359 Acute Rheumatic Fever

Question 1

Acute rheumatic fever (ARF) is a multisystem disease resulting from an autoimmune reaction to infection with what bacteria

Answer 1

group A Streptococcus.

Question 2

most common cause of acquired heart disease in children in developing countries

Answer 2

RHD

Question 3

ARF is mainly a disease of children age ____. This pattern contrasts with the prevalence of RHD, which peaks between ____ years

Answer 3

ARF: 5–14 years

RHD: 25 and 40 years

Question 4

ARF and RHD more commonly affects females. True or false

Answer 4

FALSE….

There is no clear gender association for ARF, but RHD more commonly affects females, sometimes up to twice as frequently as males.

Question 5

____ serotype of Group A strep is assoc with ARF

Answer 5

M serotype

Question 6

human leukocyte antigen (HLA) class II alleles, that are associated with susceptibility for ARF (2)

Answer 6

HLA-DR7
HLA-DR4

Question 7

most widely accepted theory of rheumatic fever pathogenesis is based on the concept of ____.

Answer 7

molecular mimicry

Question 8

The most widely accepted theory of rheumatic fever pathogenesis is based on the concept of molecular mimicry, whereby an immune response targeted at these 2 streptococcal antigens also recognizes human tissues.

Answer 8

M protein and the N-acetylglucosamine of group A streptococcal carbohydrate

Question 9

alternative hypothesis for
ARF (apart from molecular mimicry)

Answer 9

proposes that the initial damage is due to streptococcal invasion of epithelial surfaces, with binding of M protein to type IV collagen allowing it to become immunogenic, but not through the mechanism of molecular mimicry.

Question 10

these drugs are effective and lead to more rapid symptom reduction in chorea.
They should be considered in severe or refractory cases.

Answer 10

Corticosteroids commenced at 0.5 mg/kg daily

Question 11

when should 2D echobe performed to determine if there has been progression of carditis.

Answer 11

after 1 month

Question 12

Timing of monitoring of inflammatory markers in ARF

Answer 12

every 1–2 weeks until they have normalized (usually within 4–6 weeks)

Question 13

mainstay of primary prevention for ARF

Answer 13

remains primary prophylaxis (i.e., the timely and complete treatment of group A streptococcal sore throat with antibiotics).

Question 14

If commenced within ____days of sore throat onset, a course of penicillin (as outlined above for treatment of ARF) will prevent almost all cases of ARF that would otherwise have developed

Answer 14

within 9 days

Question 15

mainstay of controlling ARF and RHD

Answer 15

secondary prevention.. long-term penicillin prophylaxis

Question 16

the best antibiotic for secondary prophylaxis for ARF