Child growth and Development Flashcards
Why do we measure growth?
Poor growth in infancy is associated with high childhood morbidity and mortality.
Growth is the best indicator of health – a child who is growing well will be healthy
Demonstration of normality of growth by age and stage of puberty
Measurement allows us to identify disorders of growth
Assess obesity
How is child height measured?
Babies lay on a special measuring plate. Hard board at both ends. Baby is lay flat and their length is measured.
When a child can stand up, measured upright. They need to stand up straight with their heels against a board. High accuracy
How is the accuracy of height measuring equipment ensured?
The equipment should be accurate and maintained properly
Position the child properly to get an accurate height (read the instructions on the growth chart)
Make sure you get rid of things which interfere with measuring- shoes off, hair out of the way, clothes off to weigh.
Calculate the age and plot correctly on the chart.
How are centile charts used?
Centile charts are a way of expressing variation within the population.
Head circumference Weight Height/length Leg length BMI – needs to be plotted on a growth chart Growth velocity – measured in cm/year Specialist charts
What can head circumference and Leg length indicate?
When the baby is born fontanelles present. As the brain grows, the fontanelles in the skull allow expansion of the head. If the head isn’t growing well, possible brain isn’t growing well. (Also see if there is increased fluid in the head.)
Measure leg length to detect any disproportional growth.
What do height velocity charts show?
Height velocity is expressed in cm/year
It gives people an idea of how quickly the child is growing
The baby grows very quickly in utero
When they are born, they are also growing quickly, but are slowing down
In the mid-childhood range, they are growing 5-6 cm/year
When they reach puberty, children grow VERY QUICKLY, and then stop
The pubertal growth spurt can be seen on the chart
What is GF effect on growth?
Growth hormone (GH) makes cells make IGF-1 – this is what mediates growth
The GH-IGF-1 axis is the regulator of human linear growth
GH is a single chain polypeptide – if missing need injections
Somatotroph cells of the anterior pituitary produce GH
It demonstrates pulsatile secretion, which is influenced by nutrition, sleep, exercise and stress
Negative control by somatostatin from hypothalamus
Where does IGF-1 act?
70% of IGF-1 is made in the liver. IGF-1 receptors are located within the growth plates of bones. IGF-1 has an autocrine AND paracrine effect.
The growth plate is cartilage. Within this, are osteoblasts. If IGF-1 interacts with the osteoblasts, they are STIMULATED. They begin to proliferate, and the bone becomes longer.
What are the stages of growth?
Antenatal (Fastest) - Maternal health and the placenta are important factors in control of growth. IGF-2 also controls growth (hormone that is paternally imprinted)
Infancy - Rapid initial growth (23-25cm yr1)
Continuation of foetal growth, (decreased velocity) Growth still nutritionally dependant for a year
After yr1 GH is vital in baby growth (9-12 months influence of GH) In GH deficiency, early severe plataue on growth chart
Childhood
Post infancy to adolescence. Growth rates in boys and girls similar (same growth velocity – 5-6cm/year)
GH/IGF-1 axis drives growth. Nutrition has less impact
Puberty
GH still causes growth however the sex steroids now involved. Sex steroids work with GH to increase growth velocity. Then, sex steroids fuse growth plates. Growth stops after fusion Girls tend to get their growth spurt at the beginning of puberty (slightly earlier than boys). Boys are averagely 13-14cm taller than girls
What are some causes of short height?
Genetic – short parents
Pubertal and growth delay
IUGR/SGA – 10-20% of babies who are small at birth
Dysmorphic syndromes – chromosome abnormalities often result in short stature
Endocrine disorders
Chronic paediatric disease – if you are ill, you won’t grow very well
Psychosocial depravation – stressors can affect the pulsatility of GH
Normal growth pattern
Most short children have a normal growth pattern and do not have any medical problem
They are usually the children of short parents
Not all children with intrauterine growth restriction catch up completely
Growth will be normal in childhood but they have “lost” some height in the antenatal period
What should be investigated to discover if short height is normal for a child?
Look at their birth history and weight to investigate whether there were any illnesses early on in life.
Parental heights.
Medical history of the child
Previous measurements
How is child’s potential height estimated?
MID-PARENTAL CENTILE: we can do a correction on growth charts, in order to estimate the maximum potential height of the child. It shifts the normal distribution down (adjustment) for the parents’ height.
What endocrine problems can cause short stature? What investigations could be done?
Hypothyroidism (also, thyroxine is so important for brain development)
Growth hormone deficiency
Steroid excess
Investigate - Full blood count, Liver and kidney function. Thyroid function. Coeliac screens. IGF-1 levels and bone age.
What are some non-endocrine causes of short stature?
Turner syndrome XO – females who don’t go through puberty, and are short
Down’s syndrome (trisomy 21)
Skeletal dysplasias
Significant illnesses can interfere with growth
(inflammation, poor nutrition and the effects of drugs such as steroids) This blocks the intracellular signalling processes of GH – so IGF-1 deficient
Achondroplasia - normal sitting height, abnormal standing height due to shorter legs
What are some chronic paediatric diseases?
Badly controlled asthma Sickle cell Juvenile chronic arthritis Inflammatory bowel disease (Crohn’s disease) Coeliac disease Cystic fibrosis Renal failure Congenital heart disease
