divided into acute management and prophylaxis. What does acute management of rheumatic fever involve?

Answer 45

1st line --> supportive, bed rest Abx --> single dose of IV benzylpenicillin followed by oral penicillin V (phenoxymethylpenicillin) for 10d High dose aspirin Steroids (if carditis expected)

Question 46

What Abx are indicated in acute rheumatic fever?

Answer 46

Single stat IV dose of benzylpenicillin, followed by 10d oral penicillin V. To kill GAS

Question 47

Role of high dose aspirin or other NSAIDs in acute rheumatic fever?

Answer 47

To manage inflammation and reduce symptoms such as fever, joint pain, and swelling.

Question 48

Importance of bed rest in rheumatic fever?

Answer 48

Rheumatic fever is one of the few conditions where bed rest is recommended as first-line treatment, even if the patient feels well. This is even more important in cases of suspected active myocarditis (indicated by abnormalities seen on the echocardiogram and a raised ESR), where limitation of exercise is strongly advised.

Question 49

Is bed rest recommended in myocarditis?

Answer 49

Yes

Question 50

After the initial attack, the child should be followed up regularly and prophylactic treatment started to reduce the chance of any future attacks. What is the current recommended first-line prophylactic treatment for rheumatic fever?

Answer 50

Benzathine penicillin G, given every 4 weeks as an IM injection.

Question 51

What is the most common valve lesion in rheumatic fever overall?

Answer 51

Mitral regurgitation

Question 52

What is the most common long-term cardiac complication of rheumatic fever?

Answer 52

Mitral stenosis

Question 53

What 3 factors can trigger a relapse of rheumatic fever?

Answer 53

1) reinfection with GAS 2) pregnancy 3) COCP

Question 54

Which medication can trigger a relapse of rheumatic fever?

Answer 54

COCP

Question 55

What is the most common valvular abnormality in Kawasaki disease?

Answer 55

Mitral regurg

Question 56

What 3 conditions can a strawberry tongue indicate?

Answer 56

1) Scarlet fever 2) Kawasaki disease 3) Toxic shock syndrome