Probable Pituitary Adenoma with Adrenocorticotropin Hypersecretion (Corticotropinoma) Secondary to Addison's Disease

A 50-yr-old woman with Addison's disease from the age of 14 yr was diagnosed as empty sella turcica in 1974 (Rev Clin Esp 139: 183, 1975). She subsequently continued with hyperpigmentation in spite of adequate hormone substitution therapy which permitted her to lead a normal life. When studied she showed an extreme elevation of plasma ACTH (1500--2000 pg/ml), and with dexamethasone (2 and 8 mg/day) continued to have levels of 900 pg/ml. With 60 mg hydrocortisone daily, effects of overdosage were observed (swelling and Cushingoid facies) associated with depigmentation. However, she continued to manifest levels of plasma ACTH of 700 pg/ml and an absence of circadian rhythm. It seems likely that this patient represents a case of pituitary ACTH secretory adenoma (corticotropinoma) secondary to the preexisting Addison's disease. The circulating levels of other pituitary hormones were normal.