Ekin Yiğit KÖROĞLU, Şefika Burçak POLAT, Abbas Ali TAM, Ahmet Eren SEÇEN, Fatma Dilek DELLAL KAHRAMANCA, Cevdet AYDIN, Oya TOPALOĞLU, Reyhan ERSOY, Bekir ÇAKIR
Endocrinology Research and Practice - 2026;30(2):105-111
Objective: The discontinuation of corticotropin-releasing hormone (CRH) production has shifted clinical practice toward the use of desmopressin for dynamic stimulation testing in the diagnosis of Cushing's disease (CD). However, comparative data on the responses to CRH and desmopressin remain limited. This study aimed to compare the responses of adrenocorticotropic hormone (ACTH)-secreting pituitary adenomas to desmopressin and CRH stimuli. Methods: This study included patients with histopathologically confirmed CD who underwent a CRH or desmopressin stimulation test between 2019 and 2024. After an overnight fast, baseline ACTH and cortisol levels were measured at -15 and 0 minutes. The CRH (100 mcg IV bolus) or desmopressin (10 mcg IV over 15 minutes) was administered, and blood samples were collected at 15, 30, 45, 60, 90, and 120 minutes. The primary outcomes were peak ACTH and cortisol levels, percentage increases from baseline (DeltaACTH% and DeltaCort%), and the timing of peak response. Results: A total of 30 patients (27 females and 3 males) were included; 18 underwent CRH, and 12 underwent desmopressin stimulation. The 2 groups had no significant difference in basal ACTH, basal cortisol, peak ACTH, and peak cortisol levels (P > .05). The CRH elicited a significantly greater increase in ACTH (DeltaACTH%: 340.6% +/- 271.4 vs. 159.9% +/- 105.3, P = .038) and cortisol (DeltaCort%: 77.9% +/- 50.3 vs. 43.0% +/- 26.1, P = .021) compared to desmopressin. Peak hormone responses occurred at similar time points in both tests. Conclusion: The CRH stimulates ACTH and cortisol secretion more effectively than desmopressin. Current diagnostic thresholds may not directly apply to desmopressin, potentially leading to false-negative results. Larger studies are needed to establish standardized criteria for desmopressin-based CD diagnosis.
