Turner Syndrome - Kual L1 Flashcards
What percentage of Turner Syndrome patients are phenotypically female?
100%
What is required to make a diagnosis of Turner Syndrome?
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
Under what conditions might a Turner Syndrome patient have Y-chromosome material?
Mosaicism - for example 45 X / 46 XY
or
45 X plus some fragments of the Y chromosome (called a marker)
In the case of a marker Y chromosome in Turner syndrome, what is a possible complication?
12% risk of gonadoblastoma
List some key physical findings of Turner Syndrome
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
How does the webbed neck seen in TS arise and what other anomaly should be investigated when webbed neck is present?
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.
What are some cardiovascular abnormalities seen in TS?
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
What is the ekg finding in TS when heart anomalies are present?
QTc prolongation
Why is hypertension especially dangerous for patients with TS?
aortic dissection / rupture
What are common ear defects in TS patients?
Otitis media leading to conductive hearing loss
Sensorineural hearing loss
What are the common renal issues in pts with TS?
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