Syndrome of inappropriate secretion of antidiuretic hormone in traumatic brain injury: when tolvaptan becomes a life saving drug.
OBJECTIVE
To outline the role of a new drug, tolvaptan, in treating severe and chronic hyponatraemia. Tolvaptan decreases aquaporin expression in renal collecting ducts, by inhibiting antidiuretic hormone (ADH)-V2 receptors, to promote free water clearance. Given its mechanism of action, this drug seems the ideal treatment for the syndrome of inappropriate antidiuretic hormone secretion (SIADH) when the osmotic imbalance leads to life threatening complications.


METHODS
A case is described of severe hyponatraemia deriving from SIADH secondary to meningoencephalitis in a patient admitted to hospital for traumatic brain injury.


METHODS
Clinical, laboratory and radiological data at presentation and for a 1 year of follow-up were analysed.


RESULTS
Tolvaptan ameliorated hyponatraemia, brain oedema and consciousness, and drug withdrawal led to recurrence of hyponatraemia and coma.


CONCLUSIONS
In patients with SIADH, which is not self-limited, and is associated with severe cognitive impairment, the use Tolvaptan may prove life saving and should be rigorously evaluated.
Istituto Clinico Humanitas IRCCS, Via Manzoni, 56 20089 Rozzano, MI, Italy. giorgio.graziani@humanitas.it
Giorgio
G
Graziani
David
D
Cucchiari
Adriana
A
Aroldi
Claudio
C
Angelini
Paolo
P
Gaetani
Carlo
C
Selmi
D065092:Antidiuretic Hormone Receptor Antagonists; D001552:Benzazepines / Q000627:therapeutic use*; D001930:Brain Injuries / Q000150:complications / Q000188:drug therapy*; D006801:Humans; D007177:Inappropriate ADH Syndrome / Q000150:complications / Q000188:drug therapy*; D008297:Male; D008590:Meningoencephalitis / Q000150:complications / Q000188:drug therapy*; D008875:Middle Aged; D000077602:Tolvaptan
D065092:Antidiuretic Hormone Receptor Antagonists; D001552:Benzazepines; D000077602:Tolvaptan