title: Cerebral salt wasting: truths, fallacies, theories, and challenges.
abstract: BACKGROUND
  The reported prevalence of cerebral salt wasting has increased in the past three decades. A cerebral lesion and a large natriuresis without a known stimulus to excrete so much sodium (Na ) constitute its essential two elements.
  
  
  OBJECTIVE
  To review the topic of cerebral salt wasting. There is a diagnostic problem because it is difficult to confirm that a stimulus for the renal excretion of Na is absent.
  
  
  METHODS
  Review article.
  
  
  METHODS
  None.
  
  
  RESULTS
  Three fallacies concerning cerebral salt wasting are stressed: first, cerebral salt wasting is a common disorder; second, hyponatremia should be one of its diagnostic features; and third, most patients have a negative balance for Na when the diagnosis of cerebral salt wasting is made. Three causes for the large natriuresis were considered: first, a severe degree of extracellular fluid volume expansion could down-regulate transporters involved in renal Na resorption; second, an adrenergic surge could cause a pressure natriuresis; and third, natriuretic agents might become more potent when the effective extracellular fluid volume is high.
  
  
  CONCLUSIONS
  Cerebral salt wasting is probably much less common than the literature suggests. With optimal treatment in the intensive care unit, hyponatremia should not develop.
authors.affiliation: Department of Pediatric Neurosurgery, Hospital for Sick Children, Toronto, Canada.
authors.forename: Sheila
authors.initials: S
authors.lastname: Singh
authors.forename: Desmond
authors.initials: D
authors.lastname: Bohn
authors.forename: Ana P C P
authors.initials: AP
authors.lastname: Carlotti
authors.forename: Michael
authors.initials: M
authors.lastname: Cusimano
authors.forename: James T
authors.initials: JT
authors.lastname: Rutka
authors.forename: Mitchell L
authors.initials: ML
authors.lastname: Halperin
mesh_terms: D001927:Brain Diseases / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology; D006801:Humans; D007010:Hyponatremia / Q000503:physiopathology; D007177:Inappropriate ADH Syndrome / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology