DISCUSSION
Hyponatremia is the direct consequence of inappropriate ADH secretion.
Depending on its depth, the clinical picture may range from asymptomatic
patient to coma or cardiorespiratory arrest, via neurological disorders
such as convulsions, stupor, agitation and confusion if it is acute, or
apathy, anorexia, muscle cramps and memory and balance disorders when it
is progressive. The clinical picture thus depends mainly on the speed of
onset and depth of hyponatremia [1].
ISADH combines several symptoms first described by Schwartz and
Bartter in 1967, resulting in normovolemic hyponatremia [2].
However, it remains a diagnosis of elimination in the presence of
hyponatremia. The diagnostic criteria are presented in Table 1 [1].
Table 1 : diagnostic criteria for SIADH [1]