Copeptin, Serum/Plasma

Copeptin

pmol/L

Interpretive guidelines effective 16-Oct-2023:
Adult (≥ 18 years):

Reference Interval (Non-Stimulated, Non-Fasting): < 13.1pmol/L (Keller T et al., JACC 2010; 55(19):2096-2106)

Nephrogenic Diabetes Insipidus (DI):

Baseline copeptin ≥21.4 pmol/L in adults with polyuria-polydipsia syndrome had 100% sensitivity (sens) and specificity (spec) (Timper K et al., JCEM 2015; 100(6):2268-2274)

Central DI:

• Following hypertonic saline infusion, copeptin ≤ 4.9 pmol/L identified complete/partial central DI (vs. primary polydipsia (PP)) with 93% sens and 100% spec (Fenske W et al., NEJM 2018; 379:428-439)
• At 60 min following arginine stimulation, copeptin ≤3.8 pmol/L identified complete/partial central DI (vs. PP) with 93% sens and 92% spec (Winzeler B et al., Lancet 2019; 394(10198):587-595)

Pediatric (< 18 years):

Reference Intervals (Non-Stimulated, Non-Fasting): <14.5 pmol/L (Du J-M et al., Peptides 2013; 45:61-65)

Copeptin may be elevated at birth (< 3 days) with perinatal stress (Burckhardt M-A et al., JCEM 2014; 99(9):E1750-E1753)

Baseline Copeptin in Children with Polyuria-Polydipsia Syndrome:

Nephrogenic DI: > 20 pmol/L

Central DI: ≤ 3.5 pmol/L had 100% sens and 87% spec (so central DI excluded at > 3.5 pmol/L); ≤ 1.1 pmol/L had 29% sens and 100% spec (so PP excluded)(Bonnet L et al., ClinEndo 2022; 96:47-53)

Stimulated Copeptin in Children (e.g. Arginine, Water Deprivation, or Hypernatremia):

Complete Central DI: ≤ 3.5 pmol/L

Partial or Complete Central DI: ≤4.9 pmol/L

Sens 88-100%, spec 66-80% (Binder G et al., ClinEndo 2023; 98:548-553; Tuli G et al., ClinEndo 2018; 88:873-879; Al Nofal A et al., JPEM 2023; 36(5):492-499)