SHORT STATURE
DEFINITION:
Children whose height is equal to or greater than 3 standard
deviations (SD) below the mean height for age.
EPIDEMIOLOGY:
- incidence: ?
- risk factors:
- see differential diagnosis
DIFFERENTIAL DIAGNOSIS:
BACKGROUND:
- 23-28 cm/year (9-11 inches/year)
- first growth spurt
- growth rate is independent of endogenous growth hormone (GH)
- represents most rapid growth rate but is highly variable
- SGA may grow at a higher rate than normal
- LGA may grow at a lower rate than normal
- crossing of channels may be physiologic
2. 1 -> 3 Years
- 7.5-13 cm/year (3-5 inches/year)
- represents a slowing down of the growth rate
3. 3 Years -> Puberty
- 5-6 cm/year (2-2.5 inches/year)
- represents a steady rate of growth
4. Adolescence (12-15 years)
- up to 9-10 cm/year
- second growth spurt
- growth rate dependent upon an increased production of
adrenal and gonadal hormones
- M: growth spurt occurs after 1st signs of pubertal onset
- F: growth spurt occurs before 1st signs of pubertal onset
2. Midparental Target Height:
- (fathers height + [mothers height + 13 cm])/2
2. Females:
- (mothers height + [fathers height - 13 cm])/2
CLINICAL FEATURES:
- must plot out growth over time to ascertain the shape of the
growth curve
- significant channeling down
- slow but consistent falling off of growth curve
- height >3 SD below the average height for age
2. Physical
- gross proportional abnormalities (skeletal dysplasias)
- dysmorphic features (chromosomal disorders)
- pubertal status
- hypothyroidism (dry course hair & skin, slow hair/nail
growth)
- Cushinoid (hypertension, increased weight, acne, thin skin,
hirsutism)
- Growth Hormone deficient (hair and nails)
INVESTIGATIONS:
- if <2 years of age - supine
- if >2 years of age - standing
2. Growth Charts
- normal: 0->36 months; 3->18 years
- others: Trisomy 21 and Turners growth charts
2. First Line Investigations
- CBC - anemia (bone marrow suppression, malabsorption)
- LFT - AST, ALT, alkaline phosphatase (liver abnormalities)
- TFT - TSH, T4, T3 (hypothyroidism)
- RFT - electrolytes, BUN, creatinine
- amylase
2. Imaging Studies
- radiographic determination of the degree of epiphyseal
fusion
- an index of somatic maturation
- a measure of growth potential
2. Skull X-Rays
- gross abnormalities, i.e., space-occupying lesion
- calcifications in the suprsellar region
3. Second Line Investigations
- to rule out genetic/chromosomal defects
2. Malabsorption Screen
- CBC, RBC folate & carotene, antigliadin antibody
3. Imaging Studies
- intracranial pathology
- pituitary or hypothalamic abnormalities
4. Hormone Abnormalities
- 24 hour urinary cortisol >250 ug/day
2. Growth Hormone Deficiency (GH)
- normal ICF-1 rules out GH deficiency
- GH stimulation tests (provocative stimuli):
- physiologic - basal, exercise
- pharmacologic - arginine +/- insulin, clonidine + L-Dopa,
glucagon, L-Dopa + pro-pranolol
- abnormal if no rise in growth hormone level after the
axis has been stimulated physiologically or
pharmacologically
MANAGEMENT:
- nutrition for malnutrition
- malabsorption
- congenital heart disease
- hypothyroidism
2. Reassurance
- familial short stature
- constitutional short stature
3. Constitutional Short Stature
4. Growth Hormone Defeciency
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