The use of copeptin, the stable peptide of the vasopressin precursor, in the differential diagnosis of sodium imbalance in patients with acute diseases

Abstract

Although limited by small sample size, this study found that plasma copeptin level appears to add very little information to the work up of sodium imbalance in this cohort of medical inpatients. It is likely that the non-osmotic "stress"-stimulus in acute hospitalised patients is a major confounder and overrules the osmotic stimulus.

Kidney Function and Plasma Copeptin Levels in Healthy Kidney Donors and Autosomal Dominant Polycystic Kidney Disease Patients

“…These data indicate that GFR, as such, is not a determinant of copeptin levels. In the literature, the association between kidney function and plasma copeptin has been described in several studies, with higher copeptin concentrations when kidney function is lower (15)(16)(17)(18). In our opinion, two mechanisms can underlie the negative association in these studies.…”

“…Copeptin has a molecular mass of only 5 kD, which makes it subject to kidney clearance. Indeed, several studies showed inverse associations between kidney function and copeptin (15)(16)(17)(18).…”

Diabetes Insipidus: A Review

“…ADH assay, while helpful to differentiate between the two, is often inaccurate due to ADH's instability in the blood. Radioimmunoassays which detect copeptin, a stable molecule secreted with ADH may be helpful in quantification of serum ADH levels [113,115].…”

Copeptin: Pathophysiology and potential clinical impact

“…SIADH) from hypovolemic hyponatremia [76]. It is also worth mentioning that higher copeptin concentration is observed in patients with hyponatremia in course of chronic renal failure compared to patients with gastrointestinal loss [77].…”