Growth, puberty and adolescence Flashcards
What is the middle line on a growth chart called?
Mean/median/ 50th centile
What does the standard deviation measure?
Measure of variability
What is a z score?
Number of standard deviations from the mean
If there are 100 people measured, how many are within 1 SD from the midline?
68
If there are 100 people measured, how many are within 2SD from the midline?
85
How far apart are centile lines spread?
2/3rd of a standard deviation apart
What is normal child growth?
Their measurements are within the normal range compared with children their age
Their rate of growth is within the normal range compared with children of their age
How should weight be measured in children?
Babies should be weighed without any clothes or nappies on Children older than 2 can be weighed in vest and pants, but no shoes, footwear or dolls/teddies in hand Only class 3 clinical electronic scales in metric setting should be used
How should head circumference be measured?
Head circumference should be measured using a narrow plastic or disposable paper tape
Measurement should be taken where the head circumference is widest
When should length of a child be measured?
Before 2 if concerned
Should be measured without a nappy or footwear
How should height be measured in children?
From age 2 using a rigid rule with T piece or satiometer
Ensure heels, bottom, back and head are touching the apparatus with eyes and ears at 90 degrees
Don’t try to stretch up, measure on expiration
Shoes removed
How should height be plotted on a growth chart?
Record measurement and date in ink, plot in pencil
Use dot; do not join up
Age errors are commonest source of plotting mistakes - use a calendar or date wheel to calculate age
How do you read off a growth chart?
If the point is exactly on the centile line or within 1/4 of a space, the child is described as being on the X centile
If not they should be described as being between centile C and Y
What is a centile space?
Distance between 2 centile lines
What is a centile space apart?
If two measurements are both midway between centiles
How should falls or rises be expressed?
As multiples of centile spaces e.g. a fall through 2 1/2 centile spaces
What is the average age for a girl to enter puberty?
Average age of girls entering puberty is 11 years
What are the gonadotropins?
FSH and LH
What is precocious puberty?
Puberty development occuring before 8 in girls and before 9 in boys
When is puberty delayed?
Absence of secondary sexual development in a girl aged 13 or a boy aed 14
What is the average height difference between adult males and females?
12.5 -14 cm
Boys have delayed PHV
Boys are taller pre-puberty
What does LH stimulate in boys?
The Leydig cells to produce testosterone which induces the features of secondary esexula development
What does FSH do in boys?
Binds to receptors on sertoli cells enhancing spermatogenesis
What negative feedback does testosterone have?
Inhibin B is produced by sertoli cells which exerts a negative feedback on FSH secretion
What does LH do in girls?
Stimulates proliferation of follicular and thecal cells and during the follicular phase of the menstrual cycle, induces androgen secretion by theca cells
What does FSH do in girls?
Induces proliferation of granulosa cells; increased expression of LH receptors on granulosa cells; enhances aromatase activity to produce oestrogen and increases progesterone production
What will oestrogen do to FSH cells?
Acts on FSH receptors on granulosa cells to cause proliferation of the follicular cells in addition to inducing secondary sexual development
How is puberty staged?
Tanner staging
What centiles are used in puberty?
Breast stage - thelarche is breast budding
Pubic hair stage - adrenarche is body hair and odor
Menarche - periods (usually 2 years post thelarche)
What is mid-parental height?
Plot mothers and fathers heights on respective scales and joint 2 points with a line. Mid parental centile is where this line crosses the centile line in the middle
Nine out of ten children’s height centiles are within +/-2 centile spaces of the mid parental centile line
What investigations should be performed if a growth problems is suspected?
Bloods - gonadotropins, growth factors, testosterone/oestrodiol, thyroid, karyotype
Bone age
Dynamic function tests
MRI brain, USS uterus
What is the classification of short stature?
Genetic short stature Constitutional growth delay Dysmorphic syndromes Endocrine disorders Chronic diseases Psychosocial deprivation
What is genetic short stature?
Healthy, well child who has inherited short stature from parents. No underlying endocrine abnormality and normal bone age
What is constitutional growth delay?
Late maturation causing short stature. Cause usually unknown
Tends to present around puberty with delayed onset. Children have delayed maturation and delayed bone age
