This document discusses rheumatic fever and rheumatic heart disease. It notes that susceptibility to rheumatic fever is partly hereditary, with certain HLA alleles being associated with increased or decreased susceptibility. Initial damage is caused by streptococcal bacteria invading epithelial tissues, though not through molecular mimicry. Common symptoms include chorea, indolent carditis, and valvular damage, which is a hallmark of rheumatic heart disease. Prolonged PR interval and softening of the first heart sound may also be seen. While bed rest was once recommended, medications are now preferred to control symptoms, and antibiotics are given long-term to prevent recurrence.

3. Unfortunately such a decline was not replicated in developing countries,
where these diseases continue unabated.

7. • Susceptibility to ARF is an
inherited characteristic， with
44% concordance in monozygotic
twins compared to 12% in
dizygotic twins,
• Heritability more recently
estimated at 60%.
• HLA-DR7 and HLA-DR4， appear
to be associated with
susceptibility，
• other class II alleles have been
associated with protection (HLA-
DR5, HLA-DR6， HLA-DR5 1,
HLA-DR52 and HLA-DQ )

8. .
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.

11. Chorea and indolent
Carditis， which may
follow prolonged latent
periods lasting up to
6 months.

21. VALVULAR DAMAGE IS THE HALLMARK
OF RHEUMATIC CARDITIS

22. CAREYCOOMB

26.  Myocardial inflammation may affect electrical
conduction pathways, leading to P-R interval
prolongation (first-degree atrio ventricular block or
rarely higher level block) and
 softening of the first heart sound.

27. PROLONG PR INTERVAL
NORMAL SINUS RHYTHM
FIRST DEGREE HEART BLOCK

45. Traditional
recommendations
for long-term bed
rest, once the
cornerstone of
management，are
no longer widely
practiced.
Medications to control the
abnormal movements do
not alter the
duration or outcome of
chorea. Milder cases can
usually be managed
by providing a calm
environment. In patients
with severe chorea，
carbamazepine or sod i um
valproate is preferred to
haloperidol.

48. Best antibiotic for
secondary prophylaxis
is benzathine penicillin
G delivered every 4
weeks.