Pseudonyms
ADH, Vasopressin, CT proAVP, C-Terminus Pro-Arginine Vasopressin
Collection Requirements
Morning samples after 8 hour fast (without water restriction) are recommended unless otherwise stated by clinician.
Tube Colour
Pink
Test image(s)
Requires own tube?
No
Department
BiochemistryReference Interval
A random copeptin of ≥ 21.4 pmol/L is consistent wtih nephrogenic diabetes insipidus.
In a hypertonic saline infusion test, once plasma sodium is ≥ 147 mmol/L, a copeptin of > 4.9 pmol/L suggests primary polydipsia and a copeptin of ≤ 4.9 pmol/L is consistent with central diabetes insipidus.
Reference: Christ-Crain et al, J Clin Endocrinol Metab 2022; 1727-1738.
Availability
Fortnightly
Reference Laboratory
Northern Pathology Victoria. Specimen Reception, Northern Hospital. 185 Cooper St Epping Vic 3076 (P) 03 84058351
Fee
AUD $50 not Medicare rebatable
Notes
Copeptin (aka C- Terminus Pro-Arginine Vasopressin, CT-proAVP) is the C-terminal glycoprotein moiety of pre-provasopressin and is released in the same amount as AVP and can be used as a surrogate for ADH concentration. Copeptin has a much longer plasma half-life than ADH (days compared to minutes) and has greater stability at room temperature and therefore is less prone to preanalytical errors.
Test code: COPEP
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