====== Endocrine screening ======

8 A.M. [[cortisol]] & 24-hour urine free cortisol

● cortisol ↑ in [[hypercortisolism]] ([[Cushing syndrome]]) 

● cortisol ↓ in [[hypoadrenalism]] (primary or secondary)
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Free [[T4]], [[TSH]]

[[Hypothyroidism]]

● T4 ↓ & TSH ↑ in [[primary hypothyroidism]] (this may cause [[thyrotroph hyperplasia]] in pituitary gland)

● T4 ↓ & TSH nl or ↓ in [[secondary hypothyroidism]] (as in [[hypopituitarism]])
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[[Prolactin]]

● ↑ or ↑↑ with [[prolactinoma]]

● slight ↑ with [[pituitary stalk effect]] (usually < 90 ng/ml)
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[[Gonadotropin]]s ([[FSH]], [[LH]]) and sex steroids (♀: [[estradiol]], ♂: [[testosterone]])

● ↓ in hypogonadotrophic hypogonadism (from [[mass effect]] causing compression of the [[pituitary gland]])

● ↑ with [[gonadotropin-secreting adenoma]]
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[[Insulin-like growth factor 1]] (IGF- 1) AKA [[somatomedin C]]

● ↑ in [[acromegaly]]

● ↓ in [[hypopituitarism]] (one of the most sensitive markers)

IGF-1 is the primary test for excess [[growth hormone]] (GH); direct measurement of GH is unreliable