fundamentals of growth and puberty

Question 1

what are the requirements for normal human growth?

Answer 1

Absence of chronic disease, emotional stability, secure family environment, adequate nutrition, hormones/growth factors, healthy growth plates

Question 2

what is the ICP model and what dos it show?

Answer 2

ICP model – Infant Child Puberty Model

Human grows in 3 different ways depending on whether they are in infancy, childhood or puberty

Overall growth pattern is a sum of these 3 growths

Question 3

during infancy, what is the most important factor of growth?

Answer 3

nutrition

Question 4

what is the rate of growth at infancy?

Answer 4

25cm/year

Question 5

what is the most important factor of growth during childhood?

Answer 5

GH-IGF axis – pituitary makes growth hormone which leads to the production of insulin like growth factor.

Question 6

what is the rate of growth in childhood?

Answer 6

4-8cm/year

Question 7

what is the most important factor of growth during puberty?

Answer 7

sex steroids: increase in growth hormone

Question 8

what is the rate of growth during puberty?

Answer 8

12cm/year

Question 9

why do we measure growth?

Answer 9

indicator of general health and well-being

Question 10

why do we measure height and weight?

Answer 10

useful for identifying disorders affecting growth (such as Turner’s syndrome (lack an X chromosome) and growth hormone deficiency) - special growth charts for this.

More controversial; screening for tall stature – some diseases lead to tall stature and need to be screened for.

Question 11

what are the elements of a well-functioning monitoring system?

Answer 11

• Calibrated equipment
• Correct measurement technique
• Systematically collected growth data
• Appropriate, up-to-date growth reference
• Screening rules for abnormal growth
• Referral criteria
• Adherence to guidelines
• Appropriate diagnostic work-up

Question 12

how should babies be weighed?

Answer 12

without any clothes or nappy

Question 13

how should children older than 2 years be weighed?

Answer 13

in vest and pants but no shoes or dolls/teddies in hand

Question 14

how should children over 2’s length be measured?

Answer 14

use proper equipment; length board or mat. No nappy or footwear

Question 15

when should length be measured?

Answer 15

after 2 years of age

Question 16

how should you measure the length of a child under the age of 2?

Answer 16

board or mat – requires 2 measurers. 1 measurer holds head of child, and the other adjusts the sliding board to see where the legs end

Question 17

what equipment do you use to measure height?

Answer 17

rigid ruler or stadiometer

Question 18

how should height be measured?

Answer 18

o Ensure heels, bottom, back and head are touching the apparatus
o Measurer holds child over the mastoid processes to ensure contact is maintained with the stadiometer
o Don’t try to stretch up, measure on expiration
o No footwear

Question 19

what are centiles?

Answer 19

describes the % of people below that line

Question 20

why are there no centile lines between 0 and 2 weeks?

Answer 20

because some degree of weight loss is common after birth for healthy term infants. Birth weight gained back after 2nd week.

Question 21

in what cases do children need further assessment of growth?

Answer 21

• Where weight or height or BMI is below the 0.4th centile, unless already fully investigated
• If the height centile is more than 3 centile spaces below the mid-parental centile.
• A drop-in height centile, position of more than 2 centile spaces (exclusion of measurement error).

Question 22

how will advanced bone age present?

Answer 22

often tall stature and may have central precocious puberty (too soon).

Question 23

how does delayed bone age present?

Answer 23

growth failure secondary to paediatric Cushing’s disease

Question 24

define short stature

Answer 24

Defined as a length or height less than - 2SDS (mean height standard deviation score) = 2.3 centile for age and sex of appropriate reference population

Question 25

how can you evaluate short stature?

Answer 25

• height vs centile weight - failure to thrive or grow
• when it starts
• body proportions - primary or secondary growth disorder
• presenting signs

Question 26

what are the types of short stature?

Answer 26

proportionate

disproportionate

Question 27

if it’s disproportionate short stature then what can it be?

Answer 27

skeletal dysplasia

severe case of rickets

Question 28

if it’s proportionate short stature, then what tests do you carry out and what do these show?

Answer 28

psychosocial assessment - psychosocial growth retardation

syndromic features karyotype (girls) - Turner Syndrome

tests for systemic disorders - chronic renal insufficiency, GI disease, nutritional disease

tests for endocrine disorders - hypothyroidism, hypercortisolism

Question 29

what is linear growth a combination of?

Answer 29

• Detaled auxological assessment
• Bone age assessment
• Estimate height velocity (cm/year)
• Signs and symptoms of underlying case
• Assess pubertal status
• Consider genetic growth potential from parental heights

Question 30

what does the HPG axis initiate?

Answer 30

growth and maturation

Question 31

when does puberty occur?

Answer 31

when GnRH secretion and HPG axis are re-activated (caused by pulsatile GnRH release from hypothalamus)

Question 32

when are the first physical markers of the onset of puberty in boys and girls?

Answer 32

• In girls 8-13 years

* In boys 9.5-14 years.

Question 33

which gender has a taller prepubertal height?

Answer 33

males

Question 34

what is the difference in adult height between males and females?

Answer 34

13cm

Question 35

What is Puberty Staging by Tanner?

Answer 35

method of assessing the pubertal staging of boys and girls

Question 36

explain the puberty staging by tanner in girls

Answer 36

In girls we look at the axillary hair, pubic hair and breasts. (APB)

Question 37

explain the puberty staging by tanner in boys

Answer 37

we look at axillary hair, pubic hair and testes (genitals) – APG

Question 38

what is the prepubertal staging in boys and girls?

Answer 38

A1B1P1 for girls and A1P1G1 for boys. As soon as its 2, its onset of puberty.

Question 39

what is the onset of puberty defined as in terms of Tanner staging?

Answer 39

• Tanner stage B2 for girls (budding of the breast)

* Tanner Stage G2 = Testis volume > 3mL in boys

Question 40

when is the mean onset of puberty for boys and girls?

Answer 40

11yrs for girls

12 yrs for boys

Question 41

what is the range of ages for when puberty can starts in boys and girls?

Answer 41

boys - 9 and 15

girls - 8 and 15

Question 42

what is the difference in adult height between men and women and why is this?

Answer 42

• 2 additional years of prepubertal growth in boys
• Taller prepubertal height in males
• Greater amplitude of the spurt in males

Question 43

why does earlier onset of puberty mean you grow less?

Answer 43

bc your body is exposed to higher amounts of oestrogen and progesterone which fuses growth plates

Question 44

what conditions can early onset of puberty lead to?

Answer 44

breast cancer, endometrial cancer, type 2 diabetes, hypertension, obesity, adolescent risk behaviour, adult height and psychosexual development

Question 45

what conditions can late onset of puberty lead to?

Answer 45

cognitive and learning disabilities, self esteem, adult height, osteoperosis, psychosexual development