Copeptin Measurement After Mannitol and Hypertonic Saline for the Diagnosis of Polyuria-polydipsia Syndrome

The aim of this study is to evaluate whether a new test using mannitol infusion can diagnose the cause of polyuria-polydipsia syndrome as accurately as the current standard test (hypertonic saline infusion) and to compare which test patients prefer. The goal is to identify a simpler and more patient-friendly diagnostic approach.

NCT Number	NCT07569861
Lead Sponsor	University Hospital, Basel, Switzerland
Conditions	Arginine Vasopressin Deficiency, Primary Polydipsia
Enrollment	144 participants
Start Date	2026-06-16
Primary Completion	2030-06 (estimated)
Study Completion	2030-06 (estimated)
Updated on ClinicalTrials.gov	2026-06-18