Flashcards in Growth in Childhood Deck (32)
Why do we measure growth?
Growth in childhood is the best indicator of health.
Measurement allows us to identify abnormal growth and development.
We can also assess obesity.
How do we measure length?
We measure babies flat on a measuring plate, which has 2 hard boards at either end.
Children are measured standing up with their heels against a board.
What can centile charts display?
- head circumference
- leg length
- growth velocity
Why do we measure head circumference?
When the baby is born, the skull is unfused with fontanelles. As it grows, fontanelles allow expansion of the head - if the head is not growing well, this indicates that the brain is also not growing well. We also measure to see if there is increased fluid in the head.
What is height velocity?
A measure of how quickly the child is growing - measured in cm/year.
Neonates grow very quickly, but this rate slows down over time. Mid-childhood, they grow at a rate of 5-6 cm /year.
There is a pubertal growth spurt, which can be seen on a height velocity chart.
What is the formula for height velocity?
(height now - height at last visit) / (age now - age at last visit)
Which hormone controls growth?
Growth hormone - secretion is pulsatile (influenced by nutrition, sleep, exercise and stress). It is secreted by somatotroph cells of the anterior pituitary.
GH causes cells to produce IGF-1.
Describe production and action of GH.
GHRH is produced by the hypothalamus - this stimulates GH release by somatotrophs in the adenohypophysis.
GH binds to proteins and travels to the GH receptor, initiating production of IGF-1.
Describe the action of IGF-1.
IGF-1 travels around the body bound to proteins. 70% is made in the liver.
There are IGF-1 receptors in cartilaginous growth plates of bones. IGF-1 interacts with osteoblasts in the growth plates, stimulating them to create more bone. Bones become longer and this is how we grow.
Which hormone has negative control over the growth system?
Describe the antenatal phase of growth.
Maternal health and the placenta are important factors.
IGF-2 also controls growth (paternal imprinting).
Describe the infancy phase of growth.
- rapid initial growth (23-25 cm in first year)
- decrease in velocity of foetal growth
- nutritionally dependent for first year
- GH is vital for growth from 1 year old for around 9-12 months
Describe the childhood phase of growth.
- post infancy to adolescence
- similar growth rate in boys and girls
- GH/IGF-1 axis drives growth
- less nutritional impact
Why is there a pubertal growth spurt?
Sex steroids work with GH to make adolescents grow FAST.
Eventually, sex steroids fuse growth plates and the child has reached their final height (no more growth).
Girls tend to have an earlier growth spurt. Boys tend to be around 13-14 cm taller than girls.
List some causes of short stature.
- dysmorphic syndromes
- endocrine disorders
- chronic paediatric disease
- psychosocial depravation
- normal growth pattern
What is a mid-parental centile?
A correction on growth charts to estimate the maximum potential height of the child. It shifts the normal distribution down (adjustment) for the parents' height.
List some endocrine disorders that may affect growth.
- GH deficiency
- steroid excess
List some chronic paediatric diseases that may affect growth.
- poorly controlled asthma
- sickle cell disease
- juvenile chronic arthritis
- Crohn's disease
- coeliac disease
- cystic fibrosis
- renal failure
- congenital heart disease
List some syndromes that may affect growth.
- Turner's syndrome
- Down syndrome
- skeletal dysplasias e.g. achondroplasia
List some causes of tall stature.
- early puberty
- Marfan's syndrome
- GH excess
How does obesity harm children and young people?
- stigma, bullying, low self-esteem
- high cholesterol, high BP, pre-diabetes
- bone and joint problems
- breathing difficulties
- risk of ill health and mortality in later life
List some complications of obesity.
- Type 2 diabetes
- orthopaedic problems
- cardiovascular risk
- psychological problems
- respiratory problems
How is BMI linked to deprivation?
The more deprived groups have a higher incidence of obesity.
How do genetics affect weight?
Polygenic inheritance (40-70%)
Monogenic obesity syndromes are rare:
- leptin deficiency
- leptin receptor deficiency
- POMC defciency
- PC-1 deficiency
- MC4R deficiency
What are the 4 domains of child development?
1. Gross motor skills
2. Fine motor skills
3. Speech and language skills
4. Social skills
List some common problems with or behaviours seen in children with developmental issues.
- delayed walking
- clumsy child
- delayed speech and language
- odd social interactions
- frequent night waking
What is autism?
A disorder characterised by a pattern of symptoms rather than one single symptom. These may include:
- impairments in social interaction and communication
- restricted interests
- repetitive behaviour
What is cerebral palsy?
A group of permanent movement disorders that appear in early childhood. Symptoms may include:
- poor coordination
- stiff muscles
- weak muscles
- problems with sensation, vision, hearing, swallowing and speaking
List some causes of global delay.
- chromosomal abnormalities
- metabolic disorders
- chronic illness
- antenatal and perinatal problems (illness, trauma, infections, drugs, toxins, anoxia
- environmental-social issues