Lab Abnormalities in Hypopituitarism
Gonadotropins (FSH and LH)
Thyroid-stimulating hormone (TSH)
Low FSH and LH, decreased estradiol, and decreased testosterone. The GnRH stimulation test distinguishes an anterior pituitary from a hypothalamic disorder (no gonadotropin response in the former and eventual response in the latter).
Decreased GH and somatomedin C (insulin-like growth factor, which is synthesized in the liver and stimulated by GH), hypoglycemia (50%; GH is a gluconeogenic hormone). Stimulation tests are abnormal.
Low T4, low resin T3 uptake, low free T4 index, low TSH, increased CK (myopathy), increased LDL (decreased synthesis of LDL receptors),