Growth

Question 1

size at birth is determined by which factors?

Answer 1

mum’s size
placental nutrient supply

Question 2

when does GH start becoming important for growth?

Answer 2

nutrition is main driver <3y
>3y GH deficiency only presents then

Question 3

most important determinant of growth

Answer 3

genetics - familial height, syndrome

Question 4

describe the hypothal-pit-GH axis

Answer 4

hypothal: GHRH
pituitary: GH
GH effects:
1) adipose - break down fat
2) bone, muscle etc
3) liver - break down glycogen&raquo_space; IGF-1!!

Question 5

best test for GH deficiency

Answer 5

stimulation test e.g. glucagon, arginine or insulin:
- Give glucagon
- Peak < 10 suggests severe deficiency
- 10-20 suggests mild- moderate deficiency

Question 6

in general, what stimulates GH release vs inhibit it?

Answer 6

stimulates it: things needing sugar e.g. starvation, exercise, trauma, T/E

inhibits it: don’t need sugar e.g. OBESITY, somatostatin, too much steroid

Question 7

Arm span: height should be?

Answer 7

1:1 at all ages

Question 8

height velocity - key things to note

Answer 8

• interval 1y minimum
• cannot be used over 4y
• nadir by late childhood
• pubertal growth spurt will decrease by 15-16y

Question 9

what does height age mean

Answer 9

age at which current height is 50th centile

Question 10

short stature in girls =

Answer 10

Turners until proven otherwise

Question 11

height/weight ratios at brith - what do they mean?

Answer 11

If equal reduction in parameter > TORCH/chromosomal

If height more affected > endocrinopathies/skeletal dysplasia
If weight most affected, height less and HC normal > malnutrition

Question 12

red flags for short stature

Answer 12

a. Height > 3 SD below mean > 6 cm below 3rd centile
b. Growth rate <25th percentile after 1 year of observation

Question 13

precocious puberty in boys vs girls

Answer 13

• Precocious puberty in a girl is UNLIKELY to be pathological
• Boys with precocious puberty have a brain tumour until proven otherwise

Question 14

the hormonal causes of short stature in:
1. Turners
2. renal failure

Answer 14

1. Turners = SHOX insufficiency
2. renal failure = IGF-1 deficiency

Question 15

familial short stature vs constitutional delay of growth

Answer 15

familial:
parents short
normal growth
normal puberty
BA not delayed

constitutional:
parents normal height
slow growth
delayed puberty
delayed BA

Question 16

neonatal symptoms of GH deficiency

Answer 16

hypogylcaemia, micropenis, jaundice

Question 17

most common hypothal-pit axis to be distubed by radiotherapy is?

Answer 17

GH

Question 18

GH deficiency - main causes

Answer 18

• congenital GH1 mutation
  vs
  acquired - trauma, radiotherapy, meningitis

Question 19

GH injections - start earlier or later?

Answer 19

later - speed at growing is greater, so no benefit in starting early

Question 20

exclusion criteria for GH injections

Answer 20

DM
malignancy risk or active malignancy

Question 21

AE of GH injections

Answer 21

1. risk of T2DM
2. risk of leukaemia
3. SUFE / gyanecomasia
4. hypothyroidism
   beware in OSA

Question 22

overgrowth in infancy - think of what?

Answer 22

• diabetic mum
• Sotos
• bWS