title: Biological variation and prognosis usefulness of new biomarkers in liver transplantation.
abstract: BACKGROUND
  An observational retrospective study has been conducted, including 52 patients (37 male and 15 female), ranging from 22 to 65 years old, who underwent an orthotopic liver transplantation (OLT) at the Hospital Universitario Central de Asturias (HUCA) between 2007 and 2010.
  
  
  METHODS
  The main objective was to evaluate the post-OLT critical complication prognosis usefulness of the precursors of three new biomarkers: mid-regional proadrenomedullin (MR-proADM), carboxy-terminal-proendothelin-1 (CT-ProET-1) and mid-regional proatrial natriuretic peptide (MR-ProANP). As all of them are blood pressure mediators, stress-associated physiological phenomena are expected to affect their expression and secretion, mainly those related to blood circulation. Therefore, as a second goal, the biological variability of the biomarkers has been studied in a set of OLT patients without complications during the first postoperative week. The knowledge of the reference change value of the new biomarkers will be interesting for their correct interpretation in future investigations. The prognostic value of the new biomarkers was also compared to that of procalcitonin (PCT).
  
  
  RESULTS
  It has been shown that the basal concentration of the biomarkers is higher in patients that undergo OLT than in the normal population, correlating with the severity of the pathology. The intra-individual biological variation of these biomarkers is similar to other biochemical parameters, the reference change value for OLT patients being 90% for CT-proET-1, 112% for MR-proADM and 127% for MR-proANP.
  
  
  CONCLUSIONS
  Multivariate analysis showed that MR-proADM was the best biomarker for the prognosis of severe complications.
authors.affiliation: Clinical Biochemistry Laboratory , AGC Laboratory of Medicine, Hospital Universitario Central de Asturias, Oviedo, Spain.
authors.forename: Diego
authors.initials: D
authors.lastname: Miguel
authors.forename: Belén
authors.initials: B
authors.lastname: Prieto
authors.forename: Francisco V
authors.initials: FV
authors.lastname: Álvarez
mesh_terms: D053607:Adrenomedullin / Q000097:blood*; D000328:Adult; D000368:Aged; D009320:Atrial Natriuretic Factor / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D019332:Endothelin-1 / Q000097:blood*; D005260:Female; D006801:Humans; D016031:Liver Transplantation / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010446:Peptide Fragments / Q000097:blood*; D011379:Prognosis; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D015415:Biomarkers; C557077:C-terminal proendothelin-1; D019332:Endothelin-1; D010446:Peptide Fragments; D053607:Adrenomedullin; D009320:Atrial Natriuretic Factor