title: Hyponatremia and brain injury: absence of alterations of serum brain natriuretic peptide and vasopressin.
abstract: OBJECTIVE
  To study any possible relation between hyponatremia following brain injury and the presence of cerebral salt-wasting syndrome (CSWS) or the syndrome of inappropriate secretion of antidiuretic hormone (SIADH), and if vasopressin, brain natriuretic peptide (BNP) and aldosterone have a role in its mechanism.
  
  
  METHODS
  Patients with brain injury admitted to the intensive care unit were included and had their BNP, aldosterone and vasopressin levels dosed on day 7.
  
  
  RESULTS
  Twenty six adult patients were included in the study. Nine (34.6%) had hyponatremia and presented with a negative water balance and higher values of urinary sodium, serum potassium and diuresis than patients with normonatremia. The serum levels of BNP, aldosterone, and vasopressin were normal and no relation was observed between plasma sodium and BNP, aldosterone or vasopressin.
  
  
  CONCLUSIONS
  The most likely cause of hyponatremia was CSWS and there was no correlation between BNP, aldosterone and vasopressin with serum sodium level.
authors.affiliation: Intensive Care Unit, Hospital de Base do Distrito Federal, Brasília, DF, Brazil. knc@terra.com.br
authors.forename: Karina Nascimento
authors.initials: KN
authors.lastname: Costa
authors.forename: Helen Mayumi
authors.initials: HM
authors.lastname: Nakamura
authors.forename: Leonardo Rodrigues da
authors.initials: LR
authors.lastname: Cruz
authors.forename: Lucas Sampaio Valente Fernandes de
authors.initials: LS
authors.lastname: Miranda
authors.forename: Rubens Carneiro dos
authors.initials: RC
authors.lastname: Santos-Neto
authors.forename: Susyanne de Lavor
authors.initials: Sde L
authors.lastname: Cosme
authors.forename: Luiz Augusto
authors.initials: LA
authors.lastname: Casulari
mesh_terms: D000293:Adolescent; D000328:Adult; D000450:Aldosterone / Q000097:blood*; D001928:Brain Diseases, Metabolic / Q000097:blood / Q000150:complications / Q000175:diagnosis; D001930:Brain Injuries / Q000097:blood* / Q000150:complications; D005260:Female; D006801:Humans; D007010:Hyponatremia / Q000097:blood* / Q000175:diagnosis / Q000209:etiology; D007177:Inappropriate ADH Syndrome / Q000097:blood / Q000150:complications / Q000175:diagnosis; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D014667:Vasopressins / Q000097:blood*; D055815:Young Adult
chemical_list: D014667:Vasopressins; D020097:Natriuretic Peptide, Brain; D000450:Aldosterone