Growth Flashcards
When, relative to menarche, does the peak growth rate for girls occur?
Prior to it… He said typically at menarche girls have about 2 inches in height left.
Formula for expected height based on parents’ heights?
Boys: [(M+F) + 5] / 2
Girls: [M+F) - 5] / 2
(I’m assuming this is in inches?)
2 non-pathological reasons a 13 year old might be shorter than expected?
Genetic short stature
Constitutional delay - i.e. “late bloomer”
Almost every chromosomal abnormality is associated with short growth, but which one do you look out for that really starts to show up around puberty?
Turner syndrome
Can psychosocial deprivation impair growth?
Yes, independently of nutrition.
3 endocrine disorders that can cause altered growth rate?
Hypothyroidism
Excessive steroids
GH deficiency
What does a delayed (overly young-looking) bone age mean, with regards to a person’s growth?
Either they’re a late bloomer, or there’s disease.
7 things to measure in blood to assess growth problem?
CBC ESR Celiac Chemistry (electrolytes, kidney/liver function) Karyotype Growth hormones (IGF-1, IGF-BP3) TSH, free T4
Review (and one new thing): How do you measure GH activity in serum?
IGF-1 and IGFBP-3
What does a GH deficiency look like?
Slow growth velocity
Delayed bone age
Low IGF-1 and IGFBP-3
Failed GH provocative testing (I guess this means you can’t stimulate GH release)
Are boys different from girls in utero, hormonally?
As infants?
In utero: Yes, huge hormonal differences.
In infancy: Nope, should be the same.
What’s important to know about 17-alpha-hydroxyprogesterone?
If elevated, it’s a sign of CAH (the most common form - a defect in 21 hydroxylase)
Important: Testicular enlargement before what age is abnormal?
After what age is no testicular enlargement abnormal?
Before 9 years - abnormal.
After 14 years - abnormal.
Important: Breast development before what age is abnormal?
After what age is no breast development abnormal?
Before 8 years - abnormal.
After 13 years - abnormal
3 causes of central precocious puberty?
Idiopathic
CNS pathology (?)
Hamartoma
3 peripheral causes of precocious puberty?
Ovarian cysts.
McCune Albright Syndrome (Cafe-ole spots, bone cysts, precocious puberty).
Exogenous steroid exposure.
Treatment for precocious puberty?
GnRH agonists (suppresses LH and FSH)
Leuproline (Lupron)
Histrelin implant
-Most of the time, one doesn’t treat it, though.
What’s Tanner stage 1?
No development at all.
What’s Tanner stage 4 for breast development?
Areola is raised: “Mountain on mountain.”
often coincides with menarche, though the processes aren’t directly related
What’s Tanner stage 4 for pubic hair?
Hair goes up to the belly button.
Fun fact: Belly button lint is believed to be largely due to underwear lint migrating up the hair trail to the navel.
Why screen infants for hypothyroidism?
Because congenital hypothyroidism will cause severe mental retardation if untreated.
How can treatment completely prevent the negative effects of congenital hypothyroidism?
Because before birth, infant is getting thyroid hormones from mom across the placenta. If replaced starting at birth, the baby will never be deficient in them.
One anatomic anomaly that you might find in congenital hypothyroidism?
Lingual thyroid - due to the gland failing to migrate (through the foramen cecum).
