[Idiopathic hypoparathyroidsm: provocation of a tetanic seizure by the injection of a mercurial diuretic].

Idiopathic hypoparathyroidism was diagnosed in a 55-year-old patient following rather unusual circumstances: he informed the emergency ward physician attending him for congestive cardiac insufficiency consequent to coronary cardiopathy that on the two preceding occasions when such insufficiency had been relieved by the injection of a diuretic, a tetanic seizure had ensued which was corrected by intravenous administration of calcium. Treatment of the cardiac insufficiency was nonetheless instituted with the mercurial diuretic: tetany appeared a few hours later, subsiding after intravenous injection of calcium. The various possible ways in which a tetanic seizure may be triggered by a mercurial diuretic are discussed.