Lecture 25 - Postnatal growth

Question 1

How to measure Mid parental height

Answer 1

can be used to estiamte childs height potetnial

M + F +- 13 cm

and then + or - 8 - range

Question 2

What is Height velocity important for?

Answer 2

• important to see how fast you are growing
• lies within the 25th - 75th centile

-boys have later growth spurt than girls (due to hormones)

Question 3

What are some reasons for Short Stature

-what is HV like?

Answer 3

• short stature still can grow with normal HV
• could be due to chornic illness
• if there is a delay in growth and devleopment then could still get normal height (normal variant short stature- just haev develued in growht and devleopment)
• however if there is poor height velovity - could be pathological - could be disproportionate

Question 4

Growth hormone secretion

• when is it secreted
• what increases and decreases it
• what do you need in normal levels to get GH secretion
• what does it do?
• what inhibits IGF-1 production

Answer 4

At night
Increased by - sleep, exercise,
Decreased by - obesity

Need normal levels of insulin and normal nutrition - these are essential for normal hepatic IGF-I production

Malnutrition or poorly controlled diabetes- inhibit IGF-I production

GH promotes - endocrine, paracrine, autocrine growth

• also stimulates protein synthesis
• anti insulin - so stops glucose uptake, enhances glycogen breakdown, stimulates proteins syntehsis and lipolysis

Question 5

IGF 1

• where is it produced>
• what does it do>

Answer 5

major post natal growth promoting factor

• produced liver and bone
• insulin like = promotes glucose, lipid and amino acid uptake - cell proliferation and cell differentiation

Question 6

Estrogen

-what does it do?

Answer 6

• effects on skeleton and body comp
• has greater effect than testosterone on skeleton
• responsible for epiphyseal maturation in both sexes

Question 7

Hypothyrodisim

Answer 7

• facilitatory role in growth
• necessary for GH secretion
• necessary for growth plate development and body proportions

Question 8

Insulin

-role in growth?

Answer 8

• Facilitatory role in growth

- provides substrate for growth (amino acid uptake, glycogenesis and lipogenesis)

Question 9

Important growth promoting hormones fetus

, child

Answer 9

IGF2 , insulin

child - gh, igf1, t4/t3

Question 10

IUGR - intrauterine growth retardation or small for gestational age

Answer 10

birth weight very small

• small for gestation age
• short stature by 2 years - assocaited with shrot height
• do not reach mean pareents height

Question 11

Turner syndrome

Answer 11

• All girls with unexplained short stature or height below MPH range
• comonest feature - short for MPH
• miss an X chromosome

DOnt have normally formed ovaries
-short and late puberty