Endocrinology

Question 1

What is puberty?

Answer 1

It is the stage between the onset of secondary sexual characteristics and completion of physical maturity (period in which reproductive capability is attained).

Question 2

When does puberty occur in girls vs. boys?

Answer 2

Girls = 8-13 years old 
Boys = 9-14 years old

Question 3

What is the first sign of puberty in girls vs. boys?

Answer 3

Girls: breast enlargement
Boys: testicular enlargement

Question 4

What is the sequence of puberty in girls?

Answer 4

Thelarche - adrenarche - growth spurt - menarche

Question 5

What is the puberty sequence in boys?

Answer 5

Testicular enlargement - adrenarche - spermatogenesis - growth spurt

Question 6

What is the most important factor that influences normal puberty?

Answer 6

Genetics

Question 7

What is precocious puberty?

Answer 7

In girls: onset of puberty “breast enlargement” before the age of 8 years.

In boys: onset of puberty “testicular enlargement” before the age of 9 years.

(5 times more common in girls than boys)

Question 8

What are the types of precocious puberty?

Answer 8

Central, true, GnRH-dependent:
MOST COMMON

Peripheral, pseudo, GnRH-independent:
Not a major type (outside the CNS)

Isolated forms (benign in nature):
Thelarche
Adrenarche/pubarche

Question 9

What is the most common CNS disorder that causes central precocious puberty?

Answer 9

Hypothalamic hamartoma

Question 10

What is the most common adrenal cause of peripheral precocious puberty?

Answer 10

Non-classical congenital adrenal hyperplasia (CAH) + adrenal tumors

Question 11

What are variants of normal puberty?

Answer 11

• Isolated benign thelarche

- Isolated benign adrenarche (pubarche)

Question 12

What is the onset of isolated benign thelarche?

Answer 12

Between 6 months to 4 years of age

Question 13

What are some of the investigations done in precocious puberty? (To differentiate between central and peripheral types)

Answer 13

• Basal LH, FSH and sex steroids
• GnRH stimulation test
• hCG
• Inhibin
• 17 OHP
• Adrenal androgens
• Bone age
• MRI brain
• US of testes
• Pelvic US
• Adrenal US
• Abdominal US

Question 14

What is the treatment of central precocious puberty?

Answer 14

• GnRH agonist

* Treatment of underlying pathology

Question 15

What is the treatment of peripheral precocious puberty?

Answer 15

• Medroxyprogesterone acetate (provera)
• Ketoconazole ~rarely used
• Aromatase enzyme inhibitors
• Androgen antagonists

Question 16

When is the classic onset of premature adrenarche?

Answer 16

Occurs after 5 years of age (with onset of pubic hair, axillary hair and apocrine growth)

Question 17

What is the etiology of central precocious puberty in girls vs. boys?

Answer 17

Girls: most cases are idiopathic
Boys: most cases are pathologic (all patients need evaluation with an MRI of the head)

Question 18

What is delayed puberty in girls vs. boys?

Answer 18

Girls: no breast tissue by 13 years of age, or no menarche by 16 years of age

Boys: no testicular enlargement by 14 years of age