Pubertal development

Question 1

When should puberty begin in girls

Answer 1

Between 8 and 13 years old

Question 2

What are the stages of pubertal development in girls

Answer 2

1. Breast development (palpable breast bud felt first)
2. Pubic hair growth
3. Accelerated height growth/spurt (may occur immediately after breast development)
4. Menarche (11-15yo)
5. Acne, axillary hair, body odour, mood changes

Question 3

Describe the changes in height during puberty in girls

Answer 3

There is an accelerated height/growth spurt that reaches its maximum early in puberty (~12yo) before menarche commences
The onset of menarche signals that growth is coming to an end ~5cm left (~4% increase)

Question 4

What are Tanner’s 5 breast development stages

Answer 4

Stage 1 = flat
Stage 2 = buds appear, breast and nipple raised, fat forms, areola enlarges
Stage 3 = breasts grow larger (conical → rounder shape)
Stage 4 = nipple and areola raise above mound; menstruation within 2 years of this stage
Stage 5 = mature adult breast is rounded, and only nipple is raised

Question 5

How does the uterus change in morphology during puberty

Answer 5

Tubular shape → pear shape

Question 6

When should puberty begin in boys

Answer 6

Between 9 and 14 years old

Question 7

What are the stages of pubertal development in boys

Answer 7

1. Testicular growth (10-15yo)
   - Testicular volume >4ml indicates puberty
   - Measure using a orchidometer
2. Pubic hair growth
3. Enlargement of the scrotum
4. Increase in length, then breadth of the penis
5. Accelerated height growth/spurt
6. Acne, axillary hair, body odour, mood changes

Question 8

When does the accelerated height/growth spurt occur in boys

Answer 8

When the testicular volume is 12-15ml
Typically 18 months after the onset puberty
Maximum height spurt at 14 yo
Later and of greater magnitude than in girls

Question 9

What are the differences between female and male pubertal development

Answer 9

In girls the height spurt can occur immediately after onset of puberty (breast development) but in boys the height spurt is delayed and can occur 18 months after onset (testicular enlargement

Question 10

What are some pubertal changes that may occur that seem abnormal but are normal

Answer 10

gynaecomastia may develop in boys
asymmetrical breast growth may occur in girls
diffuse enlargement of the thyroid gland may be seen

Question 11

What is the most common non-iatrogenic cause of insufficient corticosteroid and mineralocorticoid secretion

Answer 11

Congenital adrenal hyperplasia

Question 12

What causes congenital adrenal hyperplasia and what can it lead to

Answer 12

Autosomal recessive disorders of adrenal steroid biosynthesis
90% due to 21-hydroxylase deficiency (Required for adrenal steroid synthesis (progesterone and 17-Hydroxyprogesterone → aldosterone and cortisol
Can also occur due to 17a-hydroxylase or 11b-hydroxylase deficiency

Insufficient aldosterone → salt-loss (High K, low Na)
ACTH overproduction → adrenal androgen overproduction

Question 13

What can 17a-hydroxylase deficiency cause

Answer 13

increased 11-deoxycorticosterone (mineralocorticoid) and decreased androgens, this can lead to Na retention and K+ excretion, thus causing hypertension

Question 14

What are the clinical features of congenital adrenal hyperplasia

Answer 14

Females: Virilisation of the external genitalia(clitoral hypertrophy, variable fusion of the labia)
Males: Enlarged penis and pigmented scrotum (much harder to see)

At 1-3 weeks: salt-losing adrenal crisis: vomiting, weight loss, hypotonia, circulatory collapse

Older children: Acne, hirsutism, accelerated growth and increased skeletal maturation (due to XS androgens)
Precocious puberty (small testes)

Question 15

What investigations should be done for congenital adrenal hyperplasia

Answer 15

Bloods
- 17a-hydroxyprogesterone (greatly elevated if 21a-H or 11b-H)
- Testosterone
- ACTH: raised
- LH/FSH: raised
- U&Es (low Na, K high)
- Glucose: hypoglycaemia
- Karyotyping

Note: massive 17a-hydroxyprogesterone is seen in all newborns

Question 16

What is the management for congenital adrenal hyperplasia

Answer 16

DSD are a medical and social emergency - pending urgent tests they should NOT name or register the birth until all tests are done (do not guess)
MDT: endocrinologist, urologist, geneticists and psychologists

Affected females (uterus and ovaries present) → corrective surgery for external genitalia within first year → definitive correction delayed until puberty

Life-long glucocorticoids (hydrocortisone) (suppresses ACTH levels → suppress testosterone → normal growth and maturation)
Mineralocorticoids (fludrocortisone) + NaCl supplementation PRN if there is a salt loss
± growth hormone
Monitor growth, skeletal maturity, plasma androgens and 17a-hydroxyprogesterone levels

Question 17

What is the management for a salt losing crisis due to congenital adrenal hyperplasia

Answer 17

IV 0.9% NaCl- 20mL/kg over the first hour then repeated as necessary
IV dextrose
IV Hydrocortisone

Question 18

What are the complications of congenital adrenal hyperplasia

Answer 18

Reduced female fertility
Short stature (premature epiphyseal closure secondary to steroid therapy
Steroid side effects
Death can occur from adrenal crisis at the time of illness or injury
Some females experience psychosexual problems which may relate to high androgen levels experienced IU prior to diagnosis
Obesity, insulin resistance and hypertension are more common

Question 19

What is the prognosis for congenital adrenal hyperplasia

Answer 19

Good if diagnosed early
Undiagnosed infants die from salt-losing crisis

Question 20

Describe 5a-reductase deficiency

Answer 20

XY genotype but cannot convert testosterone → dihydrotestosterone
→ feminisation → ambiguous genitalia with INTERNAL male organs
If left untreated, phenotypically female until puberty → increased testosterone → virilisation (‘penis at twelve’)

Can be assigned to male gender (dihydrotestosterone admin) or female (oestrogen and prophylactic orchidectomy)

Question 21

Describe androgen insensitivity syndrome

Answer 21

X-linked recessive
Resistance to testosterone → genotypically male (46XY) with female phenotype

S/S: primary amenorrhoea, groin swelling, breast development (testosterone → oestradiol)
Ix: buccal smear or chromosomal analysis

Question 22

What is the management for androgen insensitivity syndrome

Answer 22

Counselling- raise child as female?
Bilateral orchidectomy (increased risk of testicular cancer due to undescended testes)
Oestrogen therapy

Question 23

Describe complete androgen resistance

Answer 23

The external genitalia is feminised but neither the female-type nor the male-type internal tracts develop
In the absence of the androgen receptor, the Wolffian ducts will degenerate.
There is also degeneration of the Mullerian ducts due to the normal effect of testicular Mullerian regression factor