Rheumatic Fever Flashcards
Define Rheumatic Fever?
An inflammatory multisystem disorder, occuring following group A beta-haemolytic streptococci (GAS) infection
What is the aetiology of Rheumatic Fever?
Pharyngeal infection with Lancefield group A beta-haemolytic streptococci triggers rheumatic fever 2-4 weeks later in the susceptible 2% of the population
An antibody to the carbohydrate cell wall (GAS antigens) of the streptococcus cross-reacts with valve tissue (antigenic mimicry) and may cause permanent damage to the heart valves
What are the risk factors for Rheumatic Fever?
Genetic susceptibility
Malnutrition
Poverty
What is the epidemiology of Rheumatic Fever?
Common in developing countries but increasingly rare in the WEST
Peak incidence between 5 and 15 years
Mean Incidence: 19/100,000
When do symptoms present in Rheumatic Fever?
2-5 weeks after pharyngeal GAS infection
What are the general presenting symptoms of Rheumatic Fever?
Malaise
Fever
Anorexia
What are the symptoms in the joints for Rheumatic Fever?
Painful, swollen
Reduced movement/function
What are the cardiac symptoms of Rheumatic Fever?
Breathlessness
Chest Pain
Palpitations
How is diagnosis of Rheumatic Fever made?
Using the revised Jones criteria
What is the Jones Criteria?
There must be evidence of recent strep infection + 2 major criteria
OR
1 major + 1 minor criteria
What are some examples of stuff that would be classified as Evidence of GAS infection?
Positive throat culture but usuall negative by the time symptoms occur
Rapid streptococcal antigen test +ve
Elevated/rising streptococcal antibody titre
Recent scarlet fever
What is the major criteria in the Jones Criteria for diagnosis of Rheumatic Fever?
CASES
Carditis- Tachycardia, murmurs, pericardial rub, cardiomegaly, conduction defects
Arthritis- usually affects larger joints
Subcutaneous nodules- small firm painless nodules seen on extensor surfaces, joints and tendons
Erythema Marginatum- Geographical-type rash with red, raised edges and clear centre mainly on trunk and proximal limbs
Sydenham’s Chorea - rapid involuntay irregular movements with flowing/dancing quality
What is the minor criteria in the Jones Criteria to diagnose Rheumatic Fever?
PRAPP
Pyrexia
Raised ESR/CRP
Arthralgia (only if arthritis not present as major criteria)
Prolonged PR interval (only if carditis not present as major criteria)
Previous rheumatic fever
What investigations would you do for Rheumatic Fever?
Bloods
Throat Swab
ECG
Echocardiogram
What bloods would you do for Rheumatic Fever?
FBC (inc WCC)
ESR/CRP
Rising antistreptolysin O titre
