Cortisol, the major adrenal glucocorticoid steroid hormone, is usually under feedback control by pituitary ACTH and the hypothalamus. Causes of low cortisol include pituitary failure or destruction, with resultant loss of ACTH to stimulate the adrenal, and metabolic errors or destruction of the adrenal gland itself (adrenogenital syndromes, tuberculosis, histoplasmosis). The diagnosis of hypoadrenalism usually requires confirmation with ACTH stimulation, due to the circadian rhythms of cortisol and other factors. Causes of increased cortisol, which may initially present as simply a loss of normal diurnal variation, include pituitary overproduction of ACTH, production of ACTH by a tumor (notably oat cell cancers), and adrenal adenomas.
LC Sample ReportQD Sample ReportTest Code(s):
004051, 367
Preparation:No fasting required. Stop biotin consumption at least 72 hours prior to the collection.
Test Results:
1-2 days. May take longer based on weather, holiday or lab delays.
