Turner Syndrome

Question 1

What is the inheritance for TS?

Answer 1

Sporadic

Question 2

What is the recurrence risk for TS?

Answer 2

<1%

Question 3

What gene is responsible for short stature in TS?

Answer 3

Deficiency of one copy of SHOX (short stature homeobox gene) on Xp considered to have role in short stature

Question 4

What karyotypes can be present in TS?

Answer 4

1. 50-60% 45,X
2. 20-25% 45,X/46,X(X)* structural defect of one X
3. 10-20% 45,X/46,XX mosaic, often only short stature

Question 5

What are the associated medical findings in TS?

Answer 5

1. Short neck – webbing; low posterior hair line
2. Prominent post. rotated ears with upturned ear lobes, ptosis, micrognathia
3. Cubitus valgus
4. Short 4th, 5th metacarpals (50%)
5. Disproportionately short legs
6. Hyperconvex nails
7. Cardiac
   a) Bicuspid aortic valve
   b) Coarctation of aorta
   c) HLH with heart failure
   d) Risk of aortic dilatation 9%; aortic dissection uncommon in childhood
   e) Hypertension
8. Musculoskeletal
   a) Hip dysplasia (5-10%)
   b) Scoliosis and/or kyphosis (10-20%)
9. Renal structural abnormalities (> 60% )
   a) horseshoe kidney
   b) ectopic kidney
   c) aplasia
   d) double collecting system
   e) UPJ obstruction
10. ENT
    a) Chronic otitis
    b) Conductive hearing loss common
11. Dermatology
    a) Dysplasia
    b) Keloids
    c) Vitiligo
12. Autoimmune
    a) Obesity
    b) hyperlipidemia
    c) Hyperinsulinism
    d) Thyroiditis
    e) IBD
    f) Celiac Disease
13. Endocrine
    a) Short stature for family history. May otherwise be normal. 50% are <5%
    by age 18 mos.;75% are <5% by age 3.5 yr.
    b) Delayed Puberty, infertility
    c) Menarche 1-3%

Question 6

What is the neonatal presentation of TS?

Answer 6

1. Fetus: Edema, hydrops
   a) 98% spontaneous abortion
2. Newborn:
   a) puffy edema of feet, hands
   b) nuchal webbing
   c) broad chest with widespaced nipples; left sided cardiac defect

Question 7

What are the developmental outcomes of TS?

Answer 7

1. NONVERBAL LEARNING DISABILITIES
o Generally normal IQ
o verbal and language IQ > performance IQ
o many are successful in college
2.  Scattered profile of specific learning disabilities
o visual spatial organization
o nonverbal problem solving (math)
o visual – motor tasks
o social cognition (subtle clues)
3. ADHD (24%)
4.  Increased depression, anxiety
5. 50% experience hearing loss
a) conductive HL, chronic OM
b) sensorineural HL > age 6 yrs
6. Vision impairment
o Strabismus, Cataracts, Ptosi

Question 8

What is the DDx of TS?

Answer 8

1. Noonan Syndrome
2. Pseudohypoparathyroidism-Albright Hereditary Osteodystrophy
3. Congenital lymphedema disorders (eg. Milroy lymphedema)

Question 9

What are the recommendations for TS?

Answer 9

1. Cardiac: Initial evaluation and then yearly ECHO
o BP checks at all visits
2. Endocrine:
o Growth Hormone to increase stature
o Estrogen replacement therapy
3. Early treatment of scoliosis
4. Annual skin exams
5. Annual thyroid fucntion
6. Monitor LH and FSH after age 10 years
7. School accommodations
8. Motherhood generally through adoption

Question 10

What are the major clinical manifestations of TS?

Answer 10

1. Small size
2. Short stature
3. Premature ovarian failure
4. Renal abnormalities
5. Heart defects: coarctation of the aorta, bicuspid aortic valve
6. Webbed neck, low hairline, and low set ears
7. Lymphedema
8. Cubitus valgus
9. Shield chest with widely spaced nipples