Rheumatic Fever

Question 1

what is the definition of rheumatic fever

Answer 1

inflammatory multisystem disorder
autoimmune
following a beta-haemolytic streptococci infection

Question 2

what group of strep is a beta-haemolytic streptococci infection

Answer 2

group A strep

Question 3

what is the GAS (a beta-haemolytic strepococci infection) which causes rheumatic fever

Answer 3

s. pyogenes

initially a throat infection

Question 4

what is the aetiology of rheumatic fever

Answer 4

initially a streptococcal pharyngeal infection
genetic susceptibility may be present
molecular mimicry plays an important role in initiation of tissue injury (antibodies against GAS antigens cross react with host antigens)

Question 5

what is the epidemiology of rheumatic fever

Answer 5

peak incidence 5-15yrs
mean incidence is 20 per 100,000PA
common in far east, middle east, eastern europe, south america
less common in west

Question 6

what history is associated with rheumatic fever

Answer 6

presentation 2-5wks post GAS infection
general
-fever
-malaise
-anorexia
cardiac
-SOB
-chest pain
-palpitations
joints
-painful
-swollen
-impaired function

Question 7

what criteria is used for examination in suspected rheumatic fever

Answer 7

duckett jones criteria

Question 8

what constitutes diagnosis using the duckett jones criteria

Answer 8

2 or more major criteria

1 major and 2 or more minor criteria

Question 9

what are the duckett jones major criteria for rheumatic fever

Answer 9

CASES

Carditis
-new murmur(Carey Coombs murmur) a mid diastolic murmur due to mitral valve inflammation
-pericarditis
-pericardial effusion/rub
-cardiomegaly
-HF
Arthritis
-migrating polyarthritis
-swelling, redness, tenderness of large joints
Sydenham's Chorea
-rapid, involuntary, irregular movements
-slurred speech
-more common in females
Erythema marginatum(20% of cases)
-short periods of red rashes with raised edges
-present on trunk and proximal limbs
-form crescent/ring-shaped patches
Subcutaneous nodules
-small, firm, painless nodules
- on joints and tendons

Question 10

what are the duckett jones minor criteria for rheumatic fever

Answer 10

PEACH FEVER

Prolonged PR and QT intervals (if carditis not present)
ESR raised
Arthralgia (if arthritis or present)
Acute phase reactants raised (WCC, ESR, CRP)
CRP raised
History of previous RF/rheumatic heart disease/recent streptococcal infection

FEVER

Question 11

what would indicate recent streptococcal infection

Answer 11

positive throat cultures

raised antistreptolysin O titre

Question 12

what investigations would be performed in suspected rheumatic fever

Answer 12

1 bloods
-FBC(raised WCC)
-raised ESR/CRP
-raised antistreptolysin O titre
2 throat swab
-culture for GAS infection
-streptococcal antigen test
3 ECG
-'saddle shaped' ST elevation and PR segment depression(feature of pericarditis)
-arrhythmias
4 echo
-pericardial effusion
-myocardial thickening/dysfunction
-valvular dysfunction

Question 13

what is the management for rheumatic fever

Answer 13

Conservative
-strict bed rest for 4wks
Medical
-anti-inflammatories (high dose aspirin, corticosteroids if severe)
-antibiotics (oral penicillin V for 10 days for strep infection, long term antibiotics to prevent recurrence such as benzathine penicillin G IM every 4wks)
-treat carditis by treating HF (diuretics)
-treat chorea with diazepam/haloperidol
Surgical
-only if medical therapy fails

Question 14

what complications are associated with rheumatic fever

Answer 14

recurrence
-more common with cardiac damage
-precipitated by streptococcal infection
chronic rheumatic valvular disease
-more common when acute RF presents with carditis
-scarring, deformation, dysfunction of mitral/aortic valves after 10-20yrs

Question 15

what is the prognosis associated with rheumatic fever

Answer 15

acute RF may last 3months if untreated

females more likely to develop mitral stenosis