Among the convulsive disorders there is one, tetany, in which certain of the elements in the etiology are known. Tetany occurs in persons in whom there is loss or decreased function of the parathyroid glands, or it may arise in normal persons following prolonged hyperpnea. It is accompanied by a decrease in the ionized calcium and by an increase in the alkalinity of body fluids.
The question at once arises whether tetany and other convulsive disorders have features in common, and, if so, whether this holds therapeutic implications for patients commonly classed as epileptic. In pursuing this inquiry one wishes to know how commonly tetany and epilepsy are associated, whether distinctive symptoms or signs that are latent in one can be elicited in the other, whether measures that are effective in either preventing or producing tetany are of any influence in epilepsy, and whether laboratory examinations of epileptic patients reveal
LENNOX WG, ALLEN MB. STUDIES IN EPILEPSYXI. THE CALCIUM CONTENT OF THE BLOOD AND OF THE SPINAL FLUID. Arch NeurPsych. 1930;24(6):1199-1205. doi:10.1001/archneurpsyc.1930.02220180096007