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]