Importantly, for the current main indication of copeptin measurement (ie, differential diagnosis of polyuria polydipsia syndrome, see below) the cut-offs for copeptin have been developed and validated with the LIA and KRYPTOR assay; the ELISA has a poor diagnostic accuracy using these cut-offs, with an especially low sensitivity in correctly diagnosing patients with central diabetes insipidus (25). This evidence concerns the gene AVP and Central diabetes insipidus.