Is Desmopressin Useful in the Evaluation of Cushing Syndrome?

The desmopressin test was first described 30 years ago. Based on the differential secretagogue properties of desmopressin on adrenocorticotropin (ACTH) release between normal and corticotroph tumor cells, this test was intended to facilitate the diagnosis of Cushing syndrome (CS). The distinct expression of the various arginine vasopressin receptors between normal pituitary, corticotroph tumors, or neuroendocrine tumors cells secreting ACTH ectopically suggested that this test could facilitate the etiological diagnosis of ACTH-dependent CS. In this review, we analyze the merits and pitfalls of desmopressin use in the diagnostic procedures of CS. Desmopressin response is not able to completely differentiate the various etiologies of CS; its wider availability has allowed its use for inferior petrosal sinus sampling confirmation of a pituitary source of ACTH excess. In addition, desmopressin can be useful to demonstrate adequate corticotroph tumor resection when its stimulatory effect is lost following pituitary surgery of patients with Cushing disease. Desmopressin response can also be a marker of the risk of longer-term postoperative recurrence. However, this review also highlights the lack of consensual criteria of normal or abnormal response to desmopressin in its various uses and requirement for further research on its usefulness.

Automated summary

The desmopressin test has been used for the diagnosis of Cushing syndrome for the past 30 years. Although it has some merits, such as confirming the source of ACTH excess and evaluating the effectiveness of tumor resection, there is a lack of consensus on the criteria for normal or abnormal response to desmopressin. Further research is needed to determine its usefulness.