0:00

Let's talk about classic Sydenham's Chorea,

0:02

which has been forgotten in the United States

0:04

due to the low incidence of rheumatic fever.

0:08

But people with a choreoform acute presenting

0:13

disorder will often have abnormalities

0:15

of the putamen. You may see necrosis,

0:18

you may see hemorrhage.

0:19

You may simply see something that looks like

0:21

an infarction, and prion-mediated diseases,

0:24

you'll just see signal alteration that

0:26

does nothing except simply sit there.

0:29

Although in prion disorders,

0:30

it's more often bilateral than it is unilateral.

0:34

Now, people with Sydenham's Chorea

0:36

of classic etiology, namely rheumatic fever,

0:38

may also have thromboembolic changes due to

0:41

vegetations that have migrated into the brain

0:45

through vascular methods or channels.

0:48

Chorea occurs in 26% of patients

0:50

with rheumatic fever,

0:51

and Sydenham's Chorea is still the most common

0:55

cause of acute Chorea in children worldwide.

0:58

Recent outbreaks of rheumatic fever

1:00

with Chorea have been reported

1:02

in the United States and in Australia.

1:06

The typical age of onset of Sydenham's Chorea

1:08

is about eight to nine years of age,

1:10

but very rare below age five.

1:13

You can also see a Sydenham's Chorea-like

1:16

syndrome with blunt force trauma.

1:19

I mentioned this happened to my father.

1:20

He was struck by a car at age 10 and developed

1:23

for about a year and a half.

1:24

sudden-onset Sydenham's-type Chorea symptoms.

1:28

Typically, patients develop this disease four to eight weeks

1:31

after an episode of group A beta-hemolytic strep.

1:34

so-called GABH strep with pharyngitis,

1:38

Sydenham's Chorea rapidly becomes generalized,

1:41

but 20% of patients remain with hemichorea.

1:45

Muscular tone is decreased and

1:47

in less than 2% of cases,

1:49

this may cause patients to become bedridden.

1:52

This is known as Chorea paralytica.

1:55

60% to 80% of patients with this type of

1:59

Chorea have cardiac involvement,

2:01

particularly mitral valve dysfunction,

2:04

whereas these rheumatic fever patients

2:06

have arthritis 30% of the time.

2:09

In about 20% of Sydenham's Chorea patients from

2:12

rheumatic fever, Chorea is the absolute and only finding.

2:17

The pathogenesis of Sydenham's Chorea

2:19

may be related to molecular mimicry between

2:23

streptococcal and CNS antigens,

2:25

causing self-attack of the brain.

2:28

This beta-hemolytic strep infection leads to the

2:31

formation of cross-reactive antibasal ganglia

2:34

antibodies in genetically predisposed patients.

2:37

So, it is the BG and the putamen that

2:40

are attacked accidentally.

2:42

Sydenham's Chorea is commonly a self-limited

2:45

disorder with spontaneous remission after

2:48

a course of eight to nine months.

2:49

And that's also true in the

2:51

traumatic variety as well.

2:53

Prospective studies have shown that up to 50% of

2:56

patients may have persistent Chorea

2:58

after a follow-up of two years,

3:00

and recurrences of Sydenham's Chorea are also

3:03

reported in up to 50% of patients.

3:06

The most important consideration in the treatment

3:08

of patients with SC or Sydenham's Chorea is

3:12

secondary prophylaxis with penicillin or sulfur

3:15

drugs for those who have a penicillin

3:17

allergy up to 21 years of age.

3:19

In the next section,

3:21

we'll talk a little bit about autoimmune choreas.