PRECLINICAL CUSHINGS-SYNDROME WITH BODY-WEIGHT LOSS AND NORMAL CIRCADIAN-RHYTHM OF BLOOD-PRESSURE

A 68-year-old woman was referred for evaluation of an incidentally dis covered left adrenal mass, Her chief complaint was body weight loss, S he showed no symptoms or signs suggestive of Gushing's syndrome. The c ircadian rhythm of blood pressure was also normal. Hormonal assessment revealed an abnormal diurnal variation in serum cortisol levels, supp ressed baseline plasma adrenocorticotrophic hormone, and nonsuppressio n of serum and urinary cortisol with the dexamethasone suppression tes t. Adrenal scintigraphy with I-131-6-beta-iodomethyl-norcholesterol sh owed uptake on the left adrenal and inhibition of the contralateral ad renal gland. She was diagnosed as pre-clinical Gushing's syndrome. Due to the lack of clinical symptoms and the risks of surgery, we emphasi ze the importance of careful assessment of the cortisol metabolism and scintigraphic scanning under dexamethasone suppression to avoid post- surgical Addisonian crisis.