Adrenocorticotrophin-Dependent Hypercortisolism: Imaging versus Laboratory Diagnosis

作者：Tancic Gajic Milina^*; Vujovic Svetlana; Ivovic Miomira; Stojanovic Milos; Marina Ljiljana; Barac Marija; Micic Dragan

来源：Srpski Arhiv za Celokupno Lekarstvo, 2012, 140(7-8): 500-504.

DOI：10.2298/SARH1208500T

• adrenocorticotrophin
• Cushing's syndrome
• pituitary gland anterior
• sampling
• inferior petrosal sinus

Introduction Cushing's syndrome results from inappropriate exposure to excessive glucocorticoids. Untreated, it has significant morbidity and mortality.
Case Outline A 38-year-old woman with a typical appearance of Cushing's syndrome was admitted for further evaluation of hypercortisolism. The serum cortisol level was elevated without diurnal rhythm, without adequate suppression of cortisol after 1 mg dexamethasone suppression test. 24-hour urinary-free cortisol level was elevated. Differential diagnostic testing indicated adrenocorticotrophin (ACTH)dependent lesion of the pituitary origin. Pituitary abnormalities were not observed during repeated MRI scanning. Inferior petrosal sinus sampling (IPSS) was performed: 1) Baseline ratio ACTH inferior petrosal sinus/peripheral was <2; 2) Corticotropin-releasing hormone (CRH) stimulated ratio ACTH inferior petrosal sinus/peripheral was <3; 3) Baseline intersinus ratio of ACTH was <1.4; 4) Increase in inferior petrosal sinus and peripheral ACTH of more than 50 percent above basal level after CRH; 5) Baseline ratio ACTH vena jugularis interna/peripheral was >1.7. Transsphenoidal exploration and removal of the pituitary tumor was performed inducing iatrogenic hypopituitarism. Postoperative morning serum cortisol level was less than 50 nmol/l on adequate replacement therapy with hydrocortisone, levothyroxine and estro-progestagen.
Conclusion No single test provides absolute distinction, but the combined results of several tests generally provide a correct diagnosis of Cushing's syndrome.

• 出版日期2012-8