Growth And Puberty Flashcards
What parts of life have the fasted growth
Infancy and puberty
What are the driving factors for growth at each stage of life? Infant , childhood , puberty? Key in each?
Infant - NUTRITION, good health & happiness, thyroid hormones
Childhood - GROWTH HORMONE, thyroid hormones, health & happiness, genes
Puberty - SEX HORMONES, growth hormone
Female passage of puberty? First sign onwards…
breast development
Pubic hair growth & growth spirt almost immediately after
Menarche - approx 2.5 years after start of puberty and signals end of growth (~5cm remaining)
Males passage through puberty ?
1st - testicular enlargement to >4ml
Pubic hair growth
Growth spirt (~18 months after start of puberty)
How can you measure tesicles
Orchidometer
What signs are seen in both males and females going through puberty
Acne, body odour, axillary hair, mood changes
Define short stature
Height 2SD below mean for age and sex
What’s a sensitive way to measure growth failure ?
Assessing height velocity
2 accurate measurements 6/12 - 12/12 apart allow HV to be calculated in cm/year
What cohort will have 1/3 remaining short ?
IUGR / extreme prem
Estimate genetic height target
Parents height / 2
(+7 for boys, -7 for girls)
Range - (+-10cm for boys, +-8cm for girls)
What are the causes of short stature
Familial Constitutional delay Endocrine Nutritional / chronic illness Chromosomal disorders / syndromes Disproportionate short stature
What causes constitutional delay ? What will the body type be? Other features? How can you induce puberty ?
Dieting or extreme exercise (FHx if not)
short body, long legs
Bone age will show moderate delay
Androgens
Usual Sx of endocrine causes of short stature ? Causes?
Falling off centiles, short & relatively overweight
Hypothyroidism - usually autoimmune
GH deficiency
Corticosteroid excess
Causes of GH deficiency ? What other feature?
Isolated or secondary to pan hypopituitarism (craniopharyngioma, meningitis, trauma)
Bone age markedly delayed
Usual cause of corticosteroid excess? What needs to be looked out for?
Iatrogenic
Features of cushings
Usual shape of nutritional cause of short stature? Causes?
short & underweight
Coeliac, crohns, cystic fibrosis, chronic renal failure
Chromosomal causes of short stature
Downs, tuners, noonan’s & russel-silver syndromes
What causes disproportionate short stature ? Limbs
Achrondroplasia, storage disorder
What investigations can be done for short stature and rational? Which diseases cause?
X-ray L wrist - bone age (*+++decreased in endocrine, + decreased in constitutional)
FBC - anaemia in coeliac / crohns
U&E’s - increased creatinine in renal failure
TSH- increased in hypothyroidism
CRP - increased in crohns
Antiendomysial / anti globin antibodies - coeliac
Karyotype (females) - 45X0 in turners
MRI - if neuro Sx - craniopharyngioma / Intra cranial tumour
Primary causes of tall stature ? What happens in secondary (rare) endocrine causes?
Marfan’s (fibrillin) & Klinefelter’s (XXY, small testis)
CAH & precocious puberty cause an initial growth spurt, but early epiphyseal fusion -> usually means eventual height is decreased
Define precocious puberty
How is precocious puberty categorised ?
Levels of pituitary gonadotropins
If ^ FSH & LH -> central cause
If decreased FSH & LH -> peripheral cause
Most common peripheral cause of precocious puberty ?
Adrenal (+gonadal) tumours -> excess sex steroids
When would you ?tumour in central cause of precocious puberty?
Visual disturbance, CNS abnormality, other signs of raised ICP
Management of precocious puberty
Detection and treatment of any underlying pathology
GnRH analogues are treatment of choice if physiological (to prevent short stature)
What is breast development called?
Thelarche
Usual person affected by premature Thelarche ? Is it always symmetrical ?
6 months - 2 years, female
No
How do you differentiate premature Thelarche from PP?
Absence of axillary & pubic hair and no growth spurt
What needs to be done for premature breast development ?
Nothing
It is benign and self limiting
What is the growth of pubic hair called?
Arenarche
When is premature pubic hair growth?
Before 8 in girls, 9 in boys
What is the common cause of premature pubic hair growth ?
Accentuation of the normal maturation of androgen production by the adrenal glands (adrenarche)
Who commonly gets premature pubic hair growth ?
Asian and Afro Caribbean children
Management of premature pubic hair growth ?
Usually self limiting
USS ovaries & uterus, and bone age to exclude PP
When is puberty classes as delayed ? Who is it more common in?
14 in girls, 15 in boys
Boys - *constitutional delay (with FHx in father) *
Males with delayed puberty are often….?and have…?
Short during childhood
Delayed skeletal maturity on bone age
What should be done in girls with delayed puberty ?
Karyotype to identify turners (45XO)
Measure sex hormones, TSH, T3,T4
None delayed puberty causes of decreased FSH & LH
Systemic disease (CF, coeliac, crohns, anorexia nervosa, excess exercise) Isolated GNrH/GH deficiency or panhypopituitarism (?craniopharyngioma)
Causes of increase FSH & LH
Chromosomal abnormalities (Klinefelter's 47XXY, turners 45XO) Acquired gonadal damage (chemo, trauma, testicular torsion)
What can cause a disorder of sexual differentiation ? How common
Congenital adrenal hyperplasia (1:5000)
What makes Congential adrenal hyperplasia more common?
Presents from number of autosomal recessive disorders -> if parents related = more common
What is cause in >90^ of CAH ? What is it used for? What is also a common feature?
Deficiency of 21-hydroxylase (needed for cortisol biosynthesis)
80% cannot produce aldosterone (salt losers)
What does cortisol deficiency do to a fetus?
Increased ACTH release & adrenal hyperplasia
Clinical features of CAH
Virilization of female external genitalia with clitoral hyper trophy (+- fusion of labia)
- salt losing crisis* at 1-3 weeks old in 80% of males (salt losers)
- Tall stature in remaining 20% (non salt losers) and precocious puberty*
Features of salt losing crisis
Hypotension, circulatory collapse, floppiness, vommiting & weight loss
What can aid CAH diagnosis
Markedly raised levels of metabolic precursor 17a-hydroxyprogesterone in blood
Management of CAH
Females - surgical correction of genitalia malformations
Life long glucocorticoids to suppress ACTH levels and allow normal growth
Mineralcorticoids (fludrocortisone) in salt losers
Growth monitoring
