Growth & Puberty Flashcards
Four phases of growth
Fetal
Infant
Child
Pubertal
Factors affecting size of fetus
Size of the mother Placentl nutrition (which modulates fetal growth factors)
Three examples of fetal growth factors
IGF2
Human placental lactogen
Insulin
What is the fastest period of growth?
Fetal
What is the effect of precocious puberty on stature?
Often shorter because earlier fusion of epiphyseal growth plates
Factors influencing infantile growth
Nutrition
Thyroid
Happiness
Factors influencing childhood growth
Thyroid
GH (IGF-1)
Happiness
Genes
Factors influencing pubertal growth
GH
Sex steroids
First sign of puberty in females. Age?
Breast enlargement (8.5-12.5 years) Growth spurt shortly after
First sign of puberty in males. Age?
Testicular enlargement (>4ml vol). 9-13 years Growth spurt 18mos after
Commonest cause of cushing syndrome in children
Excess steroids
8 causes of short stature
Familial
Constitutional delay
Severe IUGR/preterm
Endocrine (thyroid, GH, IGF1)
Nutrition/chronic illness
Psychosocial
Syndromes
Skeletal abnormalities
Commonest cause of hypothyroid causing short stature
Autoimmune thyroiditis
Features of children with endocrine caused short stature
Often weight > height centile
Features of children with short stature caused by nutrition/chronic illness
Falling off centiles
Weight < height centile
Chronic illnesses commonly causing short stature
Coeliac
IBD (Crohn’s)
CKD
Features of children with short stature due to constitutional delay
Leg growth is more mature than spine growth (pubertal growth is focused in the spine)
Causes of constitutional delay
Familial
Diet/exercise
Which syndromes can cause short stature
Turners
Noonan
Down
Russell-Silver
Investigations for short stature
Growth charts
Clinical features
Bone age
FBC (Anaemia - coeliac/crohn’s)
Bone profile
TFTs
CRP/ESR (Crohn’s, chronic illness)
GH provocation tests
IGF-1
Karyotype
Abs (coeliac)
How is bone age determined
X ray of hand and wrist
Precocious puberty girls
8 years
Precocious puberty boys
9 years
Delayed puberty girls
13 years
Delayed puberty boys
14 years
Two types of precocious puberty
Gonadotrophin dependent (central)
Gonadotrophin independent
Cause of precocious puberty in girls
Mostly familial/idiopathic
Cause of precocious puberty in boys
More likely to have organic cause
- Gonadal tumour (unilateral testis enlargement)
- Adrenal issue (bilateral small testes)
- Gonadotrophin release - from intracranial lesion (bilateral testes enlargement)
Central precocious puberty management
GnRH agonist GH therapy (GnRH agonists can stunt growth)
What should be given with GnRH agonists to avoid growth stunting?
GH therapy
Three types of delayed puberty
Constitutional
Hypogonadotrophic hypogonadism
Hypergonadotrophic hypogonadism
Is delayed puberty more common in boys or girls?
Boys
Examples of Hypogonadotrophic hypogonadism
- Diet/exercise
- Systemic disease, e.g. CF, Crohn’s, asthma
- Acquired hypothyroidism
- Hypothalamic-pituitary problems, e.g. tumours/Kallman’s
Examples of Hypergonadotrophic hypogonadism
- Turner’s
- Klinefelter’s
- Steroid hormone enzyme deficiencies
- Acquired gonadal damage
Mx delayed puberty in boys
OBSERVE
Oxandrolone - weak androgenic anabolic steroid induces catch up growth but not secondary sexual characteristics
Mx delayed puberty in females
OBSERVE
Short course oestrogen
