In children suspected of growth hormone deficiency, what is typically used as the initial screening test?

• A. IGF-1 level
• B. GH stimulation tests
• C. MRI of the pituitary
• D. Serum cortisol

Answer: (A)

The main idea here is how we screen for suspected growth hormone deficiency in kids. IGF-1 level is used first because IGF-1 is produced in the liver in response to growth hormone and it reflects average GH activity over time, not just a momentary pulse. Since GH secretion is pulsatile, a single GH measurement isn’t reliable, but IGF-1 provides a stable clue about whether GH action is likely impaired. If IGF-1 is low for age and pubertal status, it supports testing further with GH stimulation tests to confirm deficiency. MRI of the pituitary and serum cortisol aren’t screening tests for GH deficiency; imaging is reserved for structural assessment or after a biochemical concern, and cortisol relates to adrenal function, not GH. Keep in mind that IGF-1 must be interpreted with age- and sex-specific norms and clinical context, since low IGF-1 can also occur with other conditions like undernutrition or thyroid issues.