Growth in Childhood

Question 1

what is documented in the “Red Book” (UK)?

Answer 1

documentation of child growth parameters

• Height
• weight
• head circumference (brain development)
• BMI
• leg length

Question 2

what is (poor) growth in infancy associated with?

Answer 2

as its an indicator of health

associated with increased morbidity and mortality

Question 3

what are centile charts used for?

Answer 3

for cumulative height – the total of all the growth they have done up until now

Question 4

what is height/growth velocity?

Answer 4

how fast a child is growing in cm/year
(many short children grow at a normal speed)

–>height now-height last time
divided by age now-age last time

Question 5

what are the influences on normal growth?

Answer 5

o Events before birth
– i.e. poor foetal growth, LBW, etc.
o Medical issues in childhood – i.e. malnutrition, chronic disease.
o Genetic factors.
o Randomness
– presence of multiple genes and the environment.

Question 6

when is the fastest phase of growth?

Answer 6

0-2 years

the child falls into their centile by age 2

Question 7

when does growth stop?

Answer 7

when the epiphyses fuse at the end of puberty

Question 8

what is the impact on height on those who start puberty late?

Answer 8

fall behind in height development

Question 9

what is growth velocity at infancy? what is this dependent on?

Answer 9

23-25 cm per year

nutrition dependent

Question 10

when does GH become the dominant driving force of growth?

Answer 10

9-12 months

Question 11

what is the most important growth factor? what is it stimulated by?

Answer 11

growth hormone (GH) 
GHRH (pulsatile release mainly overnight)

Question 12

what inhibits GH?

Answer 12

somatostatin

Question 13

what is the effect of GH that directly influences growth?

Answer 13

IGF1 production

Question 14

where is IGF1 produced?

Answer 14

in the liver and epiphyseal plates

Question 15

what may cause short stature?

Answer 15

o Poor nutrition.
o Chronic paediatric disease e.g. asthma, sickle cell, IBD
o Endocrine causes
– GH deficiency, TSH/T4 deficiency.
o Genetic disorders affecting bone growth
– achondroplasia, Turner’s & Down’s syndrome.
o Psychological distress and neglect.

Question 16

how do chronic paed diseases cause small stature?

Answer 16

inflammatory disease causes the formation of mediators that block the intracellular signals that lead to the formation of IGF1

Question 17

how does IGF1 cause growth of the skeleton?

Answer 17

osteoblasts at the epiphyses are stimulated to cause bone growth

Question 18

what causes tall stature?

Answer 18

o Syndromes of overgrowth
– e.g. Marfan’s syndrome, Soto syndrome.
o GH excess from pituitary tumour.
o Precocious puberty
– early puberty but they can also be short as adults as puberty stops earlier.
normal factors:
- tall parents

Question 19

what are causes of short stature despite having normal hormones?

Answer 19

• Turners (XO)
• Downs (T21)
• skeletel dysplasia
• significant illness
• inflammation
• poor nutrition
• burns
• achondroplasia (short sub-ischial length)

Question 20

what is the midparental centile?

Answer 20

the average adult height centile to be expected for all children of these parents. It incorporates a regression adjustment to allow for the tendency of very tall and short parents to have children with less extreme heights.

Question 21

what investigations can be done to investigate short stature?

Answer 21

• CRP
• serum Fe
• LFTs, kidney function
• TFTs
• coeliac screen (absorption issues)
• IGF1 levels
• bone age (maturity)
• MRI of pituitary

Question 22

what are the parameters for being overweight and obese for adults? how does this compare for children?

Answer 22

BMI >25kg/m2 overweight, BMI >30kg/m2 is obese.

in an adult BMI of 20 would be very good, but in a child that would be considered obese. BMI changes with age and its lower than that of adults

Question 23

what is a big complication of obesity?

Answer 23

T2DM and therefore CVD

Question 24

what is the Barker Hypothesis?

Answer 24

adverse nutrition in early life, including prenatally as measured by birth weight, increased susceptibility to the metabolic syndrome which includes obesity, diabetes, insulin insensitivity, hypertension, and hyperlipidemia

birth weight link to risk of death due to metabolic disease

Question 25

how does the age of T2DM diagnosis affect prognosis?

Answer 25

the earlier the age of diagnosis, the more aggressive the microvascular complications and the prognosis is worse

Question 26

why do people become obese?

Answer 26

• intake>expenditure
• polygenetic inheritance (monogenic obesity is rare)
• leptin deficiency (rare)
• leptin receptor deficiency (rare)
• POMC def (MSH also affected)
• MC4R def