A 4-year-old girl is evaluated for short stature. Height is 88 cm (below 3rd centile), mid-parental height is 162 cm (50th centile). Birth weight and length were normal. Growth velocity is 5 cm/year. Skeletal survey shows no dysplasia. IGF-1 is 35 ng/mL (low for age). Two pharmacological growth hormone stimulation tests peak at 6.2 and 7.8 ng/mL. What is the next best step?

• A MRI of the hypothalamic-pituitary region ✓
• B Reassurance and annual growth monitoring
• C Start recombinant GH therapy immediately
• D Bone marrow biopsy for storage disorder

Explanation

Two subnormal GH stimulation test peaks (<10 ng/mL) with low IGF-1 and poor growth velocity confirm growth hormone deficiency. Before starting GH replacement, MRI of the hypothalamic-pituitary region is mandatory to identify structural lesions (craniopharyngioma, pituitary hypoplasia, ectopic posterior pituitary). Reassurance is inappropriate with confirmed deficiency. Starting GH without imaging risks missing a treatable intracranial tumor. Storage disorders are unlikely with normal skeletal survey and no organomegaly.

Reference: Nelson Textbook of Pediatrics, 21st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.