Growth And Development Flashcards
(26 cards)
During puberty, growth hormone increases, as well as…….name these growth factors and their synonym
Insulin-like growth factors one and two, or somatomedins.
How long after onset of puberty does peak height velocity normally occur?
How much later does peak height velocity occur in boys than girls.
2.5 years
Two years.
What is average peak height velocity for boys, and for girls
9 cm per year for girls, 10.3 cm per year for boys
Formula to predict mid parental height:
One. Girls
Two. Boys
Girls: (father’s height -13 cm plus mother’s height)/2
Boys: (father’s height plus mothers height +13 cm) divided by two
Name four conditions that may result in delayed bone age/maturation
Hypothyroidism, hypopituitarism, chronic illness, and constitutional delay. Turner syndrome may produce normal or delayed bone age.
Definition of precocious puberty for girls (Caucasian, African-American)
Definition of precocious puberty for boys
Girls Caucasian-less than seven years of age, African-American less than six years of age
Boys: signs of puberty at less than nine years of age
First event of puberty and girls:
Sequence of events in puberty-girls, with average length between events
Menarche usually occurs in what sexual maturity rating
Thelarche followed six months later by pubarche followed 18 months later by menarche
SMR four
Average duration of puberty-boys
Average duration of puberty-girls
Three years
Four years
What is the first event marking onset of puberty in boys?
Average age of onset of puberty in boys?
What are the next changes, marking next three stages of sexual maturity?
Testicular enlargement is the first event
Average age of onset is 11.5 years.
Stage two-testicular enlargement, slight reddening of scrotum
Stage three-penis begins to enlarge
Stage four - continued testicular enlargement, enlargement of scrotum and darkening, penis increases in length and breadth
Differential diagnosis of short stature without pubertal delay? Most common cause?
Familial Isolated growth hormone deficiency IU GR Hypothyroidism Syndromic (Down, Newnan, hurler) Skeletal disorders HIV
Describe a preliminary work up for short stature
Bone age, CBC, said rate, celiac screen, chemistry, karyotype for girls, and IGF-one, IGF BP-three growth factors, TSH, LH, FSH.
In the setting of short stature or delayed puberty, what would an elevated FSH and LH indicate?
Primary gonadal problem
Define delayed puberty for girls? Boys?
For girls, no breast development at age 13, no pubic hair after age 14, No menstruation after age 16
boys no testicular enlargement by age 14, No pubic hair after age 15
List a differential diagnosis of primary hypogonadism
Chromosomal disorders like Turner, Noonan, and Klinefelter
Incological issues
Gonadal damage
Infections like mumps
Intersex disorders like testicular feminization
With short stature, what does it mean when the weight is affected more than height?
Gastrointestinal diseases the primary consideration, as endocrine disease is unlikely. Consider also psychosocial disorders.
Work up for delayed puberty
Bone age x-ray, CBC, ESR, chemistry, IGF-one IGF-BP three, prolactin
FSH, LH, estradiol, testosterone
Low IGF-one suggests possibility of what deficiency?
Caution regarding interpretation of low IGF-I if what other finding?
Growth hormone deficiency, but caution in the setting of poor weight gain. Can be due to chronic illness such as G.I. disease
What is the mean age for onset of puberty in girls (African-American, Caucasian)?
African-American 8.9 years
Caucasian 10 years
Name tests to assess growth hormone deficiency
IGF-1 and IGF-BP-3
Glucagon stim test 1 mg results in a rise of growth hormone to greater than 7-10 ng/mL
List three criteria for short stature (in other words, when would one be concerned regarding possible short stature)
1) linear growth rate less than 4-5 cm per year before the growth spurt OR
2) height greater then two standard deviation from the mid parental height
3) height greater than three standard deviation from the mean
What is a GnRH stim test?how is it done?
What are the findings in primary gonadal failure? What are the findings in pituitary failure?
What are the findings in constitutional delay of puberty?
GnRH stimulation test determines if pituitary function is normal for degree of pubertal stage
Measure LH and FSH levels before and every 30 minutes for three hours after 100 µg GnRH
Primary gonadal failure-LH and FSH will increase normally. Pituitary failure-little increase. Constitutional delay of puberty-LH and FSH responses are small but consistent with bone age and pubertal stage
Differential diagnosis of short stature with pubertal delay. What is the most common cause?
Constitutional delay (90-95%!) Panhypopituitarism Congenital syndromes like Turner Hypogonadotrophic hypogonadism syndromes including Kallman (anosmia), PraderWlli Glucocorticoid excess Chronic illness and HIV
Differential diagnosis of excessive growth-tall stature
- Constitutional tall stature
- Excessive growth hormone
- Anabolic steroid xs (Adrenal tumor, congenital adrenal hyperplasia, precocious puberty)
- Hyperthyroidism
- Miscellaneous syndromes like Marfan, neurofibromatosis
Average age of menarche (normal range).
How long after the start of the growth spurt is menarche expected?
During what sexual maturity rating stage is menarche expected?
Average age of menarche 12 years four months (range 9-16+)
Menarche expected 3.3 years after the start of growth spurt, 1.1 years after peak height velocity
SMR three and four.
