Infant Growth + Short Stature Flashcards
How does normal growth vary?
1) Wide variation in population
2) Wide variation in families
3) Different ethnic populations
4) Effects of deprivation - not enough food to get all nutrients for growth
- We have to distinguish normal variation in growth from pathological growth
What are the differences in normal growth between boys and girls?
- Girls overtake boys at 12 years old bc girls start puberty earlier
- Delayed puberty give boys 14cm more height than girls
What are the 3 phases of growth + what hormones/factors cause them?
1) Infancy - nutrition, insulin
2) Mid-childhood - growth hormone, thyroxine
3) Puberty - growth hormone, sex hormones (also stop growth)
When does growth hormone have no effect on growth?
Infancy - can have GH deficiency and be growing fine
What is needed for normal growth?
1) Health - is there pathology?
2) Food - is there a problem of nutrition? Are they getting enough and are they absorbing it?
3) Nurturing - are they bring abused/neglected? - children grow less
4) Hormones - at the right time and the right amounts
- Normal growth results from a complex interaction of all these factors
What is the definition of short stature?
- A standing height < 0.4th centile (< 2.5 SD below the mean)
- Child who falls outside mid-parental heigh range
How do you define decreased growth velocity?
- Growth of < 4cm/year during mid-childhood (babies 20cm/year, v fast)
- Decreased growth velocity < 25th centile for over 12 months, on growth velocity chart
What is faltering growth?
- Dropping > 2 centile lines on a growth chart over a period of 12 months
- In first 6 months this can be normal - changing centiles
What could a disproportionate appearance suggest and what would you do?
- Possible skeletal dysplasia
- Short and overweight - suggestive of endocrinopathy
- Monitor the child over a period of 6 months
How do you assess growth?
1) History
2) Anthropometry
3) Examination
4) Investigations and assessment of skeletal maturity (bone age)
5) Adult height prediction
How can a systemic condition lead to growth problems?
All energy is used to manage condition, not for growth
How does sleeping affect growth?
GH is produced at night in pulses
What maternal factors can affect growth?
Maternal health, smoking
What do you want to include in the history to find out the cause of growth problems?
- Nutrition and feeding
- Nausea/vomiting/bowel habits
- Sleeping
- Delayed development/syndrome
- PMH/systemic enquiry
- Family history
- Birth weight - IUGR, antenatal history
What are causes of short stature?
1) Familial
2) IUGR/SGA with poor catch up growth by 4 years old
3) Extreme prematurity < 28 weeks
4) Constitutional delay of growth and puberty
5) Nutritional/chronic illness
6) Chromosomal disorders/syndromes
7) Psychosocial deprivation
8) Endocrine causes
9) Disproportionate short stature/skeletal dysplasia
10) Idiopathic
How does extreme prematurity affect growth?
Approx 15% remain short during childhood and persists into adulthood
What is constitutional delay of growth and puberty?
- Healthy but just delayed
- e.g. delayed bone age e.g. 6 year old bones in 8 year old
- So will be short but continue growing after others have stopped e.g. at 18
- Usually a familial history
What chronic illnesses (affecting nutrition) can cause short stature?
- IBD
- Congenital heart malformations
- CF
- Coeliac disease
What chromosomal disorders/syndromes can cause short stature?
- PWS (Prader-Willi)
- RSS (Russell-Silver)
- TS (Turner syndrome)
- Noonan’s
- Pseudohypoparathyroidism
What are endocrine causes of short stature?
1) Hypothyroidism - metabolism slows down
2) GH deficiency (with ectopic posterior pituitary?)
3) Glucocorticoid excess
4) Laron’s syndrome - GH insensitivity
What do people with short stature due to endocrine causes look like and why?
Short and fat
- No where for weight to go if not growing e.g. GH deficiency
What do people with short stature due to chronic inflammatory diseases e.g. IBD?
Short and thin
What are the clinical features of coeliac disease?
1) Tiredness
2) Anaemia
3) Positive antibodies
4) Positive jejunal biopsy
5) Response to diet
6) Wasted bottom
7) Big tummy
8) If treat with gluten-free diet, height and weight improves and reached upper limit of mid-parental height
What measurements would you do in someone with short stature?
1) Height
2) Weight
3) Parent’s heights
4) Mid parental height range
5) ± Head circumference
6) ± Sitting height
7) ± Subischial leg length
How do you get the subischial leg length?
Subtract sitting height from standing height
What are 1st line investigations for short stature?
1) FBC (good measure of disease)
2) Ferritin
3) U&E
4) CRP/ESR
5) TFT
6) Coeliac screen
7) IGF-1
8) Bone age
9) CGH array/karyotype
Why do you do a CGH array/karyotype when investigating short stature?
To check for Turner’s syndrome
What are 2nd line investigations for short stature?
1) GH provocation test ± additional pituitary function tests
2) MRI brain (pituitary)
3) Skeletal survey
What is a GH provocation test?
Make them produce GH, stress hormone, created bodily stress
Why would you do an MRI of the brain?
To check if there is a tumour esp. on pituitary gland
When else can a skeletal survey show?
Any safeguarding issues
How do you investigate for bone age?
- Do an X ray of e.g. hand
- Compare each bone with atlas of reference bone for age
- Mainly phalanges
How do you treat short stature?
- Depends on the underlying cause
- GH will make most people grow
What is treatment with GH licensed for?
1) GH deficiency
2) Turner’s syndrome
3) Prader Willi syndrome
4) SGA + poor catch up
5) Chronic renal failure
6) SHOX deficiency - also seen in Turner’s syndrome
