Could a simpler test pinpoint the cause of unquenchable thirst?

This study tested whether a mannitol infusion could be used as a simpler, more comfortable test to diagnose the cause of Polyuria-Polydipsia syndrome, a condition causing extreme thirst and excessive urination. Researchers compared how a hormone called copeptin responded to mannitol in healthy adults and in patients with two different forms of the disorder. The goal was to see if this new test could replace a more complex and uncomfortable current method.