2007 PREP SA on CD-ROM
Question: 202
You are evaluating a short 14-year-old boy who is underweight for height. His growth curve is
shown in Item Q202A. He says he is feeling well. His mother worries that he does not have as
much stamina as he did at age 12 years.
Of the following, the laboratory study that is MOST likely to be useful in assessing the reason for
poor growth is measurement of
A. free thyroxine
B. insulin-like growth factor 1
C. insulin-like growth factor binding protein 3
D. tissue transglutaminase antibody
E. urine free cortisol
Copyright © 2007 by the American Academy of Pediatrics
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2007 PREP SA on CD-ROM
Question: 202
Item Q202A: Growth curve for the boy described in the vignette.
Copyright © 2007 by the American Academy of Pediatrics
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2007 PREP SA on CD-ROM
Critique: 202
Preferred Response: D
Most children who have short stature and slow growth, such as the boy described in the
vignette, do not have endocrine disorders. Healthy children may have a slow linear growth
velocity during middle childhood and early adolescent ages if they have constitutional growth
delay. However, severe attenuation of weight gain preceding attenuation of linear growth almost
always is a sign of a severe underlying disorder.
The most common pathologic causes of slow growth are an underlying metabolic, renal, or
gastrointestinal disorder. Laboratory tests directed at identifying these disorders can help
distinguish between constitutional delay and other conditions. Celiac disease is a common cause
of short stature associated with underweight. If immunoglobulin A concentrations are normal,
measurement of tissue transglutaminase antibody is the best screening study for celiac disease.
Endocrine causes of growth attenuation, including hypothyroidism, growth hormone deficiency,
and Cushing syndrome, are not associated with decreased weight for height. Measures of
insulin-like growth factor-1 (IGF-1) and insulin-like growth factor binding protein 3 are good
screening studies for growth hormone deficiency, although hepatic IGF-1 production also is
stimulated by insulin and may be low in underweight children. A 24-hour urine free cortisol
measurement is an excellent screening study for Cushing syndrome, but this disorder is
associated with at least mild obesity.
References:
Kemp S, Güngör N. Growth failure. eMedicine Specialties: Pediatrics: Endocrinology. 2005.
Available at: http://www.emedicine.com/ped/topic902.htm
Reiter EO. Short stature/tall stature. In: Burg FD, Ingelfinger JR, Polin RA, Gershon AA, eds.
Gellis & Kagan’s Current Pediatric Therapy. Philadelphia, Pa: WB Saunders; 2003:679-682
Israel EJ, Levitsky LL, Anupindi SA, Pitman MB. Case Records of the Massachusetts General
Hospital. Weekly clinicopathological exercises. Case 3-2005. A 14-year-old boy with recent
slowing of growth and delayed puberty. N Engl J Med. 2005;352:393-403
van Rijn JC, Grote FK, Oostdijk W, Wit JM. Short stature and the probability of coeliac disease,
in the absence of gastrointestinal symptoms. Arch Dis Child. 2004;89:882-883. Available at:
http://adc.bmjjournals.com/cgi/content/full/89/9/882
Copyright © 2007 by the American Academy of Pediatrics
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