We evaluated in 110 consecutive elderly hyponatremic @entity1 the value of traditional clinical and biochemical data and the place of a test infusion of 2 liters isotonic saline over 24 hours, in establishing the etiology of the @entity2753 . The causes of @entity2753 were as follows: 31% @entity6085 @entity1 , 23% @entity1 with @entity2753 due to diuretics, 18% potomania @entity1 , 15% @entity1702 @entity1 , 5% @entity1702 @entity6085 @entity1 , 5% @entity1 with a salt loosing syndrome and 3% @entity1 with @entity2753 of unknown origin. Several @entity1702 ( @entity1702 ) and @entity6085 @entity1 could be confounded. Usually, adults with @entity6085 show plasma @entity414 values <4 mg/dL. In our elderly population, 41% of @entity1702 @entity1 presented plasma @entity414 <4 mg/dL, while 27% of @entity6085 @entity1 showed plasma @entity414 >4 mg/dL. Eighty-two percent of @entity1702 @entity1 appeared to have plasma @entity1133 levels >30 mg/dL, but this was also the case in 21% of @entity6085 @entity1 . Twenty-nine of the @entity1702 @entity1 presented a urinary @entity1372 >30 mEq/L, but all had fractional @entity1372 excretion (FENa) lower than 0.5%. However, in @entity6085 , 42% of the @entity1 presented also FENa <0.5%. Fractional excretion of @entity1133 (FE @entity1133 ) below 50% was encountered in 82% of @entity1702 @entity1 and FE @entity1133 above 50% in only 52% of the @entity6085 @entity1 . Plasma renin and @entity1369 values were poorly discriminative. A test infusion with 2 liters isotonic saline over 24 hours allowed a correct classification of all the @entity1 . In about 2/3 of the population, administration of isotonic saline could be considered as useful ( @entity1702 , most diuretic @entity1 , potomania @entity1 , salt loosing syndrome @entity1 and some @entity1702 @entity6085 @entity1 ). A plasma @entity1372 (PNa) increase of at least 5 mEq/L 24 hours after saline infusion has been suggested as highly suggestive of @entity1702 . Nevertheless, 29% of our @entity1702 @entity1 did not increase their PNa level by 5 mEq/L or more, while 30% of our @entity6085 @entity1 did. PNa improved after 2 liters isotonic saline over 24 hours in 90 @entity1 (85%) as opposed to 12 others (9 @entity6085 and 3 diuretic @entity1 ), decreasing their plasma @entity1372 . The isotonic saline infusion test, only allows a reliable classification of @entity2753 , as far as both PNa and @entity1372 excretion were taken into account. In the @entity6085 group, 6 @entity1 (5%) presented initially manifest solute depletion and retained the 2 liters isotonic saline before developping inappropriate natriuresis. Six @entity1 showed a transient salt loosing syndrome with high fractional @entity972 excretion (FEK) and high calciuria, which differentiates them from @entity2740 @entity1 presenting also high FEK, but low calciuria. These @entity1 were also polyuric at admission. The saline infusion was well tolerated in all but 2 @entity1 , developing mild @entity891 at the end of the test infusion.

Utility and limitations of biochemical parameters in the evaluation of XXXX in the elderly.

@entity1 :: ('9606', 'Species') :: ['patients'] @entity1369 :: ('MESH:D000450', 'Chemical') :: ['aldosterone'] @entity1133 :: ('MESH:D014508', 'Chemical') :: ['urea'] @entity1372 :: ('MESH:D012964', 'Chemical') :: ['sodium'] @entity1702 :: ('MESH:D013651', 'Disease') :: ['SD', 'salt depleted'] @entity891 :: ('MESH:D001261', 'Disease') :: ['pulmonary congestion'] @entity2740 :: ('CHEBI:50264', 'Chemical') :: ['thiazide'] @entity972 :: ('MESH:D011188', 'Chemical') :: ['potassium'] @entity6085 :: ('MESH:D007177', 'Disease') :: ['SIADH'] @entity2753 :: ('MESH:D007010', 'Disease') :: ['hyponatremia'] @entity414 :: ('MESH:D014527', 'Chemical') :: ['uric acid']
@entity2753 :: (MESH:D007010,Disease) :: ['hyponatremia']
