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Video

  • Height: feet back against the wall, stand straight forward, look forward, use piece of cardboard to measure the height of the child
    • Make sure shoes are off, feet flat on ground, heels against the wall, use something flat to measure the level of the top of the head against ruler
  • Head circumference - measure 3 times to get a consistent reading. Measure from the most prominent part of the forehead to the most prominent part of the occiput to get the largest diameter
  • Measure weight
  • Plot these values on a growth chart compared to his age and work out which percentile he sits in. Make sure to get the correct chart (for the correct age)
  • Head circumference percentile can be quite different to both height and weight. Need to look at it over time to see the trend of growth - the growth series allows us to assess whether there are any abnormalities in child brain/head growth

Measurements in the group

  1. Why might there be differences amongst the group in these growth parameters?
    • Genetic and possibly nutritional differences
  2. How accurate do you think these measurements are?
    • Height wasn't accurate - tape not long enough
    • Incorrect measuring and measurement error
  3. What can interfere with accuracy of growth measurement?
    • Clothing, equipment, posture of child, poor plotting, etc etc
  4. Why is it important that these measurements are accurate?
    • Reduces the chance of false alarm (e.g. different measuring technique)

Max's growth charts

  1. Should we be concerned about Max's growth?
    • No - it is normal - there are plateaus and times of increase growth but overall he is following the expected growth curves at around the 50th centile for weight and height
  2. Where does the information in the growth charts come from?
    • Cross-sectional studies of large numbers of children at all the different ages
  3. What do the percentile curves represent?
    • Percentiles rank the position of an individual by indicating what percentage of the reference population the individual would equal or exceed
  4. What range is considered "normal" for growth measurements using these charts?
  5. What is 'normal'?
    • Answers:

See picture:

Discussion of normal growth

  • How did you get on with the measuring?
  • What surprised you about this?
  • What was difficult?
    • The tape wasn't long enough
    • Judging the longest part of the head (see the notes - there is a guideline for where to put the measuring tape)
  • What was easy?
  • How would you adapt this for a child?
    • Ask them to stay still
    • Baby - take off the nappy and clothing
    • For adults, clothing is not an issue unless wearing a heavy jacket
    • If unable to stand, measure length rather than height
      • Legs straight, feet flat, lying on a flat surface

Quiz on normal growth

  1. What is the average birth weight and length in Australia?
    • 3.4 kg and 51 cm
  2. How does the rate of growth change over childhood?
    • First few weeks: beginning they lose 5-10% of body weight due to water and need to figure out how to eat outside the womb
    • First few months: double weight at four months (rapid growth)
    • 6 months - 12 months: treble their birth weight
    • 1-2 years: reach 1/5 of adult weight; 1/2 of adult height
    • >2 years: slow down
      • Newborns lose 5-10% of body weight, mostly water
      • Periods of rapid growth in infancy and late puberty e.g. doubling weight by 4th month and tripling by end of first year, pubertal rate - adolescents always hungry.
      • Growth in second year is slower - 1/2 as fast as first year
      • Growth rate declines over first years of life to become linear from 3 years to puberty (5cm/year)
  3. What is the order of growth of the body compartments (fat, bone, muscle)?
    • Body weight gain in first few months is fat (for insulation and warmth). Mainly brown fat. After 8 months is mostly bone, muscle and body organs
  4. What are the changes in body proportions during childhood?
    • 2 month foetus
      • half its height is its head
      • about 1/4 of height is below the umbilicus
    • Newborn: 45% of length is below the umbilicus, 1/4 of total body length is head
    • Adult: 60% of length is below the umbilicus
  5. Can you predict a child's ultimate height and trajectory of growth from their parents' growth?
    • Sex adjusted mid-parental heigh (target height) = the mean of parents' height and add 6.5 cm (boys) or subtract 6.5 cm (girls). Add plus or minus 10cm = the range that you might expect 95% of children with these specific data to grow to (or +/- 5 cm = 68% cm confidence interval). Note - this is only a prediction
    • Predicting growth trajectory: Age of puberty onset is inherited in some families and so can advance or delay that key pubertal growth spurt
  6. What are the main factors that facilitate normal growth in children?
    • Multifactorial:
    • Adequate nutrition
      • Differences in nutrition rather than genetics are the main reason for differences in growth between developed/developing countries. Within developed countries the variation seen in heights is mainly due to genetics as nutrition is usually good
    • Hormones and growth factors
    • Genetics
    • Emotional stimulation
  7. What are some of the causes of growth failure in children?
    • Multifactorial
    • Familial
    • Constitution (unknown)
    • Malnutrition
    • Injury, repeated/chronic disease
    • Psychosocial
    • Endocrine
    • Chromosomal

Growth variation with body type

Rate of growth

  • Years 0-1
    • 3.2kg–10kg
    • 51cm–75cm
  • Years 1-2
    • 10 kg–13kg (1/5 adult)
    • 75–81-91cm (1/2 adult)
  • 2-3 – slow down
  • 3 onwards – linear growth
  • Puberty – growth spurt

Proportions

  • Head
    • Newborn:1/4 length
    • 1year: 1/5 length
    • Adult: 1/8
  • Legs
    • Newborn:1/4
    • Adult:1/2

Ultimate height and growth

  • Can be estimated using parents – genetic potential
    • Height:
      • Average +/- 6.5cm (m/f), gives rough range +/-10cm
    • Growth:
      • Onset of puberty is often similar to parents
      • Adopted children often have precocious puberty

Factors facilitating normal growth

  • Nutrition
    • Developed countries have better nutrition and thus genetics is the key factor
    • Developing countries may have malnutrition and thus nutrition determines growth
  • Healthcare – preventing/treating illnesses
  • Economic status
  • Psychological factors – stress can affect hormones
  • Pregnancy factors – eg: smoking
  • Hormones: the right hormones at the right levels
    • GH, GHRH, T4, E and T, IGF-1, Ghrelin

Growth failure

  • Genetic abnormalities
  • Malnutrition
  • Hormonal
  • Chronic illness
  • Genetic short stature

Measurements

  • Height, weight and head circumference
    • Head circumference is an indicator of brain growth
    • Height has variations in the class due to genetics because we're in a developed country
  • Measurement accuracy
    • Height
      • Time of day – gravity compresses disks
      • Hair
      • Straight ruler
      • Parallax
      • Posture
    • Head circumference
      • Hair
    • Weight
      • Urine, daily variation
    • Accuracy is important because it allows us to pick up problems as compared to growth charts
    • The most common error is human error

Growth charts

  • Concerns
    • Prolonged significant deviation between percentiles
      • Weight is increasing, then dropping percentiles
    • Height, weight, head circumference, BMI
    • Standardised for sex, age
  • Percentiles, normal: 2SD, 3-97%
  • Standards:
    • Weight: > 95 this overweight,<5 this underweight
    • Height:<5% is diagnosis of short stature
    • Head:<5%, >95% means there could be a developmental problem



Case studies

  • Age 8, shorter than peers, <3rd percentile
    • Examine growth history, parents height, weight, genetic diseases etc, blood tests, hormone tests
    • Family history of short people, bone age 7.5, growth history consistent, hasn’t reached puberty yet
      • Testes <4ml (after puberty 20ml)
    • Familial short stature
  • 10, active, no change in height in 1 year
    • Signs, tests normal
    • Therefore human error blamed
  • 13, adopted (higher incidence of early puberty)
    • Jump in height increase at 8, men archeat 10
      • Breast development and pubic hair Tanner 5/5 (scale used to classify pubertal development)
    • Precociouspuberty
      • Growth spurt before peers, then plateau
  • Can be treated with GnRH to delay puberty
  • 14, hardly grown in a year, 50th --> 25th --> 10th percentile
    • Late puberty father
      • Bone age maturity 10yr
    • Delayed puberty, everyone else grows, percentile drops
      • Familial, can treat with testosterone to trigger puberty if concerned
      • Final height should be unchanged
  • 14, much less than 3rd percentile
    • Arrow indicates bone age
    • No pubertal development, but LH, FSH raised
      • Low hair neck line, wide mamillary distance, high palate
    • Turner’ss yndrome45,XO
      • If no treatment, will be very short
      • Treat with estrogen can develop normally + secondary sex characteristics
    • Need specific growth charts
  • 6 yo. Slow growth 50th --> 25th percentile
    • Very active, now quiet
      • Bed looks unused
      • Increased weight in the last year
      • Painless, firm swelling in neck, raised TSH, low T3 and T4
      • Thyroid antibodies present
    • Hypothyroidism
      • Hashimoto’s disease
      • Treat with T4 thyroxine
      • Leads to normal growth and recovery

Paul

  • Paul who is 8 years old, has always been shorter than his peers. He is healthy but wants to be taller as his friends often tease him.
  • His parents ask "Can't you give him something to make him grow better?"
  • What information would allow you to better assess Paul's growth
    • Medical history
    • Diet, nutrition
    • Genetics (parents' height)
  • Family heights:
    • Mother: 166cm, Father 169 cm
    • Percentiles of the parents' heights are indicated by triangles in his graph
    • Mother's parents: 150 cm and 160 cm
    • Father's parents: 155 cm and 160 cm
    • Physical examination is normal
    • Bone age: 7.5 years
    • Testes - 2 mL (normal)
  • Diagnosis: familial short stature
    • Paul's final height will be similar to that of his relatives and there is at present no treatment available

Michael

  • Aged 10, is referred after a school check up because he has not grown at all since the last examination one year ago. Michael is a very active boy, successful in sports.
  • See picture for more on the case
  • Measurement was not correctly plotted (no history of illness)

Anna

  • See pictures
  • Menarche at 10.1 is below average (normally about 13)
  • Breast development 5/5 = normal; Pubic hair 5/5 is normal
  • Diagnosis: Early puberty (oestrogen causes growth plates to fuse)
    • It is not uncommon in girls who are adopted from developing to developed countries. It occurs earlier than it would have done in the country of origin
    • Remaining growth is only a few cm. Anna's final height will be shorter than expected before puberty.
    • Puberty may be delayed by treatment with LHRH at onset of puberty

Stephen

  • Stephen is 14.5 years old. He has come to the growth clinic because he has hardly grown during the past year. Almost all the boys in his class are now taller than he is
  • He was previously of average height in his class. He prefers to play with younger boys.
  • Stephen's father had a late puberty and grew until he was 20 years old
  • Diagnosis: Delayed puberty, probably of familial type
    • Stephen is to be regularly monitored regarding his pubertal development
    • Short term testosterone treatment to trigger puberty may be considered if psychological problems occur.
    • Final height will probably not be affected by the delay
  • Note that although the Sri Lankan girl had early puberty and this boy had late puberty, for both growth was slower

Jenny

  • Jenny (14) is referred from her GP because she is much shorter than her friends. She is a pleasant and happy girl who has always been short
  • Jenny performs noramlly in school and has several friends
  • She is performing well in school
  • See picture (LH and FSH elevated)
  • Arrow shows bone age (11 years)
  • Chromosomal analysis reveals 45 XO
  • Diagnosis: Turner's syndrome
  • Without treatment, Jenny's final height will be less than 150 cm. Treatment with growth hormone will probably increase final height.
  • Treatment with oestrogens will induce secondary sexual characteristics
  • The growth chart used here is specifically for girls with Turner's syndrome (normal height range is shaded in darker yellow)

Susan

  • Susan, 6 years old, is referred from her physician because of slow growth during the last year.
  • Susan used to be a very active girl but has now become more calm and quiet
  • Mother has noticed her bed looks unused in the morning
  • See picture
  • Hypothyroidism secondary to Hashimoto thyroiditis
    • Treatment with thyroxine will normalise the levels of T2, T4 etc

Homework