[Hypo-uricemia in the syndrome of inappropriate secretion of antidiuretic hormone: A prospective study].
OBJECTIVE
Hypo-uricemia is still considered as a hallmark of the syndrome of inappropriate secretion of antidiuretic hormone.


METHODS
We analyzed prospectively 98 hospitalized patients with hyponatremia (≤135 mmol/L), excluding those receiving diuretic treatment. Gold standard for the syndrome of inappropriate secretion of antidiuretic hormone combined plasma hypoosmolality, inappropriately concentrated urine, and normal volemia.


RESULTS
A final diagnosis of inappropriate secretion of antidiuretic hormone was obtained in 55 patients. They were significantly hypo-uricemic (188 μmol/L [153-245], median [interquartile range]) versus 241 μmol/L, [179-333]; p<0,02) but hypo-uricemia (≤240 μmol/L) performed poorly as a diagnostic test: 71 % sensitivity, 53 % specificity. Positive and negative likelihood ratios were 1,67 and 0,49, respectively.


CONCLUSIONS
The syndrome of inappropriate secretion of antidiuretic hormone is associated with a lower plasma uric acid concentration, but in routine clinical practice, contrary to what has been previously published, this difference is insufficient for hypouricemia to discriminate reliably between the syndrome of inappropriate secretion of antidiuretic hormone and other causes of hyponatremia.
Passeron
A
A
Service de médecine interne, hôpital européen Georges-Pompidou, Assistance publique-Hôpitaux de Paris, faculté de médecine Paris Descartes, 75098 Paris cedex 15, France. amelie.passeron@egp.aphp.fr
Blanchard
A
A
Capron
L
L
D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D007177:Inappropriate ADH Syndrome / Q000150:complications* / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D015499:Renal Tubular Transport, Inborn Errors / Q000209:etiology; D012680:Sensitivity and Specificity; D014545:Urinary Calculi / Q000209:etiology