Turner Syndrome - Kual L1

Question 0

What percentage of Turner Syndrome patients are phenotypically female?

Answer 0

100%

Question 1

What is required to make a diagnosis of Turner Syndrome?

Answer 1

Clinical: physical features consistent with the syndrome
short stature, webbed neck, gonadal dysgenesis or
insufficiency, etc.

Cytogenetic: Missing all or part of one copy of the second sex
chromosome

Question 2

Under what conditions might a Turner Syndrome patient have Y-chromosome material?

Answer 2

Mosaicism - for example 45 X / 46 XY

or

45 X plus some fragments of the Y chromosome (called a marker)

Question 3

In the case of a marker Y chromosome in Turner syndrome, what is a possible complication?

Answer 3

12% risk of gonadoblastoma

Question 4

List some key physical findings of Turner Syndrome

Answer 4

Eyes: inner canthal folds, ptosis, blue sclera
Ears, Nose, Mouth: Prominent auricles, low-set ears; high narrow
palate; small mandible
Neck: Webbing, low posterior hairline
Chest: broad, widely spaced nipples, pectus excavatum (sunken chest)
Skeleton: Cubitus valgus, short 4th metacarpal, Madelung deformity scoliosis

Question 5

How does the webbed neck seen in TS arise and what other anomaly should be investigated when webbed neck is present?

Answer 5

Webbed neck is residual as a result of cystic hygromas and lymphedema in the fetus

Since the cystic hygromas are a result of heart defects (outflow track is common) the heart should be checked.

Question 6

What are some cardiovascular abnormalities seen in TS?

Answer 6

16% bicuspid valve defect (seen in 37% of those with neck webbing)
11% coractation of the aorta
13% partial anomalous pulmonary venous connection
rare - aortic dilation, dissection (fatal), rupture

Question 7

What is the ekg finding in TS when heart anomalies are present?

Answer 7

QTc prolongation

Question 8

Why is hypertension especially dangerous for patients with TS?

Answer 8

aortic dissection / rupture

Question 9

What are common ear defects in TS patients?

Answer 9

Otitis media leading to conductive hearing loss

Sensorineural hearing loss

Question 10

What are the common renal issues in pts with TS?

Answer 10

34-40% have structural kidney abnormalities
frequency varies with karyotype
45, X –> more likely to have structural kidney abnormalities
karyotypes with structurally abnormal X —> collecting system abnormalities