Abstract
Purpose:: Cushing's syndrome (CS) is a rare disease having diagnostic difficulties. Many diagnostic tests have been defined but none of these are diagnostic alone. Determination of the cause is another problem which sometimes requires more sophisticated and invasive procedures. Therefore, we aimed to evaluate the utility of pretreatment plasma adrenocorticotropic hormone (ACTH)/cortisol ratios in patients with confirmed endogenous CS for the diagnosis and differential diagnosis of CS. Materials and Methods:: This retrospective evaluation included 145 patients with the diagnosis of CS, 119 patients with Cushing's disease (CD), and 26 patients with ACTH-independent CS (AICS), in a university hospital. Furthermore, 114 individuals in whom CS diagnosis was excluded with at least one negative screening test were enrolled to the study as control group. The clinical, laboratory, imaging, postsurgical pathologic records and also clinical follow-up data of all patients were evaluated. Results:: The median basal ACTH/cortisol ratio of the patients with CD was significantly higher than AICS and controls. A cutoff ACTH/cortisol ratio >2.5 was found to be diagnostic for CD with 82% specificity and 63% sensitivity. Among CD group, patients with recurrent disease had higher preoperative ACTH levels and ACTH/cortisol ratio than patients with sustained remission. Furthermore, these patients had more invasive, atypical, and larger tumors. Conclusion:: An ACTH/cortisol ratio >2.5 would be beneficial to diagnose CD together with other diagnostic tests. It is a simple test with no additional cost. Higher ratios might be related with larger, invasive, and atypical adenoma and also might be helpful to predict recurrence.
Copyright
Association for Helping Neurosurgical Sick People. This is an open access article published by Thieme under the terms of the Creative Commons Attribution-Non Derivative-Non Commercial License, permitting copying and reproduction so long as the original work is given appropriate credit.
Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/)
This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License, which permits unrestricted reproduction and distribution, for non-commercial purposes only; and use and reproduction, but not distribution, of adapted material for non-commercial purposes only, provided the original work is properly cited.