Sexual development + disorders

Question 1

Tanner stages for pubic hair?

Answer 1

Stage 1: Pre-adolescent (prepubertal)
Stage 2: Sparse hair, long and slight pigmentation
Stage 3: hair spread over junction of pubes, darker and more coarse
Stage 4: adult type hair, but lesser distribution
Stage 5: adult in quantity and type

Question 2

First sign of pubertal development in boys?

Answer 2

Increased testicular volume

Question 3

Age of precocious puberty in girls?

Answer 3

<8 years

Question 4

Age of precocious puberty in boys?

Answer 4

<9 years

Question 5

Main cause of precocious puberty in girls?

Answer 5

~90% idiopathic

Question 6

Indications for MRI Brain in girls with precocious puberty?

Answer 6

Girls without pubic hair
Estradiol >30pmol/L
Age <6yrs

Question 7

Gonadotropin dependent causes of precocious puberty include?

Answer 7

Hamartoma
Brain tumour (glioma, germinoma)
Hypothyroid

Question 8

Gonadotropin independent causes of precocious puberty include?

Answer 8

McCune Albright Syndrome
CAH
Ovary and adrenal tumours

Question 9

Features of McCune Albright syndrome?

Answer 9

Cafe au lait (Coast of Norway)
Polyostotic fibrous dysplasia
Thyroid adenoma
Acromegaly
Cushings

GNAS mutation at Arg 201 (missence mutation of the gene for G protein)

Question 10

Normal male sex determination requires what?

Answer 10

SRY (sex determining region
Intact testis with functioning Leydig and Sertoli cells
Presence of 5-alpha reductase

Question 11

What do Leydig cells release during sexual differentiation?

Answer 11

Testosterone

Question 12

What do Sertoli cells release during sexual differentiation?

Answer 12

MIH (Mullerian inhibitory factor)

Question 13

What are the 2 top causes of indeterminate gender?

Answer 13

CAH (60%)
Gonadal dysgenesis (30%)

Question 14

If there is no uterus present with indeterminate gender what is the differential diagnosis?

Answer 14

CIAS/PIAS
5-alpha reductase deficiency
Inborn error of testosterone metabolism
17-B-HSD deficiency
(Means MIH release from male gonad)

Question 15

If there is a uterus present with indeterminate gender, what are the possible diagnoses?

Answer 15

CAH
Gonadal dysgenesis
(MIH negative)

Question 16

Causes of primary hypogonadism include? (5)

Answer 16

Galactossaemia (causes fibroid ovaries)
Hemachromatosis (iron in gonad)
Chemotherapy
Klinefelters
Turner syndrome

Question 17

Causes of secondary hypogonadism include? (3)

Answer 17

Kallman’s syndrome
Moebius anomolad
Prader-Willi syndrome

Question 18

Features of Kallman’s syndrome?

Answer 18

Hypogonadotropic hypogonadism
Anosmia
Hearing impairment

Cause: failure of migration of cells with KAL1 gene problem