Normal & Abnormal Growth

Question 1

What are the three phases of growth and the main factor influencing each phase?

Answer 1

1. Infant - nutrient led
2. Child - GH hormone led
3. Pubertal - Steroid hormone lead

Question 2

When is length measured and when is height measured?

Answer 2

Length used for children <2 years

Height used for children >2 years

Question 3

What triggers the onset of puberty?

Answer 3

Release of GnRH from the hypothalamus

Question 4

What influence does leptin have on the start age of puberty?

Answer 4

Start age of puberty is lowered. Those who are overweight have more leptin due to more fat. Leptin increases release of gonadotrophins.

Question 5

What is the Tanner staging a marker of?

Answer 5

Marker of sexual maturity

Question 6

According to Tanner staging - when is the onset of puberty in boys?

Answer 6

When testicular volume >4ml

Question 7

According to Tanner staging - when is the onset of puberty in girls?

Answer 7

When Tanner stage 2 has been reached

Question 8

Height difference between males and females is a result of what?

Answer 8

• Greater peak height velocity (PHV) in males
• Delayed PHV in boys
• Greater pre-pubertal height in males compared to females

Question 9

What are some causes of short stature?

Answer 9

1. Genetic
2. Endocrine
3. Chronic Disease
4. Constitutional growth delay
5. Dysmorphic syndrome
6. Psychosocial deprivation