Growth And Puberty

Question 1

What parts of life have the fasted growth

Answer 1

Infancy and puberty

Question 2

What are the driving factors for growth at each stage of life? Infant , childhood , puberty? Key in each?

Answer 2

Infant - NUTRITION, good health & happiness, thyroid hormones
Childhood - GROWTH HORMONE, thyroid hormones, health & happiness, genes
Puberty - SEX HORMONES, growth hormone

Question 3

Female passage of puberty? First sign onwards…

Answer 3

breast development
Pubic hair growth & growth spirt almost immediately after
Menarche - approx 2.5 years after start of puberty and signals end of growth (~5cm remaining)

Question 4

Males passage through puberty ?

Answer 4

1st - testicular enlargement to >4ml
Pubic hair growth
Growth spirt (~18 months after start of puberty)

Question 5

How can you measure tesicles

Answer 5

Orchidometer

Question 6

What signs are seen in both males and females going through puberty

Answer 6

Acne, body odour, axillary hair, mood changes

Question 7

Define short stature

Answer 7

Height 2SD below mean for age and sex

Question 8

What’s a sensitive way to measure growth failure ?

Answer 8

Assessing height velocity

2 accurate measurements 6/12 - 12/12 apart allow HV to be calculated in cm/year

Question 9

What cohort will have 1/3 remaining short ?

Answer 9

IUGR / extreme prem

Question 10

Estimate genetic height target

Answer 10

Parents height / 2
(+7 for boys, -7 for girls)
Range - (+-10cm for boys, +-8cm for girls)

Question 11

What are the causes of short stature

Answer 11

Familial 
Constitutional delay 
Endocrine
Nutritional / chronic illness
Chromosomal disorders / syndromes 
Disproportionate short stature

Question 12

What causes constitutional delay ? What will the body type be? Other features? How can you induce puberty ?

Answer 12

Dieting or extreme exercise (FHx if not)
short body, long legs
Bone age will show moderate delay
Androgens

Question 13

Usual Sx of endocrine causes of short stature ? Causes?

Answer 13

Falling off centiles, short & relatively overweight
Hypothyroidism - usually autoimmune
GH deficiency
Corticosteroid excess

Question 14

Causes of GH deficiency ? What other feature?

Answer 14

Isolated or secondary to pan hypopituitarism (craniopharyngioma, meningitis, trauma)
Bone age markedly delayed

Question 15

Usual cause of corticosteroid excess? What needs to be looked out for?

Answer 15

Iatrogenic

Features of cushings

Question 16

Usual shape of nutritional cause of short stature? Causes?

Answer 16

short & underweight

Coeliac, crohns, cystic fibrosis, chronic renal failure

Question 17

Chromosomal causes of short stature

Answer 17

Downs, tuners, noonan’s & russel-silver syndromes

Question 18

What causes disproportionate short stature ? Limbs

Answer 18

Achrondroplasia, storage disorder

Question 19

What investigations can be done for short stature and rational? Which diseases cause?

Answer 19

X-ray L wrist - bone age (*+++decreased in endocrine, + decreased in constitutional)
FBC - anaemia in coeliac / crohns
U&E’s - increased creatinine in renal failure
TSH- increased in hypothyroidism
CRP - increased in crohns
Antiendomysial / anti globin antibodies - coeliac
Karyotype (females) - 45X0 in turners
MRI - if neuro Sx - craniopharyngioma / Intra cranial tumour

Question 20

Primary causes of tall stature ? What happens in secondary (rare) endocrine causes?

Answer 20

Marfan’s (fibrillin) & Klinefelter’s (XXY, small testis)
CAH & precocious puberty cause an initial growth spurt, but early epiphyseal fusion -> usually means eventual height is decreased

Question 21

Define precocious puberty

Question 22

How is precocious puberty categorised ?

Answer 22

Levels of pituitary gonadotropins
If ^ FSH & LH -> central cause
If decreased FSH & LH -> peripheral cause

Question 23

Most common peripheral cause of precocious puberty ?

Answer 23

Adrenal (+gonadal) tumours -> excess sex steroids

Question 24

When would you ?tumour in central cause of precocious puberty?

Answer 24

Visual disturbance, CNS abnormality, other signs of raised ICP

Question 25

Management of precocious puberty

Answer 25

Detection and treatment of any underlying pathology | GnRH analogues are treatment of choice if physiological (to prevent short stature)

Question 26

What is breast development called?

Answer 26

Thelarche

Question 27

Usual person affected by premature Thelarche ? Is it always symmetrical ?

Answer 27

6 months - 2 years, female | No

Question 28

How do you differentiate premature Thelarche from PP?

Answer 28

Absence of axillary & pubic hair and no growth spurt

Question 29

What needs to be done for premature breast development ?

Answer 29

Nothing | It is benign and self limiting

Question 30

What is the growth of pubic hair called?

Answer 30

Arenarche

Question 31

When is premature pubic hair growth?

Answer 31

Before 8 in girls, 9 in boys

Question 32

What is the common cause of premature pubic hair growth ?

Answer 32

Accentuation of the normal maturation of androgen production by the adrenal glands (adrenarche)

Question 33

Who commonly gets premature pubic hair growth ?

Answer 33

Asian and Afro Caribbean children

Question 34

Management of premature pubic hair growth ?

Answer 34

Usually self limiting | USS ovaries & uterus, and bone age to exclude PP

Question 35

When is puberty classes as delayed ? Who is it more common in?

Answer 35

14 in girls, 15 in boys | Boys - *constitutional delay (with FHx in father) *

Question 36

Males with delayed puberty are often....?and have...?

Answer 36

Short during childhood | Delayed skeletal maturity on bone age

Question 37

What should be done in girls with delayed puberty ?

Answer 37

Karyotype to identify turners (45XO) | Measure sex hormones, TSH, T3,T4

Question 38

None delayed puberty causes of decreased FSH & LH

Answer 38

``` Systemic disease (CF, coeliac, crohns, anorexia nervosa, excess exercise) Isolated GNrH/GH deficiency or panhypopituitarism (?craniopharyngioma) ```

Question 39

Causes of increase FSH & LH

Answer 39

``` Chromosomal abnormalities (Klinefelter's 47XXY, turners 45XO) Acquired gonadal damage (chemo, trauma, testicular torsion) ```

Question 40

What can cause a disorder of sexual differentiation ? How common

Answer 40

Congenital adrenal hyperplasia (1:5000)

Question 41

What makes Congential adrenal hyperplasia more common?

Answer 41

Presents from number of autosomal recessive disorders -> if parents related = more common

Question 42

What is cause in >90^ of CAH ? What is it used for? What is also a common feature?

Answer 42

Deficiency of 21-hydroxylase (needed for cortisol biosynthesis) *80% cannot produce aldosterone (salt losers)*

Question 43

What does cortisol deficiency do to a fetus?

Answer 43

Increased ACTH release & adrenal hyperplasia

Question 44

Clinical features of CAH

Answer 44

Virilization of female external genitalia with clitoral hyper trophy (+- fusion of labia) * salt losing crisis* at 1-3 weeks old in *80% of males (salt losers)* * Tall stature in remaining 20% (non salt losers) and precocious puberty*

Question 45

Features of salt losing crisis

Answer 45

Hypotension, circulatory collapse, floppiness, vommiting & weight loss

Question 46

What can aid CAH diagnosis

Answer 46

Markedly raised levels of metabolic precursor 17a-hydroxyprogesterone in blood

Question 47

Management of CAH

Answer 47

Females - surgical correction of genitalia malformations Life long glucocorticoids to suppress ACTH levels and allow normal growth Mineralcorticoids (fludrocortisone) in salt losers Growth monitoring