Growth Disorders

Question 1

___ and ___ stimulates proliferation, differentiation, and metabolism of target tissue such as bone and muscle

Answer 1

igf1 and igfbp

Question 2

most specific effect of gh

Answer 2

stimulation of linear growth by action on epiphyseal cartilage or growth plates on long bones

Question 3

gh stimulants

Answer 3

deep sleep
fasting
sex steroids
stress
hypoglycemia

Question 4

gh inhibitors

Answer 4

obesity
glucocorticoids
high ffa
hypergly
hypothyroid
igf1

Question 5

mid parental height for males

Answer 5

((mother’s height + 13 cm + father’s height) +/- 5 cm)/2

Question 6

mid parental height for females

Answer 6

((father’s height - 13 cm + mother’s height) +/- 5 cm)/2

Question 7

factors affecting growth

Answer 7

genetics
chromocomsal defects
environmental
hormonal

Question 8

parameters of growth and development

Answer 8

height/length, weight, bone maturation (left wrist), dental development, presence or absence of secondary sex characteristics

Question 9

when do you consider a child short?

Answer 9

height 2 sd below mean for age

height below 3rd percentile for age

Question 10

what is growth velocity

Answer 10

change in height measured on 2 separate occasions relative to the time that lapsed between 2 measurements (at least 3 mos)

Question 11

formula for growth velocity

Answer 11

(height in cm at time 2 - height at time 1) / (months between 1 and 2 x 12)

Question 12

growth velocity for age

Answer 12

1-2 mos 38
4 mos 28
1 year 12
2 years 10
3-4 years 7
5-6 years 6
7-puberty 5

Question 13

normal physiologic variants for short stature

Answer 13

constitutional growth delay

familial short stature

Question 14

most common cause of short stature and sexual infantilism

Answer 14

constitutional growth delay

Question 15

definition of constitutional growth delay

Answer 15

deceleration of growth during the first 2 years of life

Question 16

treatment for constitutional growth delay

Answer 16

testosterone for 4-6 mos to induce puberty

Question 17

characteristics of familial short stature

Answer 17

(+) family history, normal puberty
growth is below normal curve but parallel to normal channel
no catch up growth
bone age = chronological age

Question 18

characteristics of constitutional growth delay

Answer 18

(+) family history of delayed growth and puberty
(+) with deceleration of growth during the first 2 years
catch-up growth
bone age < chronological age

Question 19

methods to assess body proportiond

Answer 19

arm span
upper segment
lower segment

Question 20

normal body proportions

Answer 20

birth 1.7
7 yo 1.3
10 yo 1.0

Question 21

proportionate, pre-natal onset type of short statures

Answer 21

iugr
down syndrome
turner syndrome
prader-willi syndrome

Question 22

what is iugr

Answer 22

birth weight and length >2 sd below the mean

due to maternal infection, hpn, smoking, alcohol, or drugs

Question 23

features of turner syndrome

Answer 23

all or part of one chromosome x is absent

low hairline, shield shape thorax, widely spaced nipples, poor breast development, no menses

Question 24

features of prader willi syndrome

Answer 24

hypotonia, obesity, hyperphagia, hypogonadism, growth failure

Question 25

proportionate, post-natal onset type of short statures

Answer 25

``` pituitary deficiency / dawrfism gh deficiency or insensitivity hypothyroid hypopituitary cushing rickets, pseudohypopth precocious puberty ```

Question 26

early cues for gh deficiency or insensitivity

Answer 26

hypogly micropenis cranio-facial midline defects growth retardation appearing before 2 years traumatic delivery exposure to cranial irradiation/trauma/infection

Question 27

how does hypothyroid cause growth failure

Answer 27

it has a direct effect on epiphyseal cartilage and permissive effect on gh secretion

Question 28

how does cushings affect stature

Answer 28

there is a direct effect of steroids in the epiphysis

Question 29

disporportionate short statures

Answer 29

skeletal dysplasias rickets untreated hypothyroid

Question 30

pertinent lab work up for growth disorders

Answer 30

``` initial: cbc, urinalysis, electrolyes, thyroid function bone age (left hand & wrist xray) ```

Question 31

specific tests for growth disorder

Answer 31

``` igf1, igfbp3 gh stimulation karyotyping (turner's) 24h urinary cortisol (cushings) cranial mri/ct (pituitary) ```

Question 32

indications for biosynthetic gh

Answer 32

``` gh deficiency turner syndrome chronic renal failure prader-willi syndrome small for gestational age ```

Question 33

duration of biosynthetic gh

Answer 33

theoretically until epiphysis is open ``` girls = 14 yo boys = 16 yo ```

Question 34

who to evaluate for growth disorders

Answer 34

height below 3rd percetile or 2 sds below mean for age downward crossing of percentile channels on growth chart slow growth velocity height below genetic potential presence of obesity, dysmorphic features, etc absence of fam his of short stature