title: CT-pro-AVP as a tool for assessment of intravascular volume depletion in severe hyponatremia.
abstract: BACKGROUND
  Assessment of volume status is essential to best manage hyponatremic patients but is not always accurate in clinical practice. The aim of this study was to evaluate the reliability of C-terminal portion of pro-arginine-vasopressin (CT-pro-AVP), a surrogate biomarker of vasopressin release, in assessing intravascular volume (IVV) depletion in hypoosmolar hyponatremic patients.
  
  
  METHODS
  Plasma CT-pro-AVP and urea-to-creatinine ratio (Ur/Cr) were performed in 131 hospitalized patients presenting chronic severe hypoosmolar hyponatremia. At hospital discharge, their IVV was evaluated regardless of CT-pro-AVP concentrations. All patients were then classified as decreased or as normal/expanded IVV group.
  
  
  RESULTS
  Plasma CT-pro-AVP levels were higher in patients with decreased IVV (34.6 vs. 11.3 pmol/L, p<0.001) and exhibited a reliable performance for assessment of decreased IVV (ROC AUC at 0.717 [95% CI 0.629-0.805]). The combination of CT-pro-AVP and Ur/Cr resulted in an improved ROC AUC up to 0.787 (95% CI 0.709-0.866).
  
  
  CONCLUSIONS
  Our findings support the hypothesis that CT-pro-AVP plasma level may reflect IVV and would be a tool for its assessment. This performance has been magnified by its combination with Ur/Cr. A dual-marker strategy may help clinicians to optimize the management of severe hyponatremia especially in case of confusing clinical presentations.
authors.affiliation: Department of Biochemistry and Hormonology, CHU Montpellier, Montpellier, 34295, France; UMR CNRS 9214 - Inserm U1046, Physiologie et Médecine Expérimentale du cœur et des muscles - PHYMEDEXP, Université de Montpellier, Montpellier, France.
authors.forename: Guilaine
authors.initials: G
authors.lastname: Boursier
authors.affiliation: Department of Biochemistry and Hormonology, CHU Montpellier, Montpellier, 34295, France.
authors.forename: Marion
authors.initials: M
authors.lastname: Alméras
authors.affiliation: Department of Biochemistry and Hormonology, CHU Montpellier, Montpellier, 34295, France.
authors.forename: Delphine
authors.initials: D
authors.lastname: Buthiau
authors.affiliation: Department of Internal Medicine, CHU Montpellier, Montpellier, 34295, France.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Jugant
authors.affiliation: Department of Intensive Care Medicine, CHU Montpellier, Montpellier, 34295, France.
authors.forename: Delphine
authors.initials: D
authors.lastname: Daubin
authors.affiliation: Department of Biochemistry and Hormonology, CHU Montpellier, Montpellier, 34295, France; UMR CNRS 9214 - Inserm U1046, Physiologie et Médecine Expérimentale du cœur et des muscles - PHYMEDEXP, Université de Montpellier, Montpellier, France.
authors.forename: Nils
authors.initials: N
authors.lastname: Kuster
authors.affiliation: Department of Biochemistry and Hormonology, CHU Montpellier, Montpellier, 34295, France.
authors.forename: Anne-Marie
authors.initials: AM
authors.lastname: Dupuy
authors.affiliation: Department of Internal Medicine, CHU Montpellier, Montpellier, 34295, France.
authors.forename: Jean
authors.initials: J
authors.lastname: Ribstein
authors.affiliation: UMR CNRS 9214 - Inserm U1046, Physiologie et Médecine Expérimentale du cœur et des muscles - PHYMEDEXP, Université de Montpellier, Montpellier, France; Department of Intensive Care Medicine, CHU Montpellier, Montpellier, 34295, France.
authors.forename: Kada
authors.initials: K
authors.lastname: Klouche
authors.affiliation: Department of Biochemistry and Hormonology, CHU Montpellier, Montpellier, 34295, France; UMR CNRS 9214 - Inserm U1046, Physiologie et Médecine Expérimentale du cœur et des muscles - PHYMEDEXP, Université de Montpellier, Montpellier, France. Electronic address: jp-cristol@chu-montpellier.fr.
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Cristol
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001127:Arginine Vasopressin / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D001810:Blood Volume / Q000502:physiology*; D005260:Female; D006801:Humans; D007010:Hyponatremia / Q000097:blood* / Q000175:diagnosis* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D012720:Severity of Illness Index
chemical_list: D015415:Biomarkers; D001127:Arginine Vasopressin
keywords: CT-pro-AVP; Hyponatremia; Hypovolemia; Intravascular volume