short stature

Question 1

Case
CC: short stature
J.O.M. 1 yo old male, sees you for the first time with the chief
complaint of short stature.

Pertinent in the birth history is history of normal birthweight and
length with note of prolonged jaundice of 1 month, with feeding
difficulties, poor cry and sluggishness.
Newborn screening: (+)
Developmental Hx: Motor: cannot sit independently; Language:
does not babble; Psychosocial: not laughing in playful situations.
Cognitive: not searching for dropped objects.
PE:
Weight for age below +2 , Height for age below -3
lethargic , sallow complexion (+) dry mottled, cool skin
coarse facial features (+) macroglossia (+) large fontanelles
(+) heart murmur
(+) umbilical hernia
(+) hypotonic extremities
Lab Results:
CBC: Hgb 80 Hct .21 PBS: MCV 120
T4 (low) TSH (high)
Thyroid scan: Lingual thyroid
Bone scan: delayed
Primary Working Impression:
Congenital Hypothyroidism
Basis:
Typical signs and Symptoms at Birth/ Hx
o Decreased activity
o Poor feeding and weight gain
o Small stature or poor growth
o Prolonged Jaundice
o Decreased stooling or constipation
o Developmental delay
o Hypotonia
o Hoarse cry
o NBS: (+) CH
Physical findings of hypothyroidism may or may not be present at
birth. Signs include the following:
o Coarse facial features
o Macroglossia
o Large fontanelles
o Umbilical hernia
o Mottled, cool, and dry skin
o Cardiac anomalies
o Pallor
o Myxedema
o Goiter
Lab Results:
Diagnosis of primary hypothyroidism is confirmed by
demonstrating decreased levels of serum thyroid hormone (total
or free T4) and elevated levels of thyroid-stimulating hormone
(TSH).
Bone aging: delayed
CBC: macrocytic anemia
Thyroid scan: ectopic lingual thyroid

Question 2

What are the differentials?

Answer 2

Differentials:

1. Cushing syndrome
   Rule in:Excessive weight gain
   Delayed bone aging
   short stature

Rule out: Stigmata of Cushing’s
syndrome: moon
facies, buffalo hump,
hypertension, purple striae and
obesity
Normal T4, TSH

2.Genetic short stature

Down Syndrome
Rule in:Short stature
Rule out:flat nasal bridge,
folded or dysplastic ears,
transverse palmar
crease, upward-slanting
palpebral fissures

Noonan syndrome
Rule in:Short stature
Rule out:triangular-shaped
face,downward-slanting
eyes, ptosis, low-set
ears with thickened helices, high nasal bridge, pectus carinatum or
excavatum

Turner syndrome (for girls only)
Rule in: Short stature
Rule out: short and stocky
build, shield-shaped chest,
webbed neck, widely
spaced nipples, high
palate, short fourth
metacarpal, low posterior hairline

Prader-Willi
syndrome
Rule in: Short stature
Rule out: Obesity
hypogonadism

Hypopituitarism
Rule in: Short stature
Delayed bone aging
Deficiency of GH may be
accompanied by
hypoadrenalism and
hypothyroidism. Prolonged
neonatal jaundice is common

Rule out:
-Growth hormone
deficiency from hypopituitarism may cause micropenis, midface
hypoplasia, and midline
defects
-Infants with congenital defects of the pituitary or
hypothalamus usually present with neonatal emergencies such as apnea, cyanosis, or severe
hypoglycemia with or without
seizures
-Microphallus in boys provides
an additional diagnostic clue

Chronic illness/malnutrition
Most chronic systemic disease can cause a child to have short
stature. Like children ] with nutritional deficiencies they will often
have greater weight loss than stature loss. Common culprits are GI,
Renal, Cardiac, Pulmonary and Immunologic disease

Question 3

Diagnostics for short stature

Answer 3

Diagnostics:
For this case: Congenital Hypothyroidism
o CBC
o free T4 and TSH
o bone age x-ray
Additional Work up for Short Stature:
o ESR
o LFTs
o urinalysis
o stool fat,
o karyotype

Question 4

Management of short stature

Answer 4

Levothyroxine given orally is the treatment of choice. -

In neonates, the recommended initial starting dose is 10–15 μg/kg
(37.5 to 50 μg/24 hr).
Levels of T4or free T4 and TSH should be monitored at
recommended intervals (approximately monthly in the first 6 mo
of life, and then every 2–3 mo between 6 mo and 2 yr) and
maintained in the normal range for age.
Children with hypothyroidism require about 4 μg/kg/24 hr, and
adults require only 2 μg/kg/24 hr.

Question 5

What is the approach to short stature?

Answer 5

Approach to Short Stature
1. Accurate measurement of length or height is essential.

2. Plot the height in age and sex appropriate WHO and CDC
   growth charts.
3. Is the height velocity impaired?
   Height velocity – rate of increase in height over a period of time.
   Height (cm) at Time 2 – Height (cm) at Time 1 x 12 = cm/yr
   Number of months between Time 1 and 2
   Where time 1 is preferably 6-12mos (at least 3-6 mos) from Time 2.
   Decreased height velocity = <5cm/year from 2 yo to puberty (12yo)
4. Is the child’s growth within the range for the family?

Question 6

Give the MPH formula

Question 7

Give the laboratories short stature

Answer 7

Laboratories:
1. Bone age – Xray of L hand and wrist
- For those with N height velocity, height percentile or SD
within midparental height
- If >2SD below the mean for age = constitutional growth
delay or pathologic condition

Question 8

Refer to specialist

Answer 8

Referral to specialist:
1. Growth velocity <5 cm (2 in) per year
2. Height-for-age curve has deviated downward across
two major height percentiles
3. Projected height more than 2 SD (10cm or 4in) below
midparental height
4. Bone age >2 SD below chronological ag
5. Children born SGA or with IUGR who do not catch up to
the growth curve by 2 years of age
6. No onset of puberty by 14 yo for boys or 13 yo for girls
7. Diagnosis of conditions approved for recombinant
growth hormone therapy

Question 9

What are common causes of short stature?

Answer 9

• Measurement - One of the most common reasons for referral to
  a pediatric endocrinology clinic is measurement error or inaccurate
  plotting.
• Endocrine – Hypothyroid, Cushing syndrome, Growth hormone
  disorders
• Systemic disease (GI, Renal, Cardiac, Pulmonary, Immunology)
• Nutritional
• Genetic syndromes

Question 10

What is constitutional growth delay?

Answer 10

Children who have normal birth size but then gradually fall on the
growth charts. Both bone and dental age is delayed. At about three years of age growth starts to parallel the growth chart curves. The patient also enters puberty at a later age than his/her peers. They
can continue to grow until their late teens and early twenties (boys
only.) Family history is often positive for delayed puberty. Adult
height is normal.

Question 11

What are the important findings in genetic short stature?

Answer 11

Children with genetic short stature also have a normal birth size.
During the first three years of life they fall on the growth chart.
They start to parallel the growth curves around three years of age.
However, they have normal bone and dental age and enter
puberty at a normal age. Final adult stature is short

Short stature – height/length >2SD below the mean for a particular
age or below 3rd percentile for age and sex according to the
population standard

Question 12

What is pathologic short stature?

Answer 12

*Height is initially within normal range that starts falling off the height curve over time
*delayed bone age
*possible causes: Prenatal onset 9maternal infections and undernutrition, chromosome defects) & postnatal onset
(nutritional deficiency, chronic systemic disease, psychosocial deprivation)

Question 13

What is constitutional growth delay?

Answer 13

*height is sustained at lower percentiles during childhood
*hallmark finding: delayed pubertal growth spurt
*Eventual normal final adult height is reached (catch up growth occurs late adolescence)
*often with history of similar growth pattern with family members
*delayed bone age (chronological age> bone age)

Question 14

What is familial short stature?

Answer 14

*stays parallel to the growth curve
*significant number of family members who are short
*bone age is not delayed (chronological age=bone age)

Question 15

Hormones Affecting Growth

Answer 15

1. Growth Hormone
2. Thyroid hormone – 1st 3 years of life
3. Glucocorticoids
4. Sex hormones
5. Insulin – important fetal growth (infant of DM mom is
   macrosomic)

Question 16

Growth Hormone deificiency

Answer 16

HYPOPITUITARISM
- Deficiency of GH with or without deficiency of other
pituitary hormones
- Short stature due to lack of stimulation of long bone
growth

Question 17

pathophysiology of GH deficiency?

Answer 17

Patho
- Damage to pituitary gland –> impaired hormone
production (GH, PRL, TSH, ACTH, LH, FSH) –> failure of
target glands and low target hormone levels (low T3,
T4, cortisol, sex hormones)

Question 18

What are the clinical manifestations of GH deficiency?

Answer 18

CM
1. Congenital – if with severe defect of GH production,
height will fall >4 SD below the mean for length by 1 yo
2. Acquired – child is N initially and CM gradually appear
and progress
- Atrophy of adrenal cortex, thyroid and gonads result in
weight loss, asthenia, sensitivity to cold, and absence
of sweating
3. Severe growth failure, tendency for hypoglycemia,
micropenis, prolonged neonatal jaundice
4. Short and broad face, prominent frontal bone,
depressed nasal bridge, saddle-shaped nose,
underdeveloped mandible, short neck, high-pitched voice, well-proportioned extremities, small hands &
feet, delayed or absent sexual maturity
5. Delayed bone age

Question 19

diagnostics

Answer 19

Dx
Dx is suspected with severe postnatal growth failure defined as
any of the ff:
- Height < 1st percentile for age and sex
- Height >2 SD below sex-adjusted mid-parental height
Height velocity is low relative to sex- and bone-aged matched
peers
1. GH levels – absent or low (<10 ug//L) in response to
stimulation or provocative test (rapid administration of
insulin, arginine, clonidine, levodopa, or glucagon)
2. TSH, T3, T4 – assess thyroid function prior to
provocative GH test as it is a pre-requisite for normal
GH synthesis
3. Cortisol, ACTH, gonadotropins, gonadal steroids –
necessary to examine other pituitary functions
4. Skeletal maturation/ bone age – delayed
5. Cranial MRI/CT – small anterior pituitary gland;
suprasellar calcification (if craniopharyngioma)

Question 20

Management of GH deficiency

Answer 20

Mgt
1. Human GH (hGH) – should be started ASAP
- Maximal response occurs in the 1st yr of tx with growth
velocity usually above the 95th percentile for age
2. Criteria for stopping tx
- Decision by the patient that he/she is tall enough
- Growth rate <1 in/yr
- Bone age >14 yrs (F) and >16 yrs (M)

Question 21

What is failure to thrive?

Answer 21

Abnormal pattern of weight gain defined by lack of
sufficient usable nutrition and documented by
inadequate weight gain over time
- Dec in velocity of weight gain leads to steady falling off
the expected weight curve on growth charts
- Weight faltering – less alarming/ negative
Etiology/Patho
- Results from inadequate usable calories necessary for
a child’s metabolic and growth demands
- Malnourished infants and young children who fail to
meet expected standards of growth
- related to environmental and psychosocial causes
- causes of insufficient growth:
o failure to ingest and utilize sufficient
calories
o malabsorption
o increased metabolic demands
- Environmental, GIT, Congenital, Infection, Metabolic,
Neurologic, Renal and Hematologic
- Symmetric FTT – (Wt, HT, HC) – long standing
malnutrition, chromosomal abnormalities, congenital
infection or teratogenic exposures
1. Organic FTT – growth failure is due to an acute or
chronic disorder that interferes with nutrient intake,
absorption, metabolism, or excretion or that increases
energy requirements

Question 22

Red flags suggesting organic causes

Answer 22

Red flags suggesting organic causes
o Cardiac findings
o Developmental delay
o Dysmorphic features
o Failure to gain weight despite adequate
caloric intake
o Organomegaly/ LNE
o Recurrent or severe pulmonary, skin, or
urinary infection
o Recurrent vomiting, diarrhea, or
dehydration

Question 23

What is non-organic FTT?

Answer 23

2. Non-organic FTT – upto 80% of children with growth
   failure do not have an apparent organic disorder;
   growth failure occurs because of environmental
   neglect (lack of food), stimulus deprivation or both

Question 24

What are the clinical manifestations of FTT?

Answer 24

CM
1. Weight that falls or remains below the 3rd percentile
for age, or decreases 2 major percentiles on the chart
2. Less than 80% median height of the child
3. BMI for age below -3
4. decreased subcutaneous fat, decreased muscle mass,
dermatitis, hepatomegaly, cheilosis or edema

Question 25

What are the diagnostics?

Answer 25

Dx
A. Anthropometric criteria
- BMI for age < 5th percentile
- Length for age < 5th percentile
- Weight deceleration crossing 2 major percentile lines
- Weight for age < 5th percentile
- Weight < 75% of median weight for age
- Weight < 75% of median weight for length
- Weight velocity <5th percentile
B. History
- Complete hx (prenatal history, nutritional, family and
travel history) and list symptoms (vomiting, diarrhea,
fever, respiratory symptoms)
- Feeding history (environment, pattern of feeding,
sources and preparation of food, feeding behavior)
- Personal medical hx (PT, surgery, medical problems)
- FHx (GI conditions, parental nutrition, parental height
at puberty, abuse)
- psychosocial assessment of the family (living
conditions, parent-child relationship, stressors, primary
caregiver)
- complete PE and dev screening, neuro exam
C. Laboratory
1. CBC, PC – consider IDA, r/o infections
2. Screen BLL
3. Urinalysis/ Urine CS
4. Serum electrolytes (renal function)
5. TSH (check for hypothyroidism)
6. Liver function tests
7. Screen for TB

Question 26

What is the management?

Answer 26

Mgt
1. Address the child’s nutritional requirements and social
issues of family, improve caregiver skills, underlying
disease
2. Nutritional management – 1.5x expected calorie and
protein intake for their age
- initiation of catch up growth may take 2 weeks

Question 27

How to calculate caloric catch up growth?

Answer 27

Formula (insert)

4-9 mos of accelerated growth must be maintained to restore a
child’s weight
Catch up height may lag behind several months

Nutrients that affect up-building:
- amino acids: lysine, taurine, tryptophan, leucine,
threonine. most impt cause of stunting. From animalderived
foods
- MCTs: from coconut and palm kernel oil (caproic,
caprylic, lauric oils). Instant source of energy. Lower
LDLs, reduce diarrhea, fat maldigestion, enhance brain
function
- Prebiotics: fructo-oligosaccharides. Enhance immunity
- Micronutrients: manage by dietary diversification, food
fortification, supplementation
3. multivitamin supplementation – for iron, zn, VitD
deficiency
4. hospitalization – severe malnutrition or failure of OPD
mgt
- indications: extreme parental impairment anxiety,
extremely poor parent-child interaction, need for
precise documentation of nutritional intake, outpatient
tx failure, psychosocial factors that put the child’s
safety at risk, serious underlying illness/medical
problem
5. developmental stimulation

Question 28

What are the complications?

Answer 28

Complications
- malnutrition infection cycle
- refeeding syndrome (ph, Ca, Mg and K) à life threatening
cardiac, pulmonary, or neurologic problems

Question 29

What is malnutrion? what are the severe forms?

Answer 29

Spectrum of conditions
- Most severe forms
o Marasmus: non-edematous severe
childhood undernutrition (SCU) with severe
wasting
o Kwashiorkor: edematous

Etiopathogenesis
1. Reductive adaptation – adaptive responses to inadequate energy/protein intake
- Mobilization of fat stores
- Once fat is depleted, protein catabolism takes place to
maintain basal metabolism
- Energy conserved by reducing activity and growth,
basal metabolism, functional reserve of organs, inflammatory and immune response
2. Changes include the following:
- Liver makes less glucose (hypoglycemia)
- Liver makes less albumin, transferrin and other
proteins
- Heat production is less (hypothermia)
- Kidneys excrete less (fluid overload)
- Heart is smaller and weaker (cardiac failure)
- Na builds up due to leaky membranes and inactive
pumps (edema)
- K leaks out of the cell
- Less gastric secretions and motility (bacterial colonization may occur in stomach and small intestines)
- Impaired immune function and RBC mass
- Micronutrient deficiencies (inc cell damage leading to
edema and hair/skin changes)

Question 30

What are the clinical manifestations?

Answer 30

CM
1. Severe wasting – most visible on thighs, buttocks,
upper arms, over the ribs and scapulae where loss of
fat and skeletal muscle is greatest
2. Failure to gain weight –> weight loss –> wasting

Question 31

Difference between Kwashiorkor and Marasmus

Question 32

Clinical signs of malnutrition

Question 33

Diagnostics for malnutrition

Answer 33

Dx
1. Dec Serum albumin – most characteristic finding
2. Hypoglycemia, low plasma amino acid, low serum
cholesterol, dec pancreatic and liver enzymes,
3. CBC – anemia
4. Bone age – delayed bone growth

Question 34

what is the management for malnutrition?

Answer 34

1. Immediate mgt of acute problems
2. Give appropriate abx for bacterial infections
   - Uncomplicated: Amoxicillin 25mkd BIDx5d
   - Complicated: Gentamicin 7.5mg OD x 7d + Ampicillin
   50mkd q6h x 2d IV/IM then Amoxicillin 25mkd q8x5d po
3. Correct dehydration, e’ abN, hypothermia, hypoglycemia
4. Correct micronutrient deficiencies
5. Cautious feeding and catch up growth
   - Refeeding syndrome: risk of feeding too quickly.
   Controlled transition over 3 days.
   o When excessive CHO are given à inc in serum insulin levels à hypoK, hypoPO4, hypoMg
   o Severe hypophosphatemia – hallmark. After
   cellular uptake of PO4 during the 1st week
   of starting to feed
   o Hypotension, dyspnea, RF, paresthesia, weakness, confusion, lethargy, sz, coma, hemolysis, thrombocytopenia
6. Co-mgt with GI specialist for caloric catch-up and nutritional support

Question 35

Stabilization phase

Answer 35

to repair cellular function, correct fluid and
electrolyte imbalance, restore homeostasis, and prevent death
from the interlinked triad of hypoglycemia, hypothermia, and
infection

Question 36

Rehabilitation Phase

Answer 36

for catch-up growth