Postnatal Growth Flashcards
What are the four requirements of normal growth?
- Good general health
- Normal nutrition and genetics
- Adequate nutrition
- Caring environment
What are the three phases of growth?
- Infancy
- Childhood
- Puberty
What is the significance of GH in each of the 3 stages of growth?
- Infancy - less GH dependent
- Childhood - GH dependent
- Puberty - inc. GH release
In which growth phase is there constant annual growth?
Childhood
Humans follow a ___ gradient of growth
Cephalo-caudal
How do you calculate mid-parental height?
M (cm) + F (cm) +/- 13cm/2
A “normal” height velocity lies within the ____ centile
25th-75th
Why do boys enter into puberty later than girls?
- Oestrogen primary driver of growth
- Boys convert testosterone to oestrogen so onset is later
What are important aspects of the history of a child with short stature?
- Mother and fathers heights
- FHx delayed puberty
- Sibs child development records
What are the two growth disorders with normal height velocity?
- Familial short stature
- Constitutional delay in growth and development
How do you differentiate familial short stature from constitutional delay in growth and development?
- Delayed bone age
- Delayed puberty
Describe the secretion of growth hormone
- Pulsatile with low baseline
- Primarily at night (stages III - IV sleep)
Growth hormone stimulates the production of ___ from the liver
IGF-I
Normal levels of ___ and normal ___ are essential for hepatic IGF-1 production
Insulin
Nutrition
What is the genetic basis for Laron Dwarf?
IGF1 receptor deficiency
What is the role of oestrogen in postnatal growth?
Epiphyseal maturation/closure in both sexes
What role do T3/T4 play in postnatal growth?
- Facilitatory role in growth
- GH secretion
- Growth plate development
What are the important growth promoting hormones in the foetus?
- IGF II
- Insulin
- PDGF, EGF, FGF
What are the important growth promoting hormones in the child?
- GH
- IGF-1
- T4/T3
What are four proportionate short stature syndromes?
- IUGR
- Syndromes
- Chronic illness
- Psychosocial deprivation
What are four disproportionate short stature syndromes?
- Syndromes e.g. Turner
- Hypothyroid
- Skeletal dysplasia
Which condition should be considered in all girls with unexplained short stature or height below MPH?
Turner Syndrome
What is the commonest feature of Turner Syndrome?
Short for MPH
How do you treat Turner Syndrome?
Growth Hormone
