ICR-Pediatric Growth Disorders

Question 1

Greatest determinate of size during intrauterine life. What are the big growth factors during this time?

Answer 1

Maternal-placental-fetal unit. IGF1 & IFG2 are the major growth factors.

Question 2

Causes of intrauterine growth restriction

Answer 2

Abnormal placenta, crowding, infection, toxins and chromosomal abnormality

Question 3

When do you know that intrauterine growth restriction will affect a baby’s adult height?

Answer 3

If you don’t see catch up growth in the first year of life.

Question 4

Average growth rate during intrauterine life

Answer 4

26 inches per year

Question 5

Average growth rate during infancy

Answer 5

6-12 inches per year

Question 6

How common is rechanneling?

Answer 6

Maternal factors lessen over 12-18 months and channeling can be normal during this time. This is not normal after 3 years of age.

Question 7

Average growth rate during childhood? Major growth factors during this period?

Answer 7

2-3 inches per year. GH and thyroid hormone are critical during this period.

Question 8

How does obesity contribute to length growth?

Answer 8

You get linear growth. However, obese kids are not taller because they tend to advance their growth plates as well.

Question 9

How does hypercortisolism contribute to growth?

Answer 9

You see rapid weight gain with tapering of height

Question 10

Average onset age for puberty in girls

Answer 10

8-13. Breast development is first evident. Peak heigh velocity at Tanner 2-3.

Question 11

Average onset age for puberty in boys

Answer 11

9-14. Testicular volume increase is first evident. Peak height velocity at Tanner 4-5.

Question 12

Tanner staging

Answer 12

*

Question 13

Major growth factor in puberty

Answer 13

Sex steroids

Question 14

What bones begin growing 1st in puberty?

Answer 14

Distal (feet and hands) get big 1st.

Question 15

Weight 2 standard deviations below the mean for age

Answer 15

Failure to thrive. You can also consider genetic potential and crossing lines.

Question 16

Height 2 standard deviations below the mean for age

Answer 16

Short stature. You can also consider genetic potential and crossing lines.

Question 17

Mid-parental height prediction

Answer 17

This is about 75% accurate. The further apart the parents are in height, the less accurate the test is.

Question 18

Medications that affect childhood growth

Answer 18

Glucocorticoids (autoimmune or asthma) or stimulants (ADHD suppresses appetite).

Question 19

How might mid-line defects affect stature?

Answer 19

Pituitary is also midline and TSH or GH deficiency may cause short stature.

Question 20

Screening labs you might use for growth disorders

Answer 20

CBC, ESR, serum electrolytes, LFT’s, urinalysis, thyroid function (TSH, fT4) and bone age (compare growth plates to give picture of skeletal maturity)

Question 21

Secondary labs to do for assessing growth disorders

Answer 21

Karyotype (45X), IGF-1 (GH surrogate measurement), other pituitary hormones (GnRH, Estradiol, testosterone, cortisol), celiac panel, Cl- sweat test and MRI of brain and sella.

Question 22

What will the bone age be in kids with constitutional delay of puberty (late bloomers)?

Answer 22

Bone age is delayed. They hit puberty later so they have more room in their growth plates when everyone else is growing and growth plates are reducing.

Question 23

Important factors in determining constitutional delay of puberty?

Answer 23

Late maternal menarche or paternal height growth after high school. Also confirm that there is absence of chronic disease.

Question 24

What will the bone age be in kids with genetic short stature?

Answer 24

Bone age = chronological age. There is no delay in puberty and they have a normal growth rate and velocity, they may have just started at a lower percentile due to genetics.

Question 25

What is causing this growth failure?

Answer 25

Loss of height w/gain in weight = endocrine.

Question 26

What is causing this growth failure?

Answer 26

He’s already small, but crosses weight and height lines at puberty = nutrition or GI

Question 27

What is the most sensitive predictor of health in kids?

Answer 27

Growth