Growth and Puberty Flashcards
How often should height and weight be measured and plotted
each visit which coincides with well child care due dates until age 21
Growth can be worrisome along 2 variables:
- overall height (short stature)
- growth velocity (falling off the growth curve)
*Short stature and growth failure frequently but not always occur together.
what is considered short stature
as height over 2 SD below the mean for age and gender or over 2 SD below mid-parental height.
what is considered growth failure
abnormally slow growth velocity or crossing 2 percentile lines on the growth chart
growth failure may be the first and sometimes only sign of:
an underlying health problem like
- cardiac
- GI
- renal
- endocrine abnormalities
the consequences of a delayed or missed diagnosis of growth failure may mean:
permanent height deficits as these children may have an insufficient time, even if the underlying problem is fixed, to make up lost growth potential
parameters in identifying concerning growth
- accurate measurements (if in doubt, re-measure)
- calculate mid-parental height
- possible evaluation of skeletal maturation (by bone Xray) and body proportions to determine if pt needs further w/u
how do you accurately measure height
- measure supine until age 2
- standing, no shoes, no hair ties
- have head, shoulder blades, but, and heels touch wall
- standing measurements should not be compared to previous supine measurements
why should standing measurements NOT be compared to previous supine measurements
as during the transition at 2y/o, as standing will be a little shorter
How do you calculate growth potential for boys and girls
*I remember it as the average of the biological mother and father’s heights with 1 adjustment- because girls start puberty earlier than boys and do not grow as much during puberty as boys, they lose the extra growth (equivalent to 5 inches).
Girls- subtract 5 inches from dad’s height before averaging
Boys- add 5 inches to mom’s height before averaging.
- should be w/in +/- 3 inches
- it is possible that one of the parents had an undiagnosed growth problem so their final height in the calculation may skew the child’s calculation, leaving your falsely reassured. So, ask if the parent’s height is consistent with their other biological family members.
____ is directly correlated with skeletal maturation
The time of epiphyseal closure
*If skeletal maturation (bone age) is delayed, then the patient will have more time, than their chronological age would suggest, to catch up in their height
__ can be helpful in diagnosing constitutional growth delays (CGD), but are generally reassuring in patients who have short stature due to systemic disorders that are being corrected and you are hoping to give them a better height outcome.
bone age x-ray
what is a bone age x-ray
an A/P view of the left hand and wrist. The radiologist will use the Greulich-Pyle standards to report a bone age for the patient compared against their chronological age.
How do you use bone age x-rays to assess growth?
- place a dashed line moving their current height back into the growth chart to match their skeletal age. In this particular case, doing so indicates that this patient with delayed skeletal maturation is actually on target to meet their genetic potential (mid-parental height)
- This patient will have a delayed onset of puberty with corresponding delay in epiphyseal closure, giving them extra time to meet that genetic potential.
why are bone height predictions not completely accurate in any patient
because they cannot predict the tempo of puberty.
describe a dx of familial short stature
- reflects those who are tracking fine on the growth chart headed to a mid-parental height projection of their short parents.
- Because the intrauterine environment and nutrition in pregnancy are the determinants of birth weight and initial growth, these infants will be on a higher growth percentile until age 6-18m after which they re-establish a new trajectory consistent with their genetic potential. This can be concerning until they show a normal growth velocity just along a lower growth percentile.
Because the ___ and ___ in pregnancy are the determinants of birth weight and initial growth, these infants will be on a higher growth percentile until age ____- after which they re-establish a new trajectory consistent with their genetic potential.
intrauterine environment and nutrition
6-18 months
(short stature)
how do you screen for skeletal dysplasia
An arm span significantly shorter than height is concerning. Measure the arm span fingertip to fingertip.
- In prepubertal children, the arm span should only be about 1cm less than height.
- The ratio of upper body to lower body should be 1:1 by age 10.
- At age 4y, it is 1.4:1.
- The lower body is measured pubic symphysis to the floor and upper body is total height minus the lower body measurement.
nutritional causes of short stature/abnormal growth
- zinc, iron deficiency
- anorexia
- IBD, celiac, CF
endocrine causes of short stature/abnormal growth
- hypothyroid
- GH deficiency
- Cushing
- Precocious puberty
chromosomal defect causes of short stature/abnormal growth
- Turner Syndrome
- Noonan Syndrome
- Prader-Willi Syndrome
other causes of short stature/abnormal growth
- Skeletal dysplasia
- IUGR/SGA
- Metabolic
- Chronic diseases
- Pscyhosocial deprivation
- Drugs (glucocorticoids, stimulants)
describe CGD
- A fall off in growth typically occurs with the first 2-3 years of life and following this, CGD patients will have normal growth velocity following a percentile shorter than their genetic potential.
- diagnosis of exclusion, so these kids should get a work up for “failure to thrive”
that growth charts are designed for the general population, which expects that a male will have a growth spurt around age ___, and females at ___
13-14y
11-12y
*therefore a CGD kid will appear to fall further off the curve at that age.
A history clue to CGD is
parents were “late bloomers” with maternal delay of menarche and paternal growth beyond high school.
treatment of CGD
- usually reassurance.
- An endocrinologist may consider a short course of testosterone for boys or estrogen for girls at puberty.
describe what failure to thrive is
deceleration of weight gain to less than 3% (-2SD) or crossing 2 major percentile lines in the first 3 years of life.
-Nutritional growth retardation occurs when their poor nutritional status begins to affect their linear growth with evidence of falling off the height curve.
causes of failure to thrive
1. good diet history is essential, also consider diseases which may affect: 2. metabolism or 3. GI absorption, such a 4. cardiac, 5. renal disease, 6. celiac 7. IBD among others.
-Usually these children have poor nutrition and/or 8. psychosocial factors as the cause, but don’t skip consideration of chronic diseases
After age ___, children should not fall off the height curve due to CGD or familial short stature.
3y
what height and weight pattern should alert you to underlying endocrine disorder?
note the child’s height fell off the growth curve between 6-8y but her weight % stayed the same until 8-9y
Symptoms of hypothryoidism
- delayed bone growth
- youngness appearance
- puffy face
*you may not find typical adult hypothyroidism symptoms such as weight gain, loss of hair, cold intolerance, fatigue, etc
differentiate between primary and central hypothyroidism
- Primary: failure at the level of the thyroid gland (and pit. gland keeps signaling the thyroid gland
- low T4 and high TSH
- Central hypothyroidism: occurs at the level of the pituitary gland
- low T4 and an inappropriately low or normal TSH
- often occurs concurrently with GH deficiency and other pit. hormone deficiencies
- *Work up for brain tumor
Primary hypothyroidism will respond to
exogenous levothyroxine within 4-6 weeks and the patient’s growth will improve.
The function of growth hormone is to promote:
linear growth but also to increase lean muscle mass
Causes of acquired GH deficiency
- Trauma
- CNS infection
- Tumor
- cranial irradiation
Sx of GH deficiency
- short stature
2. lack of lean muscle mass actually gives them a chubby appearance
how should you test for GH deficiency
- A random serum GH level is not helpful as GHRH generates a pulsatile release of GH, especially at night during sleep.
- However, insulin growth factor (IGF)-1 is produced from the liver in response to GH and this can be measured in serum. Additionally, the production of the binding protein for transporting IGF-1, which is known as IGFBP-3, is also controlled by GH, and is the more accurate serum level to check in infants to screen for GH deficiency.
-IGF-1 or IGFBP-3 can be done as a random draw as a screening test but are not diagnostic of growth hormone deficiency.
- Diagnosis of GHD requires a GH stimulation test, using medications such as clonidine and arginine.
- This test should be reserved for the endocrinologist.
tx of GH deficiency
exogenous GH
Hallmarks of Prader-Willi Syndrome
- short stature due to GH deficiency
- delayed puberty
- cognitive/developmental delays
- chronic hunger leading to excessive eating and obesity
Hallmarks of Noonan Syndrome
- Short stature
- possibly develoopmental delays
Facies: - wide-spaced downward slanting eyes
- low set ears
- CHD– most commonly pulmonary stenosis