Child Growth and Development (02.03.2020)

Question 1

What is the average size of a baby born at term?

Answer 1

• 50 cm long
• 3.3 kg weight

-> growth in height is completed over the next 12-16 years

Question 2

How do you check if growth is normal?

Answer 2

centile charts

• > The pattern of growth in normal children is very consistent and centile charts are a way of checking that growth is normal
• > there is a wide range of normal heights, growth charts are good at looking at including that.
• They are based on surveys of large numbers of children- in the UK we use both UK population based charts and ones from the WHO which look at an international population.

Question 3

What factors affect growth in height?

Answer 3

• nutrition
• hormone problems
• genetic diseases.

Question 4

What specific growth measurements might you look at in children?

Answer 4

height, weight, head circumference and BMI are the commonest

Question 5

How does a gentile chart look like?

Answer 5

• you plot the age (x axis) against height (y axis).
• 50% of children will be shorter than the 50th centile
• 25% shorter than the 25th centile, and so on.
• Centile charts are not a ”normal range”, they are just a way of looking at where height is compared to others
• There are centile charts for girls and boys

The centile charts we use are for cumulative height

Question 6

Height velocity gentile charts

Answer 6

• Height velocity is how fast a child is growing in cm per year, usually this is calculated over a whole year. - Most short children are growing at a completely normal speed.

Question 7

What is some additional information when assessing a child’s height that is useful?

Answer 7

• height of family members (parents, siblings)
• ideally measure them yourself because people an be very inaccurate in assessing their own height
• mid parental height an be useful

Question 8

How do you calculate mid-parental height?

Answer 8

girls: (mom+dad)/2 -7
boys: (mom+dad)/2 +7

(this is the height expected at 18 years for the child)

Question 9

What factors influence height?

Answer 9

• Events before birth- poor fetal growth, low birth weight, prematurity
• Medical issues in childhood- malnutrition, chronic disease, endocrine problems including growth hormone deficiency
• Genetic factors- the height of the family and any inherited disorders of growth.
• Randomness. Not every child of the same parents will be the same adult height, and tall parents can occasionally have a short child. There are multiple genes which determine adult height, and these are randomly distributed at conception.

Question 10

How do children grow?

Answer 10

• The fastest phase of growth after birth is in the first 2 years of life. Children can move up and down through the centiles at this phase of growth.
• Most children will move to a centile position by 2 to 3 years of age and then continue on this centile position through childhood.
• Normal children grow fast enough to keep on the same centile and movement up or down is unusual.
• fast growth at puberty (pubertal growth spurt) - The timing of this depends on the age at which the child enters puberty.
• The skeleton matures as the child grows, the epiphyses fuse at the end of puberty, and growth stops.

Question 11

When is it normal for a child to jump centiles?

Answer 11

• The fastest phase of growth after birth is in the first 2 years of life
• Children can move up and down through the centiles at this phase of growth

Question 12

Monitoring of height growth in children

Answer 12

• All children should have height and weight measured occasionally and plotted in their red book.
• If there are concerns about growth the child should be measured accurately and plotted on a centile chart over a period of time (at least a year).
• If a child is growing fast enough to continue to grow on the same centile they are not likely to have a problem even if they are at the bottom of the centile chart.
• Timing of puberty can impact on height- children who are late in developing can fall behind in height.

Question 13

The hormonal control of growth and GH secretion

Answer 13

• GH is the most important hormonal factor in growth.
• GH secretion is controlled by the hypothalamus, which secretes GHRH which stimulates secretion and SS which suppresses secretion.
• GH is released by the pituitary as pulses most of which occur overnight.
• GH has some growth effect itself and also stimulates the release of IGF1
• IGF 1 circulates bound to a number of binding proteins and stimulates growth in all the tissues of the body

=> remembe: don’t measure GH because it is pulsatile, if you are worried about endocrine problems you must do dynamic tests.

Question 14

What is the commonest concern about growth?

Answer 14

short stature

The majority of short children have a normal growth pattern, and do not have anything wrong with them.

Question 15

What is abnormal growth?

Answer 15

• If a child grows slower than normal over a significant period of time they will fall in their centile position.
• This is abnormal and a cause should be looked for.

Question 16

Causes of abnormal growth? (short)

Answer 16

• Poor nutrition
• Chronic disease
• Endocrine causes- GH deficiency, thyroid hormone deficiency
• Genetic disorders affecting bone growth (eg achondroplasia, Turner syndrome, Down syndrome).
• Psychological distress and neglect

Question 17

Causes of abnormal growth (too tall)

Answer 17

Tall stature is a very unusual concern. Most tall children have a normal growth pattern and do not have anything wrong with them. Causes to consider are:

• Syndromes of overgrowth including Marfan syndrome and Soto syndrome
• GH excess from a pituitary tumour. This is very rare indeed, most of the “tallest men and women in the world” have had this diagnosis
• In precocious puberty the pubertal growth spurt occurs very early and so children with this can present with tall stature. However growth stops early as well so they can then be short as adults.

Question 18

GH deficiency treatment outcomes

Answer 18

Children with confirmed GH deficiency will get a significant improvement in their adult height with treatment, and there are a number of other disorders of growth where there is some benefit from treatment.

Question 19

What about changing the height of normally short children?

Answer 19

There have been multiple trials of GH treatment in children who do not have anything wrong with them but are just short (“short normal children”). Treatment is not given to these children because the tiny improvement in height seen is not worth the time, effort and expense of treatment.

Question 20

Overweight and obese definitions

Answer 20

• For adults BMI of over 25 kg/m2 is overweight and over 30 kg/m2 is obese.
• Children have lower BMI than adults and this changes with age so these figures do not apply, and obesity is assessed on the BMI centile position.

Question 21

Obesity and overweight

Answer 21

• Some ethnic groups have less “tolerance” of obesity and are more likely to get complications like type 2 diabetes at a lower BMI
• In some areas of the world obesity is a feature of poverty and in others associated with affluence.

Question 22

Complications of obesity

Answer 22

more likely to get a range of disorders including

• type 2 diabetes
• cardiovascular disease
• some cancers
• orthopaedic problems

Question 23

Genetic disorders causing ibestiy

Answer 23

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find stuff from slides

In the population there are some gene variants (for example the FTO gene) which can affect eating behaviour and appetite and make an individual more likely to eat in a way that makes them gain weight.