Short Stature

Short Stature
see normal Height gain, Growth Hormone therapy, Indications, Tall Stature

3 Broad categories of non-endocrine short stature:

chronic disease (including undernutrition genetic disorders)
familial short stature - Genetic short stature is a common cause of short stature. Affected children usually have a height at or below the 3rd percentile, but bone age is comparable to chronologic age, and growth rate is normal.
constitutional delay of growth and development
Endocrine diseases are rare causes of short stature - Growth hormone deficiency is a relatively rare cause of short stature that should be considered if other conditions have been excluded. Affected children are often chubby, and boys may have small genitalia. Hypoglycemia may be present. It is associated with a significant delay in bone age compared with chronologic age. The diagnosis can be confirmed by inadequate release of growth hormone following stimulation with arginine or insulin.

Short stature is defined as height below the third percentile and poor growth rate is defined as growth velocity <5 cm annually. By definition, 2.5% of the population is short.

Idiopathic short stature, also known as non-growth hormone-deficient short stature, is defined by height SDS -2.25, and associated with growth rates unlikely to permit attainment of adult height in the normal range, in pediatric patients whose epiphyses are not closed and for whom diagnostic evaluation excludes other causes associated with short stature that should be observed or treated by other means. Without treatment, a boy would be < 5'4" and a girl < 4'11" as an adult.

Differential Diagnoses
History-Taking
Physical exam
Workup

Blood: CBC, Chem-14, ESR, FT4, TSH, pre-albumin, transferrin, IGF-1, IGF-BP3, Karyotype, IBD panel, Celiac disease panel
Urine: UA/micro
Sweat: Sweat Chloride
Stool: reducing substances, O&P
Imaging: bone age, (renal and cardiac ultrasounds in all patients with Turner syndrome ); Bone Age: IF delayed THEN there is “potential for growth if problem fixed”; IF normal THEN “growing at programmed rate”

Interpretation of bone age:

abnormal growth velocity = bends away from parallel
BA < CA (delayed bone age)
- normal growth velocity -- c/w constitutional delay (initially have abnormal growth velocity in the first few years of life then have normal growth velocity)
- abnormal growth velocity -- c/w chronic systemic disease, e.g. GH deficiency
BA = CA (normal bone age)
- normal growth velocity -- c/w familial short stature, SGA
- abnormal growth velocity -- c/w genetic, chromosomal, or syndrome related

Red Flags: height ?2-2.5 SD below mean, subnormal growth velocity, abnormal body proportions, abnormal height/weight ratio, dysmorphic features, goiter, abnormal CNS exam

In children younger than 3 years, track length and weight at 3-month intervals.
Standing height and weight can be tracked at 6-month intervals in older children.

Remember, Cushing syndrome causes obesity and short stature (since high glucocorticoids are a toxin).

References:
Linder B, Cassorla F. Short stature: etiology, diagnosis and treatment. JAMA. 1988;260:3171-3175
Loder RT, Estle DT, Morrison K, et al. Applicability of the Greulich and Pyle skeletal age standards to black and white children of today. Am J Dis Child. 1993;147:1329-1333
Mahoney CP. Evaluating the child with short stature. Pediatr Clin North Am. 1987;34:825-849
Rosenfield RL. Essentials of growth diagnosis. Endocrinol Metab Clin North Am. 1996;25:743-758
Vogiatzi MG, Copeland KC. The short child. Pediatr Rev. 1998;18:92-99
Kleigman.

CHLA Board Review 2005
http://www.emedicine.com/ped/topic2087.htm#targetA