Who remembered that daylight savings is this weekend?? A. I
did! B. Nooooooooo!!!
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Developmental stage characterized by: Maturation of
gametogenesis Secretion of gonadal hormones Development of
secondary sexual characteristics and reproductive functions
Pediatricians are constantly faced with questions about what is
normal during puberty Changes in GnRH secretion (increased
pulsatility) result in puberty
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Age of onset: Girls: 8-13 years Thelarche can occur at age 7 in
African-American and Mexican American girls Boys: 9-14 years Sexual
Maturity Rating (SMR) Used to document a childs development through
puberty Consists of inspection of breast, genital, and pubic hair
development Limitation: does not have specific measurements
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Stage 1: prepubertal Stage 2: girls: thelarche boys: testicular
enlargement (4mL) Stage 3: ongoing Stage 4: nearly complete Stage
5: adultlike Pubertal progression from stage 2 to stage 5 can take
between 2.5-5 years to complete
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Which is the correct sequence of pubertal events in a female?
A. Menarche thelarche peak height velocity pubarche B. Thelarche
pubarche peak height velocity menarche C. Pubarche thelarche
menarche peak height velocity D. Thelarche pubarche menarche peak
height velocity
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Males: Testicular growth pubarche penile growth peak height
velocity Testicular volume < 4mL (2.5cm) is prepubertal Reach
SMR4 prior to attainment of peak height velocity Females: Thelarche
pubarche peak height velocity menarche Peak height velocity is
typically 1 year before menarche Girls height will typically
increase ~6-8cm after menarche has occurred
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A mother brings in her 13 year old son at his request due to
his concerns about breast tissue. He has noticed he has a small
amount of breast tissue and wants to know if it can be removed. He
is otherwise developing appropriately and does well in school. On
exam, he is SMR3 for genital growth and pubic hair. You also notice
a small amount of breast tissue bilaterally under his nipples. What
is the most appropriate course of action? A. Refer the patient to a
plastic surgeon B. Refer the patient to an endocrinologist for
hormone therapy C. Order a brain MRI to rule out malignancy D.
Reassure the patient that this is a normal part of puberty and
follow up in 6 months E. Order FSH and LH levels
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Asymmetric breast or testicular development Can see up to 1
stage advance of unilateral development at onset of puberty
Gynecomastia 50% of boys will have some degree of breast tissue
during puberty Typically during pubic hair stage 3 or 4
Gynecomastia without onset of puberty is concerning Lasts less than
1 year Can just be observed for resolution
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Peak height velocity in girls occurs earlier chronologically
and in pubertal staging than in boys Boys growth spurt is typically
2 years after girls Peak height velocity is more closely correlated
with SMR than chronologic age
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Average prepubertal height velocity 5-6cm/yr Average pubertal
height velocity: Boys = 9-10cm/yr Girls = 8-9cm/yr Completion of
this growth spurt takes 2-4 years Longer period of prepubertal
growth and greater pubertal height velocity account for the typical
height discrepancy between males and females Longitudinal growth
chart is much more useful in determining abnormality of growth
versus a single point in time
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A boy comes in with his parents for his 12 year old well-child
check and wants to know how tall he is going to be. His mother
reports that he has been growing but that he is shorter than most
of his peers. His mother is 160 cm (63 in) tall and his father is
172 cm (68 in) tall. With the exception of his relative short
stature, his medical history is unremarkable. You advise him that
the best way to estimate his potential for growth is to calculate
his midparental target height and compare it to his current height
and his skeletal maturity. Of the following, what is the BEST
estimate of his midparental target height? A. 160 cm (63in) B.
165.5cm (65in) C. 172.5cm (68in) D. 177.5cm (70in) E. 182.5cm
(72in)
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Height is largely determined genetically Target height can be
crudely estimated: Average of parents heights in cm +6.5cm for boys
-6.5cm for girls Bone age can also be used predict height Best
performed by an endocrinologist Keep in mind a bone age can be off
from chronologic age by as much as 2 years and still be normal (ie
constitutional growth delay)
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There is a genetic influence on the timing of puberty
?autosomal dominant Earlier puberty: will have tall stature during
puberty compared to peers Will complete their growth prematurely
and have a lower peak adult height than expected Rapid fusion of
their growth plates Later puberty: short stature in youth but an
adult height that is slightly above expectations Slow but constant
prepubertal growth of long bones without rapid maturation of the
growth plate Timing of puberty affects both linear growth rate and
skeletal maturity
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A mother brings in her 9 year old daughter because she saw some
blood in her underwear and is concerned that her daughter has
started her period. Menarche for mom was achieved at age 11. On
exam, the girl is well appearing with no dysmorphic features or
rash. She has SMR stage 1 breast development and no pubic hair
development. Of the following, which is MOST likely going to elicit
a cause for her vaginal bleeding? A. Obtaining a bone age
radiograph B. Plotting the childs height and weight on a growth
chart C. Obtaining serum LH and FSH levels D. Obtaining a serum
estradiol concentration E. Examination of the genetalia for a
foreign body
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Genetic influence on age of menarche Typically occurs at SMR 4
breast development Vaginal bleeding at SMR 1-2 is not likely to
represent menarche or be hormonally mediated Average age of
menarche: 12.6 yrs Range: 11-14 yrs Average time of menarche after
thelarche: 2 yrs Range 0.5 5 yrs No menarche by age 16 warrants
investigation
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Physiologic leukorrhea precedes menses by 3-6 months Immature
hypothalamic-pituitary-gonadal axis at the beginning of
menstruation 50% of menstrual cycles are anovulatory in first 2
years after menarche Can cause menstrual irregularity that is
normal
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A 15 yo boy comes to the ER because of crampy abdominal pain,
diarrhea, and body aches. His siblings also have diarrhea. Exam
reveals no icterus or organomegaly, although he has increased bowel
sounds and mild diffuse abdominal tenderness. His genetalia are at
SMR4. Amount the results of his lab tests are the following: Total
bilirubin: 0.6mg/dL ALT: 18U/L Alkaline phosphatase: 460IU/L AST:
22U/L Of the following, what is the MOST likely explanation for
these lab results? A. Physiologic growth spurt B. Bone malignancy
C. Infectious hepatitis D. Inflammatory bowel disease E. Viral
gastroenteritis
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Hematocrit increases in males when the growth spurt beings
After puberty, males normal Hgb = 14-18g/dL Females remain lower:
12-15g/dL Alkaline phosphatase can increased during a growth spurt
Result of rapid bone growth (high osteoblastic activity) Can be up
to 500IU/L Cholesterol concentrations peak in early puberty Blood
pressure gradually increases Based on height, sex, age