Growth, puberty and adolescence

Question 1

What is the middle line on a growth chart called?

Answer 1

Mean/median/ 50th centile

Question 2

What does the standard deviation measure?

Answer 2

Measure of variability

Question 3

What is a z score?

Answer 3

Number of standard deviations from the mean

Question 4

If there are 100 people measured, how many are within 1 SD from the midline?

Answer 4

68

Question 5

If there are 100 people measured, how many are within 2SD from the midline?

Answer 5

85

Question 6

How far apart are centile lines spread?

Answer 6

2/3rd of a standard deviation apart

Question 7

What is normal child growth?

Answer 7

Their measurements are within the normal range compared with children their age
Their rate of growth is within the normal range compared with children of their age

Question 8

How should weight be measured in children?

Answer 8

Babies should be weighed without any clothes or nappies on
Children older than 2 can be weighed in vest and pants, but no shoes, footwear or dolls/teddies in hand
Only class 3 clinical electronic scales in metric setting should be used

Question 9

How should head circumference be measured?

Answer 9

Head circumference should be measured using a narrow plastic or disposable paper tape
Measurement should be taken where the head circumference is widest

Question 10

When should length of a child be measured?

Answer 10

Before 2 if concerned

Should be measured without a nappy or footwear

Question 11

How should height be measured in children?

Answer 11

From age 2 using a rigid rule with T piece or satiometer
Ensure heels, bottom, back and head are touching the apparatus with eyes and ears at 90 degrees
Don’t try to stretch up, measure on expiration
Shoes removed

Question 12

How should height be plotted on a growth chart?

Answer 12

Record measurement and date in ink, plot in pencil
Use dot; do not join up
Age errors are commonest source of plotting mistakes - use a calendar or date wheel to calculate age

Question 13

How do you read off a growth chart?

Answer 13

If the point is exactly on the centile line or within 1/4 of a space, the child is described as being on the X centile
If not they should be described as being between centile C and Y

Question 14

What is a centile space?

Answer 14

Distance between 2 centile lines

Question 15

What is a centile space apart?

Answer 15

If two measurements are both midway between centiles

Question 16

How should falls or rises be expressed?

Answer 16

As multiples of centile spaces e.g. a fall through 2 1/2 centile spaces

Question 17

What is the average age for a girl to enter puberty?

Answer 17

Average age of girls entering puberty is 11 years

Question 18

What are the gonadotropins?

Answer 18

FSH and LH

Question 19

What is precocious puberty?

Answer 19

Puberty development occuring before 8 in girls and before 9 in boys

Question 20

When is puberty delayed?

Answer 20

Absence of secondary sexual development in a girl aged 13 or a boy aed 14

Question 21

What is the average height difference between adult males and females?

Answer 21

12.5 -14 cm
Boys have delayed PHV
Boys are taller pre-puberty

Question 22

What does LH stimulate in boys?

Answer 22

The Leydig cells to produce testosterone which induces the features of secondary esexula development

Question 23

What does FSH do in boys?

Answer 23

Binds to receptors on sertoli cells enhancing spermatogenesis

Question 24

What negative feedback does testosterone have?

Answer 24

Inhibin B is produced by sertoli cells which exerts a negative feedback on FSH secretion

Question 25

What does LH do in girls?

Answer 25

Stimulates proliferation of follicular and thecal cells and during the follicular phase of the menstrual cycle, induces androgen secretion by theca cells

Question 26

What does FSH do in girls?

Answer 26

Induces proliferation of granulosa cells; increased expression of LH receptors on granulosa cells; enhances aromatase activity to produce oestrogen and increases progesterone production

Question 27

What will oestrogen do to FSH cells?

Answer 27

Acts on FSH receptors on granulosa cells to cause proliferation of the follicular cells in addition to inducing secondary sexual development

Question 28

How is puberty staged?

Answer 28

Tanner staging

Question 29

What centiles are used in puberty?

Answer 29

Breast stage - thelarche is breast budding
Pubic hair stage - adrenarche is body hair and odor
Menarche - periods (usually 2 years post thelarche)

Question 30

What is mid-parental height?

Answer 30

Plot mothers and fathers heights on respective scales and joint 2 points with a line. Mid parental centile is where this line crosses the centile line in the middle
Nine out of ten children’s height centiles are within +/-2 centile spaces of the mid parental centile line

Question 31

What investigations should be performed if a growth problems is suspected?

Answer 31

Bloods - gonadotropins, growth factors, testosterone/oestrodiol, thyroid, karyotype
Bone age
Dynamic function tests
MRI brain, USS uterus

Question 32

What is the classification of short stature?

Answer 32

Genetic short stature
Constitutional growth delay
Dysmorphic syndromes
Endocrine disorders
Chronic diseases
Psychosocial deprivation

Question 33

What is genetic short stature?

Answer 33

Healthy, well child who has inherited short stature from parents. No underlying endocrine abnormality and normal bone age

Question 34

What is constitutional growth delay?

Answer 34

Late maturation causing short stature. Cause usually unknown
Tends to present around puberty with delayed onset. Children have delayed maturation and delayed bone age