Turner's syndrome

Question 1

What is Turner’s syndrome?

Answer 1

Nondisjunction during meiosis → complete sex chromosomal monosomy → 45 XO, no Barr body

Nondisjunction during mitosis of an embryonic cell → sex chromosomal mosaicism (45,XO/46,XX); Barr body may be present in cells with 46,XX karyotype → mild phenotype

Question 2

What are the clinical features of Turner’s syndrome?

Answer 2

Female phenotype 
Short stature/Shield chest
Webbed neck 
Gonadal dysgenesis (absence of germ cell in gonads)  
Primary amenorhea

Question 3

What are the associated complications with Turner’s syndrome?

Answer 3

Cardiovascular abnormalities: 
 Bicuspid aortic valve 
 Coarctation of aorta 
 Aortic dissection and rupture 
Kidney + Ureter malformations 
Osteoporosis

Question 4

How is Turner’s syndrome diagnosed?

Answer 4

Hypergonadotropic hypogonadism → ↓ estrogen, ↓ androgens, ↑ follicle stimulating hormone, ↑ luteinizing hormone

Question 5

How is Turner’s syndrome treated?

Answer 5

Oestrogen + Progesterone substitution