growth in childhood Flashcards
why do we measure growth
poor growth is associated with high childhood morbidity and mortality
best indicator of ehalth
demonstration of normality of growth by age and stage of puberty
identify disorders of growth
assess obesity
how do you measure height *
when child ois lying down - legs straight head and feet flat against a board
or stood up
what is a centile chart *
a way of expressing variation within a population
they are cumulative
based on surveyrs of large numbers of children - use UK based and those from WHO that look at international population
age on x axis, height on y
growth measurements that are taken *
HC
weight
height/length
leg length
BMI
growth velocity
specialist charts
statistical distribution of height *
normally distributed
can have short and tall normals
people have to grow along a centile
why do we measure head circumference
children’s heads have fontenelles so head growth reflects brain growth
if head not growing = brain not growing
if sudden growth suggest hydrocephaly/bleed
when skull fuses dont measure head circumference anymore
describe height velocity chart *
expressed in cm/year
slow down at birth (very fast in utero)
increase in puberty because of GH and sex steroids
describe the hormonal control of growth *
GH-IGF-1 axis is the regulator of human linear growth
GH is a single chain polypeptide produced bvy somatotrophs in anterior pit - pulsitile secretion
cause production of IGF1 at growth plates and liver
IGF1 is what causes you to grow
what effects the production of GH *
nutrition
sleep
exercise
stress
describe the GH-IGF1 axis *
GRHR and somatostatin released from hypothalamus
act on the pituitary - GH released from ant pit and is bound to GH binding protein
GH act on GH receptor = GH action = IGF1 production
IGF is bound to IGF binding proteins
IGF1 acts on IGF1 receptor
growth in antenatal phase and factors that effect it *
most rapid phase
maternal health and placenta are the most important factors
growth in infancy and the factors that effect it *
rapid growth addition of 23-25cm in year 1
continuation of fetal growth
nutritionally dependant
no GH until 9-12 months
describe growth in childhood and the factors that effect it *
childhood is post-infancy to adolescence
boys born slightly bigger but growth rate in childhood is equal
GH/IGF1 axis drives growth - nutritions less important (as long as not malnurished)
describe growth in puberty *
under control of sex steroids and GH
stimulate the pubertal growth spurt
happen in early puberty in girls and late puberty in boys
describe bone age *
bones develop as cartilage then mature
IGF1 acts in the growth plates = osteoblasts get active and make bone
when stop growing, the growth plates fuse - happens at end of puberty
final part opf growth occurs to the spune and final epiphyses to fuse are in the pelvis
what do you look for when assessing someone’s growth *
are they too short or tall for age - could there be a problem
has puberty started and is it progressing normally
is growth normal for the stage of puberty
is the child overweight or obese
what can you learn by assessing growth*
centiles are not normal range - can be taller/shorter than the centile lines and still be completely normal
most children are on a centile by 2yrs and grow on same throughout childhood
patterns of growth are more important that the position on the centiles - most tall/short people are healthy and grow in a normal pattern
a child who falls significantly in a centile is not growing normally
what are the causes of short stature *
genes
pubertal growth delay - girl normally 8-13, boy 9-13.5 - if delay you dont get the normal growth spurt
IUGR/SGA - 85% people catch up to normal
dysmorphic syndromes - down’s/turner’s/skeletal dysplasias (something wrong in genes for bone)
endocrine disorders - GH deficiency/hypothyroid/steroid excess
chronoc paediatric disease - inflammation effects growth - inflammatory mediators block the intracellular signalling of GF = dont grow
psychosocial depravation - reduce GH pulsitility = reduced GH = reduced IGF1
drugs - steroids
poor nutrition
describe short stature (*
children have a normal growth pattern and mo medical problem
usually the children of short parents
not all children with IUGR catch up completely - growth will be normal in childhood but they have lost some growth in the antenatal period
what do you do if someone is below the centiles (
look at birth history and weight
parental heights
medical history
previous measurements
describe the mid-parental centile *
used to adjust the graph of centiles to the parents height
investigations if someone is dropping off the centiles (
FBC - look if infection, CRP, serum iron
liver and kidney function
thyroid func
coeliac screen
IGF 1
bone age
MRI pit
describe Turner’s *
normal intelligence
short
dont enter puberty
describe achondroplasia *
measure full height and sitting height - subtract sitting height from full to find leg length
have normal sitting weight but short leg length
describe, and list, chronic paediatric diseases *
asthma
sickle cell
juvenile chronic arthritis - inflammatory cytokines
inflam bowel disease - chron’s/coeliac
CF - not absorbing well and infection in chest
renal failure
congenital heart disease
causes of tall stature *
tall parents
early puberty - the pubertal growth spurt occurs very early However growth stops early as well so they can be short adults.
syndromes - marfans or Soto syndrome
GH excess from pit tumour - grow more before the GH haev fused
why is obesity an issue *
widespread - 2/3 adults, 1/4 of 2-10 yr olds and 1/3 of 11-15yr olds are overweight or obese
prevelence remains high
a high BMI is costly to health and social care
has wider economic and societal impacts
effect of obestity on children *
emotional and behvioural effects
subject to stigmatisation, bullying, low self-esteem
school absence
high cholesterol and BP
pre-dm
bone and joint problems
breathing difficulties
increased risk of becoming overweight adults
risk of ill health and preature mortality in adult life
complications of obesity *
T2dm - youger you are the more aggressive it is, the microvascular problems are more aggressive than in T1dm
orthopedic problems
PCOS
CVS
psychological problems
cancer
resp problems
BMI in children (
should be lower than in adults
describe the relationship between obesity and deprivation *
increased deprivation = increased obesity
probably because of diet and inability to exercise
describe syndromes leading to obesity *
short obese usually indicates a syndrome
prader-willi - cant stop themselves eating
cushings
Bardet-Biedl syndrome
describe the genetics of obesity *
polygenic inheritence
weight heritable trait - 40-70%
monogenic obesity syndromes are rare - leptin deficiency, leptin receptor deficiency, POMC deficiency, MC4R deficiency (increased muscle and fat), PC-1 deficiency
effect of weight on mortality in children *
if underweight, risk of mortality increases
if overweight - also increases
why is there an increase in obesity *
balance of food taken in and energy expenditure
hunger regulated by the hypothalamus and factors like leptin influence this
small number of people have single gene mutations that affect one of the hormones and can lead to severe obesity
In the population there are some gene variants (for example the FTO gene) which can affect eating behaviour and appetite and make an individual more likely to eat in a way that makes them gain weight.
describe how you measure children *
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.
what can effect current height position on a centile chart *
events before birth - poor fetal growth, low birth weight, prematurity
medical issues in childhood - malnutrition, chronic disease, endocrine problems
genetic - family and inherited disorders
randomness - multiple genes determine height
describe the pattern of normal growth *
fastest phase is 1st 2 yrs - children can move up and down the centiles at this phase
by 2 or 3 most will be at a centile - grow fast enough to keep on it
pubertal growth spurt - timing depends on when enter puberty
skeleton matures as child grows, the epiphyses fuse at the end of puberty and growth stops
describe the process of monitoring height growth in children *
all children should have height and weight measured occaisionally and plotted in red book
if concerned the child should be measured accurately and plotted on a centile chart for at least a year
if fast enough to stay on centile unusual to have a problem, even if short
timing of puberty effect height - those late in puberty can fall behind in height
how do we treat short stature
if growth is normal - cant do anything
if have confirmed GH deficiency - can treat
define obesity *
For adults BMI of over 25 kg/m2 is overweight and over 30 kg/m2 is obese.
Children have lower BMI than adults and this changes with age so these figures do not apply, and obesity is assessed on the BMI centile position.
describe obesity epidemiology *
rate has increased but may not go up at the same rate in the future
some nations higher rate than others - some cultures where overweight has traditionally been seen as a desirable feature indicating wealth and high status. In some areas of the world obesity is a feature of poverty and in others associated with affluence.
Some ethnic groups have less “tolerance” of obesity and are more likely to get complications like type 2 diabetes at a lower BMI
